Method and device for analysing antimicrobial compound susceptibility of pathogenic microorganisms in body fluid samples

Abstract

The invention relates to a method and device for analysing antimicrobial compound susceptibility of pathogenic microorganisms in body fluid samples. The method includes the steps of providing at least one body fluid sample, filtering the at least one body fluid sample through at least one catch filter which is configured for capturing at least a fraction of pathogenic microorganisms from the at least one body fluid sample if present in the body fluid sample, applying at least one antimicrobial compound to at least part of the at least one catch filter, in particular to the fraction of pathogenic microorganisms, such that at least a fraction of the captured pathogenic microorganisms extracellularly secrete antimicrobial responsive biomolecules, analysing the extracellularly secreted antimicrobial responsive biomolecules and determining at least one susceptibility characteristic thereof, and comparing at least one determined susceptibility characteristic with at least one reference characteristic corresponding to the at least one determined susceptibility characteristic thereby determining the susceptibility of at least part of the captured pathogenic microorganisms to the at least one antimicrobial compound.

Description

[0001] Method and device for analysing antimicrobial compound susceptibility of pathogenic microorganisms in body fluid samples

[0002] The invention relates to a method for analysing antimicrobial compound susceptibility of pathogenic microorganisms in body fluid samples. The invention also relates to a device for processing at least one body fluid sample for analysing antimicrobial compound susceptibility of pathogenic microorganisms in the at least one body fluid sample.

[0003] Infectious diseases can be prevented and treated with correct antimicrobial medicaments, such as antibiotics, antifungals, and antiparasitic. However, bacteria, fungi and parasites can become resistant for antimicrobial drugs making the drugs ineffective. This results in infections which are difficult or impossible to treat which increase the risk of spreading diseases globally. It is known that antimicrobial resistance (AMR) is accelerated by human activity, in particular by misuse and overuse of antimicrobial medicaments. Hence, reducing, preferably circumventing, misuse and overuse of antimicrobial medicaments is of great importance. This can be done by diagnostic testing to show whether or not an antimicrobial medicament is actually needed and which type is to be applied.

[0004] Current diagnostic tests usually make use of laboratory testing of body fluid samples. These tests typically require culture steps of pathogens, like bacteria and fungi, of at least 10 hours to collect a sufficient concentration of pathogens for further analysis. An entire diagnostic test often requires 24 to 72 hours or more to yield definitive test results. Consequently, patients may not timely receive appropriate medicaments resulting in deteriorating of the condition of the patient. In case of severe diseases there is no time to await these test results and antimicrobial medicaments, such as antibiotics, will be prescribed as a precaution prior to a definitive diagnosis is set. This may, however, lead to the misuse and / or overuse of antimicrobial medicaments. The consequence thereof is antimicrobial resistance (AMR). This is highly undesirable as it may cause a critical risk for public health. Hence, there is a serious need to be able to quickly detect and identify the right pathogen in infections in order to offer the correct treatment to patients (human and / or animal) as well as preserving antimicrobial medicaments for the infections that need them the most. It is a goal of the invention to at least partially overcome the abovementioned problems, in particular to provide a simplified and a more time efficient diagnostic test.

[0005] The invention thereto provides a method for analysing therapeutical compound susceptibility of analytes in fluid samples, comprising the steps of:

[0006] A) providing at least one fluid sample,

[0007] B) isolating at least a fraction of at least one analyte from the at least one fluid sample if present in the fluid sample,

[0008] C) applying at least one fluid comprising at least one therapeutic compound to at least part of the fraction of at least one analyte such that at least a fraction of the isolated analytes extracellularly excretes and / or secretes therapeutic responsive biomolecules,

[0009] D) analysing at least part of the extracellularly excreted and / or secreted therapeutic responsive biomolecules and determining at least one susceptibility characteristic of the analysed extracellularly excreted and / or secreted therapeutic responsive biomolecules, and

[0010] E) comparing at least one determined susceptibility characteristic with at least one reference characteristic corresponding to the at least one determined susceptibility characteristic thereby determining the susceptibility of at least part of the isolated analytes to the at least one therapeutic compound, preferably, wherein the, in particular all, method steps are performed within 15 minutes, more preferably within 10 minutes.

[0011] Preferably, the fluid sample is at least one body fluid sample, such as blood, urine, sweat, and the like. The analyte may be viable cell(s). Viable cell(s) may be any type of cell, such as prokaryotic cell(s) and / or eukaryotic cell(s). The step of isolating at least a fraction of at least one analyte may be performed by filtering, centrifugation, flow cytometry, magnetic bead extraction, and / or combinations thereof. Instead of or in addition to at least one therapeutic compound, the fluid applied in step C) may comprise at least one pharmaceutical compound. The fluid comprising at least one therapeutic compound and / or at least one pharmaceutical compound may cause at least a fraction of the isolated analytes to extracellularly secrete and / or excrete biomolecules responsive to the therapeutic compound and / or pharmaceutical compound.

[0012] A preferred application of the method and device according to the present invention is related to analysing antimicrobial compound susceptibility of pathogenic microorganisms in body fluid samples.

[0013] The invention provides thereto in a preferred embodiment a method for analysing antimicrobial compound susceptibility of pathogenic microorganisms in body fluid samples, comprising the steps of:

[0014] A) providing at least one body fluid sample,

[0015] B) filtering the at least one body fluid sample through at least one catch filter which is configured for capturing at least a fraction of pathogenic microorganisms from the at least one body fluid sample if present in the body fluid sample,

[0016] C) applying at least one fluid comprising at least one antimicrobial compound to at least part of the at least one catch filter, in particular to the fraction of pathogenic microorganisms, such that at least a fraction of the captured pathogenic microorganisms extracellularly secretes antimicrobial responsive biomolecules,

[0017] D) analysing at least part of the extracellularly secreted antimicrobial responsive biomolecules and determining at least one susceptibility characteristic of the analysed extracellularly secreted antimicrobial responsive biomolecules, and

[0018] E) comparing at least one determined susceptibility characteristic with at least one reference characteristic corresponding to the at least one determined susceptibility characteristic thereby determining the susceptibility of at least part of the captured pathogenic microorganisms to the at least one antimicrobial compound, preferably, wherein the, in particular all, method steps are performed within 15 minutes, more preferably within 10 minutes.

[0019] The method according to the present invention enables an effective and efficient determination of the susceptibility of pathogenic microorganisms to an antimicrobial compound. The method allows a direct analysis of said susceptibility without the need of a culture or growth step of the pathogenic microorganisms. As a result, the method according to the invention is less time-consuming and less laboratory intensive. Preferably, at least part of the, in particular all the, method steps are performed within a period of 1 minute - 25 minutes, preferably 3 minutes - 20 minutes, more preferably 5 minutes - 17 minutes, even more preferably 8 minutes - 15 minutes, even more preferably 10 minutes - 12 minutes. It was surprisingly found that a relatively short exposure time of the captured pathogenic microorganisms to at least one antimicrobial compound is sufficient for determining the susceptibility of at least part of the captured pathogenic microorganisms to at least one antimicrobial compound. This further contributes to the time-efficiency for determining the susceptibility of the pathogenic microorganism(s) to antimicrobial compound(s). Filtering the at least one body fluid sample through at least one catch filter results in that at least part of any pathogenic microorganisms, if present in the body fluid, will be retained on and / or within the catch filter. Preferably, at least some, preferably all, method steps are performed on said catch filter. The at least one catch filter is in particular configured for capturing at least a fraction of at least one pathogenic microorganism, and in particular for capturing multiple pathogenic microorganisms. The mesh size of at least one catch filter could be specifically chosen for a target pathogenic microorganism. Once at least part of at least one pathogenic microorganism is captured on and / or within the at least one catch filter, it was experimentally found that applying at least one fluid comprising at least one antimicrobial compound, directly or indirectly, to at least part of the at least one catch filter, in particular to the fraction of pathogenic microorganisms, causes the pathogenic microorganisms to extracellularly secrete and / or excrete antimicrobial responsive biomolecules. Therefore, the method according to the present invention includes the step of applying at least one fluid comprising at least one antimicrobial compound to at least part of the at least one catch filter and / or to at least part of the fraction of captured pathogenic microorganisms, such that at least a fraction of the captured pathogenic microorganisms extracellularly secretes and / or excretes antimicrobial responsive biomolecules. In particular, at least a fraction of the captured pathogenic microorganisms extracellularly secretes and / or excretes biomolecules of which at least a fraction are antimicrobial responsive biomolecules. The presence of antimicrobial responsive biomolecules provides an indirect measure for the presence of pathogenic microorganisms in the body fluid sample. The method according to the invention also determines susceptibility of the captured pathogenic microorganisms for the applied antimicrobial compound by comparing at least one determined susceptibility characteristic of analysed extracellularly secreted and / or excreted antimicrobial responsive biomolecules with at least one reference characteristic corresponding to the at least one determined susceptibility characteristic. Preferably, the reference characteristic relates to or may include a susceptibility characteristic of at least one type of pathogenic microorganism for at least one type of antimicrobial compound and / or for at least one concentration of an antimicrobial compound. The degree of similarity between the reference characteristic and the determined susceptibility characteristic preferably correlates to the susceptibility of at least part of the captured pathogenic microorganisms to the at least one antimicrobial compound. Since the susceptibility of the pathogenic microorganisms to an antimicrobial compound is determined by means of the by the pathogenic microorganisms extracellularly secreted and / or excreted antimicrobial responsive biomolecules less laboratory intensive steps are required for analysing antimicrobial responsive biomolecules. Hence, the method for example does not require a lysis step of the pathogenic microorganisms for obtaining and analysing antimicrobial responsive biomolecules. Instead, the method analyses extracellularly secreted and / or excreted biomolecules which are responsive to the applied fluid comprising at least one antimicrobial compound. This contributes to simplifying the diagnostic test due to less laboratory intensive and less time-consuming diagnostics steps are required.

[0020] The method in particular focusses on analysing antimicrobial compound susceptibility of pathogenic microorganisms in body fluid samples. The method can be configured for use in combination with a device according to the present invention. Whilst the method could be applied for such, the method is not specifically configured for analysing antimicrobial compound susceptibility of pathogenic microorganisms which are spiked into a fluid sample.

[0021] The method benefits of being relatively simple, resulting in that the method does not require trained of qualified professionals to perform the processing of the body fluid sample according to the invention. The method could be performed in a manual way. However, it is not excluded that at least part of the method could be performed in an automated manner. Yet another benefit of the method according to the present invention is that the method only produces a relatively small amount of waste. The waste, typically the liquid waste, produced after the method is suitable for conventional medical disposal, in particular conventional biological disposal. The method according to the invention is in particular suitable for direct testing of fluid samples, in particular body fluid samples. However, it is conceivable that preparation steps, such as prefiltration, purification and / or dilution of the (body fluid) sample, are done prior to step B) and / or step C). It is also not excluded to apply the method according to the present invention in combination with a cultured sample.

[0022] Within the context of the present invention, when it is referred to pathogenic microorganisms any type of pathogenic microorganisms could be meant. Nonlimiting examples of pathogenic microorganisms are fungi and / or bacteria and / or parasites. When it is referred to a sample or a fluid sample, this could for example be a body fluid sample, more in particular a human and / or animal body fluid sample or a biological fluid, such as but not limited to saliva, blood, blood plasma, blood culture, urine, sweat, tears, cerebrospinal fluid, lymph fluid, synovial fluid, milk, amniotic fluid and / or derivatives thereof. Alternatively, the sample could be any further fluid that could contain at least one analyte, such as viable pathogens. Further non-limiting examples of fluid samples are water and / or solutions in the lab. The sample can be a pure sample. However, it is also possible that the sample is diluted and / or dissolved in a solvent. The viable pathogen could for example be bacteria, fungi, and / or parasites.

[0023] In the context of the invention the term “antimicrobial responsive biomolecules” may relate to a modulation of at least one biomolecule and / or the composition of a plurality of biomolecules excreted and / or secreted by at least one pathogenic microorganism as response to at least one antimicrobial compound. Additionally or alternatively, an “antimicrobial responsive biomolecule” may relate to a biomolecule excreted and / or secreted, in particular specifically, due to a (biological) response to the application of at least one antimicrobial compound. The pathogenic microorganisms may not excrete and / or secrete “antimicrobial responsive biomolecules” in the absence of an antimicrobial compound. It is imaginable that the type, the amount and / or the composition of secreted and / or excreted antimicrobial responsive biomolecules depend on the type and / or concentration of antimicrobial compound(s) applied to the fraction of pathogenic microorganisms. The pathogenic microorganisms may use different biological pathways for secretion and / or excretion of antimicrobial responsive biomolecules. The biological pathways may depend on the type and / or concentration of antimicrobial compound(s) applied to the fraction of pathogenic microorganisms. In particular, secreted and / or excreted antimicrobial responsive biomolecules relate to biomolecules which are released from the pathogenic microorganism as consequence of exposure to an antimicrobial substance. Antimicrobial responsive biomolecules may for example be metabolites, in particular amino acids, enzymes, organic acids, peptides and / or alkaloids. It is for example also possible that the small excreted and / or secreted biomolecules are nucleotide derivatives, such as purine and pyrimidine components, and amino acid derivatives.

[0024] The analysing step and / or the identifying step of the method may be a direct analysing step and / or identifying step configured to directly analyse and / or identify at least part of the extracellularly secreted and / or excreted antimicrobial responsive biomolecules. The analysed and / or identified secreted and / or excreted antimicrobial responsive biomolecules are in particular directly related to a response of the pathogenic microorganism to the applied fluid comprising at least one antimicrobial compound. Said direct analysing step and / or identifying step is in particular not related to analysing and / or identify a compound, such as a reporter compound, which is converted by extracellularly secreted and / or excreted antimicrobial biomolecules. The present invention is in particular configured to analyse, and optionally to identify, solely the extracellularly secreted and / or excreted antimicrobial responsive biomolecules. Optionally, the present invention may be configured to additionally analyse, and optionally identify, also the pathogenic microorganisms.

[0025] Filtering of the at least one body fluid sample through at least one catch filter such that at least part of any pathogenic microorganisms, if present in the body fluid sample, is retained within and / or on the catch filter is an example of isolating at least a fraction of pathogenic microorganisms from the at least one body fluid sample, if present in the body fluid sample. Alternatively, step B) of isolating at least a fraction of pathogenic microorganisms from the at least one body fluid sample could be provided via centrifugation, flow cytometry, magnetic bead extraction and / or combinations thereof. Within the context of the present invention, when it is referred to a characteristic, such as a determined susceptibility characteristic and / or a reference characteristic, a parameter or a feature could be meant. The susceptibility characteristic is preferably at least partially related to at least one characteristic of the at least one antimicrobial compound of the at least one fluid applied in step C).

[0026] It is conceivable that at least one reference characteristic is derivable from a database comprising reference characteristics. Hence, the method may comprise a step of obtaining at least one reference characteristic from a database comprising reference characteristics, wherein said step of obtaining at least one reference characteristic is performed prior to or during or in parallel with step E). Additionally or alternatively, at least one reference characteristic may be determined from a baseline measurement. The baseline measurement may also be referred to as background signal. Hence, the method may comprise a step of determining at least one reference characteristic.

[0027] The method steps of the present invention are in particular subsequent steps. Hence, in an embodiment, steps A) to E) are subsequent steps. The method enables that no growth or cultivation step of the pathogenic microorganisms, if captured, is needed but that instead at least one fluid comprising an antimicrobial compound is applied which also enables accurate and effective analysis of susceptibility of pathogenic microorganisms if present in the body fluid sample.

[0028] At least one susceptibility characteristic may relate to the amount of antimicrobial responsive biomolecules extracellularly secreted by a fraction of the captured pathogenic microorganisms. Optionally, at least one susceptibility characteristic relates to the ratio of the amount of antimicrobial responsive biomolecules relative to the amount of captured pathogenic microorganisms. In particular, at least one susceptibility characteristic is a quantitative susceptibility characteristic. In the case that at least one susceptibility characteristic relates to the amount of antimicrobial responsive biomolecules extracellularly secreted by a fraction of the captured pathogenic microorganisms, at least one reference characteristic preferably also relates to or includes an amount of extracellularly secreted antimicrobial responsive biomolecules. It is imaginable that at least one reference characteristic relates to or includes an amount of antimicrobial responsive biomolecules expected or known to be extracellularly secreted and / or excreted by pathogenic microorganisms, in particular by a certain type of pathogenic microorganism. Optionally, the reference characteristic relates to or includes an amount of antimicrobial responsive biomolecules extracellularly secreted and / or excreted by antimicrobial resistant pathogenic microorganisms, in particular of pathogenic microorganisms resistant to the applied antimicrobial compound. A sufficient degree of similarity between the determined susceptibility characteristic and the reference characteristic provides information about the susceptibility of the captured pathogenic microorganisms to the applied antimicrobial compound. Hence, this preferred embodiment contributes to an effective and efficient determination of the susceptibility of pathogenic microorganisms to an antimicrobial compound. This embodiment may additionally provide information about the type of pathogenic microorganism(s) present in the body fluid sample. Based thereon, correct antimicrobial medicaments to be applied and / or incorrect antimicrobial medicaments not to apply can be selected.

[0029] At least one susceptibility characteristic may relate to the type of antimicrobial responsive biomolecules extracellularly secreted by a fraction of the captured pathogenic microorganisms. Optionally, at least one susceptibility characteristic is a qualitative susceptibility characteristic. The type of antimicrobial responsive biomolecules may also refer to the species of antimicrobial responsive biomolecules extracellularly secreted by a fraction of the captured pathogenic microorganisms. In the case that at least one susceptibility characteristic relates to the type of antimicrobial responsive biomolecules extracellularly secreted by a fraction of the captured pathogenic microorganisms, at least one reference characteristic preferably also relates to or includes a type of extracellularly secreted antimicrobial responsive biomolecules. It is imaginable that at least one reference characteristic relates to or includes a type of antimicrobial responsive biomolecule expected or known to be extracellularly secreted and / or excreted by pathogenic microorganisms, in particular by a certain type of pathogenic microorganism. This embodiment contributes to an effective and efficient determination of the susceptibility of pathogenic microorganisms to an antimicrobial compound. This embodiment may additionally provide information about the type of pathogenic microorganism(s) present in the body fluid sample. Based thereon, correct antimicrobial medicaments to be applied and / or incorrect antimicrobial medicaments not to apply can be selected. At least one susceptibility characteristic may relate to a ratio of the amount and / or the type of antimicrobial responsive biomolecules extracellularly secreted by a fraction of the captured pathogenic microorganisms relative to non-antimicrobial responsive biomolecules secreted by a fraction of the captured pathogenic microorganisms. Non-antimicrobial responsive biomolecules may be defined as the remaining biomolecules secreted by the captured pathogenic microorganisms which do not correspond to a response to an, in particular the applied, antimicrobial compound. At least one reference characteristic preferably also relates to or includes a ratio of the amount and / or the type of antimicrobial responsive biomolecules extracellularly secreted by pathogenic microorganisms relative to non-antimicrobial responsive biomolecules secreted by the same type of pathogenic microorganisms. It is imaginable that at least one reference characteristic relates to or includes a ratio of the amount and / or the type of antimicrobial responsive biomolecule expected or known to be extracellularly secreted and / or excreted by pathogenic microorganisms, in particular by a certain type of pathogenic microorganism. This embodiment contributes to an effective and efficient determination of the susceptibility of pathogenic microorganisms to an antimicrobial compound. This embodiment may additionally provide information about the type of pathogenic microorganism(s) present in the body fluid sample. Based thereon, correct antimicrobial medicaments to be applied can be selected.

[0030] At least one susceptibility characteristic may relate to the composition of antimicrobial responsive biomolecules extracellularly secreted by a fraction of the captured pathogenic microorganisms. The composition can be defined as the different types, and optionally the amount of the different types, of antimicrobial responsive biomolecules extracellularly secreted by a fraction of the captured of pathogenic microorganisms. At least one reference characteristic preferably also relates to or includes a composition of antimicrobial responsive biomolecules extracellularly secreted by pathogenic microorganisms. It is imaginable that at least one reference characteristic relates to or includes a composition of antimicrobial responsive biomolecule expected or known to be extracellularly secreted and / or excreted by pathogenic microorganisms, in particular by a certain type of pathogenic microorganism. This embodiment contributes to an effective and efficient determination of the susceptibility of pathogenic microorganisms to an antimicrobial compound. This embodiment may additionally provide information about the type of pathogenic microorganism(s) present in the body fluid sample.

[0031] Based thereon, correct antimicrobial medicaments to be applied can be selected.

[0032] Preferably, in step D) at least one susceptibility profile is determined which is formed by a combination of a plurality of susceptibility characteristics, and wherein in step E) at least one susceptibility profile is compared with at least one reference profile which is formed by a combination of reference characteristics. A plurality of susceptibility characteristics may comprise at least two different types of susceptibility characteristics. Said different types of susceptibility characteristics may relate to at least two different types of susceptibility characteristics chosen from the group which comprises: the amount, the type, the ratio of the amount and / or type, and / or the composition of antimicrobial responsive biomolecules extracellularly secreted by a fraction of the captured pathogenic microorganisms. Within the context of the invention, a susceptibility profile or a reference profile may be referred to as a susceptibility pattern or reference pattern and / or a susceptibility signature or reference signature, respectively. This embodiment is beneficial as a susceptibility profile, and a corresponding reference profile, comprise a plurality of characteristics and hence more information, which contributes to improving the accuracy of the determined susceptibility of at least part of the captured pathogenic microorganisms to the at least one antimicrobial compound applied.

[0033] The method according to the present invention preferably comprises a step F) of identifying at least a fraction of the extracellularly secreted antimicrobial responsive biomolecules and determining the type of antimicrobial responsive biomolecules extracellularly secreted by at least a fraction of the captured pathogenic microorganisms and / or determining the composition of antimicrobial responsive biomolecules extracellularly secreted by at least a fraction of the captured pathogenic microorganisms, wherein step F) is performed after step C). This identification step may for example be performed by means of Raman Spectroscopy, SERS and / or biochemical analysis. Preferably, step F) is based on the extracellularly secreted antimicrobial responsive biomolecules. This step is preferably performed after or simultaneously with step D). In particular, the type and / or composition of antimicrobial responsive biomolecules is characteristic for each type of pathogenic microorganism. The type and / or composition of antimicrobial responsive biomolecules may also depend on the type and / or of antimicrobial compound applied to the particular type of pathogenic microorganism. Hence, the extracellularly secreted and / or excreted antimicrobial responsive biomolecules provides information on the type, species, and / or identity of the pathogenic microorganism. Additionally, the extracellularly secreted and / or excreted antimicrobial responsive biomolecules may also provide information about the susceptibility of the pathogenic microorganism to the applied antimicrobial compound. Optionally, the step of identifying at least one type of captured pathogenic microorganisms is performed by comparing the identified extracellularly secreted and / or excreted antimicrobial responsive biomolecules with at least one database comprising reference characteristics which include data of the type and / or composition of antimicrobial responsive biomolecules per type of pathogenic microorganism. It is imaginable that the method comprises a step of identifying non-antimicrobial responsive biomolecules and determining the type of nonantimicrobial responsive biomolecules extracellularly secreted by at least a fraction of captured pathogenic microorganisms and / or determining the composition of nonantimicrobial responsive biomolecules extracellularly secreted by at least a fraction of captured pathogenic microorganisms. This step of identifying non-antimicrobial responsive biomolecules is in particular of relevance when the method comprises the step of determining a reference characteristic or reference profile as non- antimicrobial responsive biomolecules preferably comprise at least one reference characteristic.

[0034] The method may comprise a step G) of analysing at least one fluid comprising at least one antimicrobial compound to be applied to and / or applied to at least part of the at least one catch filter and determining at least one reference characteristic of said analysed fluid. Step G) may be performed during and / or in parallel with and / or prior to and / or directly after step C). Directly after step C) particularly means within 5 minutes after step C), preferably within 2 minutes, more preferably within 1 minute. Performing step G) prior to and / or directly after step C) allows the determination of a reference characteristic of the fluid comprising at least one antimicrobial compound without or with limited interference of pathogenic microorganisms. In particular, step G) is performed prior to the extracellularly secretion and / or excretion of antimicrobial responsive biomolecules by the captured pathogenic microorganisms. Therewith, step G) is a baseline measurement and / or provides a possibility to determine a background signal corresponding to the fluid to be applied and / or applied in step C). Step G) may provide information about the interference of the at least one fluid comprising at least one antimicrobial compound to the in step D) determined susceptibility characteristic. Said step of determination of a background signal may also be referred to as a baseline measurement. Said background signal or baseline measurement may comprise at least one reference characteristic. Preferably, in step G) the analysed fluid is free from pathogenic microorganisms and / or extracellularly secreted antimicrobial responsive biomolecules. Therewith, interference of pathogenic microorganisms and / or extracellularly secreted and / or excreted antimicrobial responsive biomolecules to the background signal or baseline measurement and / or the determined reference characteristic(s) is minimized. This embodiment contributes to improving the accuracy of the method.

[0035] The method may comprise a step H) of providing at least one reference fluid which corresponds to the fluid to be applied or applied in step C), wherein the reference fluid is free from antimicrobial compound. Preferably, the method further comprises a step of analysing said reference fluid and determining at least one reference characteristic corresponding to the reference fluid. In step H) the reference fluid is preferably also free from pathogenic microorganisms and / or extracellularly secreted and / or excreted antimicrobial responsive biomolecules. Hence, the step of analysing said reference fluid and determining at least one reference characteristic thereof is preferably performed in a separate environment from the body fluid sample (to be) analysed. The determination of a reference characteristic of the reference fluid provides a possibility to determine a background signal corresponding to the fluid without interference of an antimicrobial compound. Determination at least one reference characteristic of said at least one reference fluid provides information about the interference of said fluid to the in step D) determined susceptibility characteristic. Said step of determination of a background signal may also be referred to as a baseline measurement. Hence, this preferred embodiment provides the determination of a reference characteristic corresponding to a background signal. This embodiment contributes to improving the accuracy of the method.

[0036] The method preferably comprises a step I) of analysing the at least one catch filter and determining at least one reference characteristic of said at least one catch filter, wherein step I) is performed prior to step C). The catch filter is then free from the at least one fluid comprising at least one antimicrobial compound. Hence, the catch filter is also free from extracellularly secreted and / or excreted antimicrobial responsive biomolecules. Preferably, step I) is performed prior to step B). In that case, the catch filter is (also) substantially free from pathogenic microorganisms. Step I) provides a possibility to determine a background signal corresponding to the catch filter. Determination at least one reference characteristic of said at least one catch filter provides information about the interference of said catch filter to the in step D) determined susceptibility characteristic. Said step of determination of a background signal may also be referred to as a baseline measurement. Hence, this preferred embodiment provides the determination of a reference characteristic corresponding to a background signal. This embodiment contributes to improving the accuracy of the method.

[0037] Step D) according to the method of the invention may be repeated at least at two different time points. In particular, a first step D) may be performed shortly after step C) and a following second step D) may be performed some time after first step D). Second step D), and possible following steps D), are in particular performed within a maximum of 30 minutes after step C), preferably within a maximum of 20 minutes after step C), more preferably within 15 minutes after step C), even more preferably within 10 minutes after step C). It has been experimentally found that pathogenic microorganisms are capable of extracellularly excreting and / or secreting detectable and / or identifiable antimicrobial responsive biomolecules within 10 minutes after the exposure to a fluid comprising an antimicrobial compound. This embodiment enables to follow the excretion and / or secretion of antimicrobial responsive biomolecules in time, and in a time efficient manner. Instead of determining a susceptibility characteristic in first step D), said first step D) may be performed to determine a reference characteristic according to step G). In that case, first step D) is replaced by step G).

[0038] The method preferably comprises a step J) of dividing at least one body fluid sample in at least two separate sample parts, and wherein at least steps B) and C) are performed separately and / or independently for at least two separate sample parts. In particular, step J) divides the at least one body fluid sample provided in step A) in at least two separate sample parts. Alternatively, step A) provides at least two separate body fluid samples, wherein at least steps B) and C) are performed separately and / or independently for at least two separate body fluid samples. Alternatively, step A) further comprises providing at least one second body fluid sample, wherein at least steps B) and C) are performed separately and / or independently for the at least two body fluid samples. In particular, in separately and / or independently performed step B) the at least two separate sample parts or the at least two separate body fluid samples or the at least two body fluid samples are (each) filtered through a separate and / or independent catch filter. For example, in a first separate step B) at least one first separate sample part is filtered through at least one first catch filter and in a second separate step B), which is separate and / or independent from first step B), at least one second separate sample part is separately and / or independently from said first separate sample part filtered through at least one second catch filter, wherein said first catch filter and second catch filter are separate and / or independent catch filters. For example, in a first separate step C) at least one fluid comprising at least one antimicrobial compound is applied to at least one first catch filter through which, during first step B) at least one first separate sample part is filtered, and in a second separate step C), which is separate and / or independent from first step C), at least one fluid comprising at least one antimicrobial compound is applied to at least one second catch filter through which, during second step B) at least one second separate sample part is filtered. This embodiment provides at least two separate sample parts and hence at least two separate environments for analysing antimicrobial compound susceptibility of pathogenic microorganisms of at least one body fluid sample. This embodiment efficiently uses the at least one body fluid sample by enabling the option to perform a plurality of diagnostic tests and therewith contributes to simplifying diagnostic tests. It is imaginable that in step J) the at least one body fluid sample is divided in a plurality of sample parts, wherein step B) and step C) are separately performed for said plurality of sample parts. Optionally, in step J) at least one body fluid sample is proportionally divided into a plurality of sample parts. Step J) is particularly performed after step A). Optionally, at least steps B) to D) are separately performed for each sample part obtained after step J).

[0039] The concentration of at least one antimicrobial compound in the fluid applied in step C) is preferably different for the separately and / or independently performed step C) for at least two separate sample parts. It is imaginable that the concentration of at least one antimicrobial compound in the fluid applied in step C) is different for the separately performed steps C) for each of the separate sample parts. Preferably, only the concentration of the at least one antimicrobial compound in the fluid applied in step C) differs for the separately performed step C) for the at least two separate sample parts. In this embodiment, it is preferred that aside from the concentration the composition of the fluid applied in step C) is the same for the separately performed step C) for the at least two separate sample parts. For example, in a first separate and / or independent step C) at least one fluid comprising a first concentration of at least one antimicrobial compound is applied to at least one catch filter of a first separately and / or independently performed step B), and in a second step C), which is separate and / or independent from first step C), at least one fluid comprising a second concentration of the at least one antimicrobial compound is applied to at least one separate and / or independent catch filter of a second separately and / or independently performed step B), wherein the first concentration and the second concentration differ from each other. Preferably, at least one fluid applied in step C) comprises a minimum inhibitory concentration (MIC) of at least one antimicrobial compound, wherein the MIC of the at least one antimicrobial compound in the fluid is close to or equal to a MIC breakpoint. The MIC can be defined as the minimal concentration of an antimicrobial compound which inhibits the growth of a particular species of or a specific type of pathogenic microorganism, in particular of a particular species or specific type of bacterium, more in particular of a specific bacterial strain. MIC breakpoint(s) can be defined as a categorization or discriminatory of the MIC of a particular antimicrobial compound at which a particular species of or a specific type of pathogenic microorganism is susceptible at normal dosing (S), susceptible at increased exposure (I) or resistant (R). Susceptibility at an increased exposure (I) particularly means susceptibility of the pathogenic microorganisms to at least one antimicrobial compound due to an increased exposure. This may for example be caused by adjusting the concentration of the antimicrobial compound and / or by adjusting the dosing interval and / or by adjusting the infusion time. In particular, susceptibility at increased exposure (I) may be achieved by exposing at least a fraction of the captured pathogenic microorganisms to a higher concentration or a higher dose than the concentration or dose at normal dosing (S) of the at least one antimicrobial compound. MIC breakpoints of specific types of pathogenic microorganisms for particular antimicrobial compounds are well known in the art. Preferably, the concentration of at least one antimicrobial compound in the fluid applied in step C) is close to or equal to a MIC breakpoint and different for the separately and / or independently performed step C) for at least two separate sample parts. For example, in step C) a first concentration, which is close to or equal to a first MIC breakpoint of at least one antimicrobial compound is applied to a first separate sample part, and a second concentration, which is close to or equal to a second MIC breakpoint of the at least one antimicrobial compound is applied to a second sample part, wherein the first MIC breakpoint and the second MIC breakpoint differ from each other. Preferably, the first MIC breakpoint relates to a concentration at which at least a fraction of the captured pathogenic microorganisms are expected to be resistant (R) to the at least one antimicrobial compound applied and the second MIC breakpoint relates to a concentration, in particular a normal dosing concentration, at which at least a fraction of the captured pathogenic microorganisms are expected to be susceptible (S) to the at least one antimicrobial compound applied. Alternatively, the first MIC breakpoint or the second MIC breakpoint relate to an increased exposure of at least a fraction of the captured pathogenic microorganisms to the at least one antimicrobial compound at which at least a fraction of the captured pathogenic microorganisms are expected to be susceptible (I) to the at least one antimicrobial compound applied. It is imaginable that step C) is separately and / or independently performed for three separate sample parts. In that case, it is preferred that the concentration of at least one antimicrobial compound in the fluid applied in step C) is close to or equal to a MIC breakpoint and different for the separately and / or independently performed step C) for the three separate sample parts. Hence, in step C) a first concentration, which is close to or equal to a first MIC breakpoint, of at least one antimicrobial compound is applied to a first separate sample part, a second concentration, which is close to or equal to a second MIC breakpoint, of the at least one antimicrobial compound is applied to a second sample part, and a third concentration, which is close to or equal to a third MIC breakpoint, of the at least one antimicrobial compound is applied to a third sample part, wherein the first MIC breakpoint, the second MIC breakpoint and the third MIC breakpoint differ from each other. Preferably, the first MIC breakpoint relates to a concentration at which at least a fraction of the captured pathogenic microorganisms are expected to be resistant (R) to the at least one antimicrobial compound applied, the second MIC breakpoint relates to a concentration at which at least a fraction of the captured pathogenic microorganisms are expected to be susceptible (S) to the at least one antimicrobial compound applied, and the third MIC breakpoint relates to an increased exposure of at least a fraction of the captured pathogenic microorganisms to the at least one antimicrobial compound at which at least a fraction of the captured pathogenic microorganisms are expected to be susceptible (I) to the at least one antimicrobial compound applied. It is preferred that at least one reference characteristic of step E) is a MIC breakpoint of the applied antimicrobial compound. This embodiment allows to determine the concentration at which an antimicrobial compound is effective against a pathogenic microorganism. Hence, it provides information about the dose of the antimicrobial compound to be applied to be effective. Therewith, this embodiment contributes in reducing the overuse of antimicrobial compounds.

[0040] Preferably, the type of antimicrobial compound in the fluid applied in step C) is different for the separately and / or independently performed step C) for at least two separate sample parts. It is imaginable that the type of at least one antimicrobial compound in the fluid applied in step C) is different for the separately performed steps C) for each of the separate sample parts. Preferably, only the type of antimicrobial compound in the fluid applied in step C) differs for the separately performed step C) for the at least two separate sample parts. In this embodiment, it is preferred that aside from the type of antimicrobial compound the composition of the fluid applied in step C) is the same for the separately performed step C) for the at least two separate sample parts. For example, in a first separate and / or independent step C) at least one fluid comprising a first type of antimicrobial compound is applied to at least one catch filter of a first separately and / or independently performed step B), and in a second step C), which is separate and / or independent from first step C), at least one fluid comprising a second type of antimicrobial compound is applied to at least one separated and / or independent catch filter of a second separately and / or independently performed step B), wherein the first type of antimicrobial compound and the second type of antimicrobial compound differ. This embodiment contributes to identifying which type of antimicrobial compound is susceptible or resistant for pathogenic microorganism(s) present in the analysed body fluid sample. Therewith, correct antimicrobial medicaments can be prescribed and / or administered which contributes in reducing the misuse of antimicrobial medicaments. Preferably, during at least one separately performed step C) at least one reference fluid is applied instead of at least one fluid comprising at least one antimicrobial compound, thereby forming a reference sample part. Said reference fluid is in particular provided in step H). Preferably, during at least one other separately performed step C) at least one fluid comprising at least one antimicrobial compound is applied, thereby forming a susceptibility sample part. In particular, step H) is performed after step J). The method preferably further comprises a step of analysing the reference sample part and determining at least one reference characteristic of the analysed reference sample part. This provides the possibility to analyse the extracellularly secreted and / or excreted biomolecules which are not responsive to the antimicrobial compound. This embodiment enables to distinguish extracellularly secreted and / or excreted biomolecules responsive to the antimicrobial compound from extracellularly secreted and / or excreted biomolecules which are not responsive to the antimicrobial compound. Hence, this preferred embodiment contributes to improving the accuracy of the method.

[0041] Step D) may be performed by means of Raman Spectroscopy, in particular Surface-Enhanced Raman Spectroscopy (SERS), and / or biochemical analysis and / or electrical analysis. An electrical analysis may for example be a redox additive analysis. Additionally or alternatively, step D) may be performed by means of a chemical analysis. In this way, an effective and reliable analysis could be performed. It is imaginable that the prepared catch filter can be directly used as substrate in the analysis step. It is also possible that a further processing step is needed to prepare the catch filter for further analysis. The substrate used in the analysis step may be functionalized to amplify a signal to be measured and / or to improve sensitivity of the analysis.

[0042] The method may comprise step K) of concentrating at least part of at least one fluid in which the captured pathogenic microorganisms and / or the extracellularly secreted antimicrobial responsive biomolecules are suspended, such that the concentration of captured pathogenic microorganisms and / or the concentration of extracellularly secreted antimicrobial responsive biomolecules is increased. It is imaginable that the fluid wherein the captured pathogenic microorganisms and / or the extracellularly secreted antimicrobial responsive biomolecules are suspended is the fluid applied in step C). The fluid wherein the captured pathogenic microorganisms and / or the extracellularly secreted antimicrobial responsive biomolecules are suspended may also be referred to as supernatant. Including this step could positively affect the further analysis of the pathogenic microorganisms and / or extracellularly secreted stress responsive biomolecules. Step K) may be performed by evaporating at least a part of the at least one fluid. Step K) may be performed by air drying and / or air plunging. Step K) is preferably performed by heating. In particular, by heating at least part of the fluid, in particular such that at least part of the fluid evaporates. It is also possible that at least part of the catch filter is heated. This may also cause evaporation of at least part of the fluid. Hence, the method could optionally comprise a concentrating step. This is for example conceivable in case at least part of the pathogenic microorganisms and / or the secreted antimicrobial responsive biomolecules are provided and / or at least partially dissolved in a fluid. Optionally, the fluid, preferably the fluid which is applied in step C), comprises glycerol. Glycerol evaporates at higher temperatures than a majority of other components of the fluid, such as water. Hence, in case the fluid comprises glycerol the amount of fluid that evaporates in step K) can be controlled. Therewith, a well-defined volume after evaporation is obtainable. Therewith, it is provided that the catch filter does not dry out. In an alternative embodiment, at least one concentration step could be applied via freeze drying. In this way, an effective and reliable analysis could be performed. Applying step K) contributes in improving the sensitivity of the analysis in step D).

[0043] In the context of the present invention, a specimen may be defined comprising at least the captured pathogenic microorganisms, the secreted and / or excreted antimicrobial responsive biomolecules and the fluid comprising at least one antimicrobial compound, and optionally at least one (body) fluid sample. At least during and / or after step C) the volume of said specimen may be less than 3 ml, preferably less than 2 ml, more preferably less than 1 ml. In a preferred embodiment the volume of said specimen during and / or after step C) may be lower than 1 pl, preferably lower than 100 nl, more preferably less than 10 nl, most preferred less 1 nl. However, it is also conceivable that the volume of said specimen during and / or after step C) is in the range of 5 ml en 1 pl, preferably in the range of 1 ml to 30 pl and / or in the range of 0.5 ml to 50 pl. It is possible that only a faction of said volume is actively used. The volume of the specimen during and / or after step C) is in particular larger than after optional step K). The method may further comprise a step L) of purifying the at least one body fluid sample for removing at least a fraction of particles from the body fluid sample, in particular particles which are larger than pathogenic microorganisms. Step L) may be performed by filtering the at least one body fluid sample through at least one coarse filter. Step L) is preferably performed prior to step B). Such a coarse filter may be configured for removing at least a fraction of particles from the body fluid sample, in particular particles which are larger than pathogenic microorganisms. Optionally, the body fluid sample is filtered or flushed through at least one coarse filter prior to the sample being filtered through the catch filter. At least one coarse filter, if applied, is in particular configured to remove at least a fraction of particles from the sample, in particular particles which are larger than at least one analyte. This is beneficial as the analytes, in particular the pathogenic microorganisms, could be isolated and / or captured more efficiently. Within the context of this invention, when it is referred to filtering, flushing fluid through a filter and / or drawing fluid up though a filter can be meant. Within the context of this invention, filtering could also be explained as depositing of a fluid onto at least one filter. It is for example imaginable that at least part of the fluid which is to be filtered is absorbed by at least one filter.

[0044] It is conceivable that at least one coarse filter, if applied, comprises at least one coarse-grained fabric material, such as but not limited to: glass wool, cotton, synthetic wool and the like. In a beneficial embodiment, at least one coarse filter, if applied, comprises glass fiber and / or glass wool. It is for example possible that at least one coarse filter is formed by glass wool comprising or being formed by glass fiber. Glass wool and glass fiber were found to be efficient in a filtering step wherein relatively large particles are to be separated from a sample, in particular a body fluid sample. The use of glass wool and / or glass is also beneficial from economical point of view since said products are relatively cheap. It is also conceivable that at least one coarse filter comprises cellulose. Other non-limitative embodiments include at least one coarse filter comprising polycarbonate and / or a coarse filter which is at least partially made of a filter paper, coffee filter or coffee paper. It is also conceivable that at least one coarse filter as applied in a method according to the present invention comprising multiple filtering materials. Hence, the coarse filter could for example be a combination of glass wool and cellulose. It is further imaginable that at least one coarse filter comprises glass fiber and / or wherein at least one catch filter comprises a glass fiber mesh, glass wool, nylon, polyamide, cellulose acetate, polysulphone, teflon and / or cellulose.

[0045] At least one coarse filter is configured to capture particles with a particle size larger than 10 pm, preferably larger than 5 pm, more preferably larger than 2 pm, even more preferably larger than 1 pm. It is also conceivable that at least one coarse filter is configured to capture particles with a particle size (significantly) larger than 10 pm. At least on coarse filter is in particular configured to let through, particles with a particle size smaller than 5 pm, preferably smaller than 2 pm, more preferably smaller than 1 pm. In this manner, any pathogenic microorganism present in the sample, which are typically smaller than said particle size, will be let through towards the catch filter step while larger contaminants will be removed from the sample. When it is referred to particle size, for example an average particle size can be meant. It is also conceivable that one coarse filter is configured to capture particles with a particle size in the range of 1 pm to 10 pm, preferably 2 pm to 5 pm. It is also conceivable that at least one coarse filter is configured to capture particles with an average width and / or length in the range of 1 pm to 10 pm.

[0046] At least one catch filter comprises glass in a preferred embodiment. It is also conceivable that at least one catch filter is at least partially made of glass. The catch filter could for example comprise glass particles, for example glass nanoparticles. At least one catch filter could for example comprise a glass (fiber) mesh. The catch filter is preferably a relatively dense filter. It is further imaginable that at least one catch filter comprises glass fiber and / or wherein at least one catch filter comprises a glass fiber mesh, glass wool, nylon, polyamide, cellulose acetate, polysulphone, polyethersulphone, teflon, polyvinylidene fluoride (PVDF), polyester (PET), polycarbonate track-etched membrane, polycarbonate (PC), and / or cellulose. It is imaginable that at least one filter is substantially hydrophobic. Preferably, at least part of at least one catch filter is substantially hydrophobic.

[0047] At least one catch filter is preferably configured to capture particles with a particle size smaller than 5 pm, preferably smaller than 3 pm, more preferably smaller than 2.5 pm, even more preferably smaller than 2 pm and most preferably smaller than 0.5 pm. In yet a further preferred embodiment, at least one catch filter is configured to capture particles with a particle size smaller than 1 pm, more in particular smaller than 0.7 pm, more in particular smaller than 0.4 pm. It may also be said that the catch filter is configured to catch particles with a predetermined particle size, for example in any of the abovementioned ranges and / or any of the ranges mentioned for the (target) analyte, in particular for the pathogenic microorganisms.

[0048] In a preferred embodiment, at least one coarse filter, if applied, and / or at least one catch filter can be present in a syringe filter. It is for example also imaginable that at least one coarse filter and / or at least one catch filter are comprised in a syringe filter. At least one coarse filter and / or at least one catch filter could for example also be a syringe filter. The filtering step could for example be applied by pushing the sample across at least one filter by the syringe. The use of at least one syringe filter in combination with a syringe could enable manual application of the method in a relatively simple manner. It is also conceivable that at least one coarse filter and / or at least one catch filter is present in a syringe filter device. Preferably, at least one filter is provided with a housing. The use of a housing could further contribute to the ease of the use of the filter. Optionally or alternatively, a filter applied within the scope of this invention could be a drip filter.

[0049] Preferably, at least a part of the catch filter is coated with nanoparticles, in particular SERS-active nanoparticles to form a SERS substrate. The nanoparticles enable that the catch filter can be used in further analysis steps, in particular SERS analysis. This results in enhanced possibilities to analyse the presence of any pathogenic microorganisms. At least part of the nanoparticles could be metal nanoparticles. It is also conceivable that substantially all nanoparticles are metal nanoparticles. Preferably at least part of the nanoparticles are noble metal nanoparticles. Metal nanoparticles, and in particular noble metal nanoparticles were found to be rather efficient for use in Raman / SERS spectroscopy. It is for example conceivable that at least part of the nanoparticles is selected from the group of silver, nickel, aluminium, gold, platinum, palladium, titanium, copper, cobalt, zinc, and / or combinations thereof. It is for example also conceivable that at least part of the nanoparticles comprises an alloy, in particular of any of the listed preferred metals. In a preferred embodiment, at least part of the nanoparticles are gold nanoparticles. It is also conceivable that at least part of the nanoparticles comprises a combination of (noble) metal and silica, such as silica shelled (metal) nanoparticles. It is also imaginable that at least part of the nanoparticles are metal nanoparticles comprising a porous silica shell. In a possible embodiment, the method comprises step M) of filtering at least one solution comprising nanoparticles, in particular SERS-active nanoparticles through the catch filter such that at least part of the catch filter will be coated with nanoparticles, in particular SERS-active nanoparticles. The at least partially coated catch filter could subsequently be used as SERS substrate. Optionally, the at least one fluid comprising at least one antimicrobial compound applied in step C) comprises nanoparticles, in particular SERS-active nanoparticles, such that at least a fraction of the captured pathogenic microorganisms extracellularly secrete antimicrobial responsive biomolecules and simultaneously coat the catch filter with said nanoparticles. Step M) may be performed prior to or during or in parallel with or after step B). If the method comprises step K), at least part of the solution applied in step M) is concentrated such that the concentration of captured pathogenic microorganisms and / or the concentration of extracellularly secreted antimicrobial responsive biomolecules is increased.

[0050] The invention also relates to a device for processing at least one body fluid sample for analysing antimicrobial compound susceptibility of pathogenic microorganisms in the at least one body fluid sample, comprising: at least one housing, comprising: at least one retaining structure for separately and / or independently retaining at least one analysis catch filter and at least one reference catch filter, at least one analysis reservoir configured for receiving at least one fluid comprising at least one antimicrobial compound, and at least one reference reservoir configured for receiving at least one reference fluid, wherein the analysis reservoir and the reference reservoir are located at a distance from each other, optionally, at least one analysis catch filter and at least one reference catch filter configured to capture at least a fraction of pathogenic microorganisms from a body fluid sample, wherein at least one housing is a modular housing which is adjustable between: a filtering configuration, wherein at least one body fluid sample can be filtered through at least one analysis catch filter retained in at least one retaining structure and wherein at least one body fluid sample can be filtered through at least one reference catch filter retained in at least one retaining structure; and a processing configuration, wherein at least one retaining structure is positioned adjacent to at least part of at least one analysis reservoir such that fluid comprising at least one antimicrobial compound received in at least one analysis reservoir can get into contact with at least part of at least one analysis catch filter retained in the at least one retaining structure, and wherein at least one retaining structure is positioned adjacent to at least part of at least one reference reservoir such that at least one reference fluid received in at least one retaining reservoir can get into contact with at least part of at least one reference catch filter retained in the at least one retaining structure.

[0051] The device according to the present invention can be used to perform a method according to the present invention, preferably at least in steps B) and C) of the method. The method according to the present invention could be performed by making use of a device according to the present invention. The device in particular enables processing of at least one body fluid sample such that analysis of antimicrobial compound susceptibility of pathogenic microorganisms can done in a relatively simple and effective manner.

[0052] The use of a modular housing which is adjustable between a filtering configuration and a processing configuration enables that the at least one analysis catch filter and at least one reference catch filter can be effectively used in the processing of at least one body fluid sample and that subsequently preparation of the captured pathogenic microorganism analysis can be achieved such that analysis thereof can be done. The device according to the present invention can be adjusted to a processing configuration wherein at least part of at least one retaining structure is positioned substantially adjacent to at least part of the at least one analysis reservoir, in particular such that fluid comprising at least one antimicrobial compound received in the at least one analysis reservoir can get into contact with at least part of at least one analysis catch filter retained in the at least one retaining structure and / or with at least part of the captured pathogenic microorganism. In the processing configuration at least part of at least one retaining structure is furthermore positioned substantially adjacent to at least part of at least one reference reservoir, in particular such that a reference fluid received in the at least one reference reservoir can get into contact with at least part of at least one reference catch filter, which is separately and / or independently retained from the at least one analysis catch filter retained in the retaining structure, retained in the at least one retaining structure and / or with at least part of the captured pathogenic microorganism. It is for example possible that at least part of at least one retaining structure is positioned substantially parallel to at least part of the analysis reservoir and / or at least part of the reference reservoir.

[0053] The at least one retaining structure is configured for separately and / or independently retaining at least one analysis catch filter and at least one reference catch filter. The retaining structure may be configured for retaining at least one analysis catch filter and at least one reference catch filter at a distance from each other, in particular next to each other. Preferably, at least one analysis catch filter and at least one reference catch filter are configured to be retained in the retaining structure such that they do not overlap. The housing further comprises at least one analysis reservoir and at least one reference reservoir located at a distance from each other. The analysis reservoir and the reference reservoir are preferably separate and / or independent reservoirs. In particular, the analysis reservoir and the reference reservoir do not overlap.

[0054] The device, in particular the housing, could optionally comprise at least one analysis catch filter and / or at least one reference catch filter configured to capture at least a fraction of pathogenic microorganisms from a body fluid sample. Any of the possible catch filters as described for the corresponding method according to the present invention could be applied. The at least one retaining structure is in particular configured for retaining at least one analysis catch filter and / or at least one reference catch filter. It is for example possible that at least one retaining structure could clampingly engage at least part of at least one analysis catch filter and / or at least one reference catch filter.

[0055] The at least one analysis reservoir and the at least one reference reservoir are preferably fluid reservoirs. The at least one analysis reservoir is in particular configured for receiving at least one fluid comprising at least one antimicrobial compound and / or at least one antimicrobial substance. At least one reference reservoir is in particular configured for receiving at least one reference fluid, wherein the reference fluid is a fluid which is free from antimicrobial compounds and / or antimicrobial substances. The reference fluid preferably corresponds to the fluid comprising at least one antimicrobial compound to be applied to the analysis reservoir. It is for example possible that at least one analysis reservoir and / or at least one reference reservoir is configured to receive at least 5 ml fluid, in particular at least 10 ml more in particular at least 20 ml. It is also conceivable that at least one analysis reservoir and / or at least one reference reservoir is configured to receive at most 100 ml fluid, in particular at most 50 ml, more in particular at most 25 ml. In a preferred embodiment the volume of at least one analysis reservoir and / or at least one reference reservoir is in the range of 50 pl to 0.0005 picolitre, such as 40 pl to 0.0054 picolitre.

[0056] The housing preferably comprises a plurality of analysis reservoirs, and wherein the retaining structure is preferably configured for retaining a plurality of analysis catch filters. In particular, the retaining structure is configured for retaining an equivalent amount of analysis catch filters as the number of analysis reservoirs of the housing. A device comprising a plurality of analysis and a plurality of analysis catch filters is beneficial as it enables to perform a plurality of measurements within the same device. Optionally, it enables to simultaneously perform a plurality of measurements. For example, this embodiment is capable to set different conditions for the different analysis catch filters and / or analysis reservoirs. Therewith, it contributes to a more efficient and effective device.

[0057] It is beneficial if at least one retaining structure is displaceable at least between the filtering configuration and the processing configuration. Optionally, at least one retaining structure and at least one analysis reservoir and / or at least one reference reservoir are mutually displaceable. It is also imaginable that at least one retaining structure is displaceable at least between the filtering configuration and the processing configuration. At least one analysis reservoir and / or at least one reference reservoir could be substantially stationary received in the housing. In yet another possible embodiment, it is also imaginable that at least one retaining structure and at least one analysis reservoir and / or at least one reference reservoir are displaceable. Alternatively, at least one analysis reservoir and / or at least one reference reservoir could be displaceable and at least one retaining structure could be substantially stationary positioned within the housing. It is for example imaginable that at least one retaining structure and / or at least one analysis reservoir and / or at least one reference reservoir is slidable between the filtering configuration and the processing configuration. Optionally, in the processing configuration at least one analysis catch filter retained in the retaining structure at least partially covers the at least one analysis reservoir and / or at least one reference catch filter retained in the retaining structure at least partially covers the at least one reference reservoir. The analysis reservoir and / or the reference reservoir could for example each define at least one fluid opening. It could be possible that at least part of at least one analysis catch filter retained in the retaining structure at least partially, and preferably fully covers, at least one fluid opening of the analysis reservoir at least in the processing configuration and / or that at least part of at least one reference catch filter retained in the retaining structure at least partially, and preferably fully covers, at least one fluid opening of the reference reservoir at least in the processing configuration. Hence, the housing is preferably configured such that at least part of at least one analysis catch filter and / or at least part of at least one reference catch filter retained in the retaining structure at least partially, and preferably fully covers, at least one fluid opening of the analysis reservoir and / or of the reference reservoir, respectively, at least in the processing configuration. It is imaginable that at least one analysis catch filter and / or at least one reference catch filter retained in the retaining structure is positioned at a distance from at least one analysis reservoir and / or at least one reference reservoir, respectively, and in particular at least one opening of at least one analysis reservoir and / or at least one reference reservoir, respectively, at least in the filtering configuration.

[0058] The device could also comprise at least one sealing member configured to couple at least one analysis reservoir and at least one retaining structure in a liquid-proof or liquid-tight manner, preferably at least in the processing configuration, and / or wherein at least one sealing member is configured to couple the at least one reference reservoir and the retaining structure in a liquid-proof or liquid-tight manner, preferably at least in the processing configuration. At least one sealing member may be configured to seal at least part of the analysis reservoir and / or at least part of the reference reservoir, in particular at least one opening of the analysis reservoir and / or reference reservoir, respectively. Optionally, the device comprises at least one first sealing member configured to couple at least one analysis reservoir and at least one retaining structure in a liquid-proof or liquid-tight manner, and at least one second sealing member configured to couple at least one reference reservoir and at least one retaining structure in a liquid-proof or liquid- tight manner. It is for example possible that at least part of at least one sealing member surrounds or encloses at least part of the analysis catch filter retained in the retaining structure and / or that at least one sealing member surrounds or encloses at least part of the reference catch filter retained in the retaining structure. It is possible that at least one sealing member is a releasable sealing member. It is also conceivable that at least one sealing member forms integral part of the housing, in particular of the retaining structure and / or the analysis reservoir and / or reference reservoir.

[0059] It is imaginable that at least one reference reservoir and / or at least one analysis reservoir and / or at least one retaining structure are detachably connected to the housing. Optionally, that at least part of the analysis reservoir and / or at least part of the reference reservoir is detachable with respect to the housing. It is also possible that at least part of retaining structure is detachable with respect to the housing. At least part of the reference reservoir and / or analysis reservoir and / or the retaining structure being detachable is beneficial for cleaning purposes. In case the device is used multiple times, the device need to be fully cleaned prior to a new cycle of use. During use, for example when a method according to the invention is applied, it is highly desired that the device is not contaminated as this could negatively affect the analysis of any pathogenic microorganisms.

[0060] Preferably, at least part of at least one reference reservoir and / or at least part of at least one analysis reservoir comprises a translucent or transparent portion. It is beneficial if the analysis reservoir and / or the reference reservoir comprises at least one translucent and / or transparent portion for enabling visual inspection and / or analysis purposes. It is possible that antimicrobial susceptibility of pathogenic microorganisms is analysed via fluid present in the analysis reservoir and / or reference reservoir. It is in particular interesting if a portion of the analysis reservoir and / or the reference reservoir located at an opposite side of at least a part of the retaining structure, more particular located at an opposite side of the analysis catch filter or reference catch filter, respectively, if retained in the retaining structure, is at least partially translucent and / or transparent. It is for example possible that at least one analysis reservoir and / or at least one reference reservoir comprises a substantially transparent and / or substantially translucent side wall. It is also possible that the analysis reservoir and / or the reference reservoir is formed of a substantially transparent and / or substantially translucent material.

[0061] The housing may comprise at least one application opening for passaging at least one body fluid sample, wherein in the filtering configuration at least one application opening is aligned with at least one analysis catch filter for passaging at least one body fluid sample through the at least one analysis catch filter and / or wherein at least one application opening is aligned with at least one reference catch filter for passaging at least one body fluid sample through the at least one reference catch filter. The housing may be adjustable between a first filtering configuration, wherein at least one application opening is aligned with at least one analysis catch filter retained in the retaining structure and a second filtering configuration, wherein at least one application opening is aligned with at least one reference catch filter retained in the retaining structure. It is imaginable that the housing comprises one application opening for passaging at least one body fluid sample through a respective catch filter. Alternatively, the housing comprises a plurality of application openings. Preferably, each application opening is configured to be aligned with one analysis catch filter or one reference catch filter retained by the retaining structure for passaging at least one body fluid sample through the respective catch filter. At least one application opening could also be referred to as a syringe opening. The at least one syringe opening could be configured for receiving at least part of at least one syringe. It is configured that at least one syringe could be connected to at least one housing in particular via at least one application opening. It is also possible that the device comprises at least one sample applicator for applying at least one body fluid sample to the catch filter at least in the filtering configuration. At least one sample applicator is connected or connectable to at least one application opening.

[0062] The housing may define at least one accommodation space configured to at least partially accommodate at least one coarse filter which is configured for removing at least a fraction of particles from at least one body fluid sample, in particular particles which are larger than pathogenic microorganisms, and preferably wherein the at least one accommodation space is at least partially aligned with at least one analysis catch filter and / or at least one reference catch filter retained by the retaining structure, at least in the filtering configuration. Preferably, the housing may define at least two accommodation spaces each configured for accommodating at least one coarse filter, wherein at least one first accommodation space is at least partially aligned with at least one analysis catch filter and at least one second accommodation space is at least partially aligned with at least one reference catch filter, at least in the filtering configuration. Optionally, at least in the filtering configuration at least one accommodation space is at least partially aligned with the retaining structure configured to retain at least one analysis catch filter and at least one reference catch filter. It is also imaginable that the device, and in particular the housing thereof, comprises at least one secondary retaining structure configured to retain at least part of at least one coarse filter. It is imaginable that the secondary retaining structure is positioned adjacent to, for example substantially parallel to, the (primary) retaining structure such that at least one coarse filter retained in the secondary retaining structure is substantially parallel to at least one analysis catch filter and / or to at least one reference catch filter retained in the (primary) retaining structure. Preferably, for each analysis catch filter and / or for each reference catch filter retained by the (primary) retaining structure at least one coarse filter is provided. Optionally, for each analysis catch filter and / or for each reference catch filter the housing comprises a separate and / or independent accommodation space. The coarse filter and the analysis and / or reference catch filter are preferably at least partially aligned during use. It is imaginable that the coarse filter is provided at an upstream side from the catch filter in respect of an application direction of the body fluid sample to the catch filter. The body fluid sample is preferably first filtered through the coarse filter and thereafter through the catch filter. The body fluid can in fact be filtered substantially simultaneously through at least one coarse filter and at least one catch filter. In a possible embodiment, it is also imaginable that the retaining structure configured to retain at least one catch filter and at least one coarse filter.

[0063] The device, and in particular the housing, may comprise multiple openings. It is for example possible that the housing comprises at least one processing opening for passaging fluid to at least one analysis reservoir and / or to at least one reference reservoir. Preferably, at least one processing opening is at least partially aligned with at least one analysis fluid reservoir in the processing configuration for passaging fluid comprising at least one antimicrobial compound to the at least one analysis reservoir and / or at least one processing opening is at least partially aligned with at least one reference fluid reservoir in the processing configuration for passaging reference fluid to the at least one reference reservoir. It is imaginable that the housing comprises a plurality of processing openings, wherein at least one first processing opening is configured for passaging fluid to the analysis reservoir(s) and at least one second processing opening is configured for passing fluid to the reference reservoir(s). Optionally, the housing comprises an equivalent amount of processing openings as the total number of analysis reservoir(s) and reference reservoir(s) of the housing. This contributes to minimizing contamination from fluids applied to the different analysis reservoir(s) and / or reference reservoir(s). The device may further comprise at least one fluid applicator for applying at least one fluid to at least one analysis reservoir or to at least one reference reservoir in the processing configuration. Preferably, the device comprises separate and / or independent fluid applicators for applying a fluid to the at least one analysis reservoir and for applying a (reference) fluid to the at least one reference reservoir. The device can also be configured for co-action with at least one fluid applicator, which is in particular configured for applying fluid to the at least one analysis reservoir and / or to the at least one reference reservoir in the processing configuration. It is imaginable that at least one fluid applicator comprises a solution comprising SERS-active nanoparticles to be filtered through at least one analysis catch filter and / or at least one reference catch filter retained in the retaining structure such that at least part of the at least one analysis catch filter and / or the at least one reference catch filter, respectively, will be coated with SERS-active nanoparticles thereby forming a SERS substrate. Optionally, at least one fluid applicator which is configured for applying a fluid to the at least one reference reservoir comprises a fluid configured to apply a stress stimulus to at least part of at least one reference catch filter retained in the at least one retaining structure, in particular to the captured fraction of pathogenic microorganisms from a body fluid sample if present in the body fluid sample. As a response to the applied stress stimulus, at least a fraction of the captured pathogenic microorganisms secretes and / or excretes stress responsive biomolecules. Secreted and / or excreted stress responsive biomolecules may at least partially deviate from secreted and / or excreted antimicrobial responsive biomolecules. Hence, it is possible to compare at least one reference characteristic related to stress responsive biomolecules with at least one susceptibility characteristic related to antimicrobial responsive biomolecules for determining susceptibility to the applied antimicrobial compound. At least one fluid applicator may be connectable to at least one processing opening for passaging fluid from the fluid applicator to at least one analysis reservoir and / or at least one reference reservoir in the processing configuration. Preferably, at least two separate and / or independent fluid applicators are connectable to at least one processing opening, wherein a first fluid applicator is configured for passaging reference fluid to a reference reservoir and / or a second fluid applicator is configured for passaging fluid comprising at least one antimicrobial compound to the analysis reservoir in the processing configuration. In a possible embodiment, the retaining structure comprises at least two inlets, wherein a first inlet is at least partially aligned with and / or joined to at least one reference reservoir in the processing configuration for passaging reference fluid to the reference reservoir and wherein a second inlet is at least partially aligned with and / or joined to at least one analysis reservoir in the processing configuration for passaging fluid comprising at least one antimicrobial compound to the analysis reservoir. It is conceivable that at least one processing opening and the first inlet together form a fluid conduct in the processing configuration for guiding reference fluid to the reference reservoir and / or that at least one processing opening and the second inlet together form a fluid conduct in the processing configuration for guiding fluid comprising at least one antimicrobial compound to the analysis reservoir.

[0064] The device may further comprise at least one absorbing body for absorbing a fraction of fluid comprising at least one antimicrobial compound and / or for absorbing a fraction of reference fluid. This is in particular useful when at least one of beforementioned fluids is present in excess. At least one absorbing body may comprise at least one fluid absorbing material. This can for example be a sponge or a sponge-like material. It is preferred that at least one absorbing body is provided adjacent to at least part of the analysis reservoir and / or to at least part of the reference reservoir and / or adjacent to at least one of the (fluid) inlets. At least one absorbing body is for example provided at an end side of the housing.

[0065] The invention further relates to the use of (at least part of) a device according to present invention, in particular in a Raman Spectrometer for analysing antimicrobial compound susceptibility of pathogenic microorganisms in body fluid samples.

[0066] The invention will be further elucidated by means of the following non-limitative clauses. 1 . Method for analysing antimicrobial compound susceptibility of pathogenic microorganisms in body fluid samples, comprising the steps of:

[0067] A) providing at least one body fluid sample,

[0068] B) filtering the at least one body fluid sample through at least one catch filter which is configured for capturing at least a fraction of pathogenic microorganisms from the at least one body fluid sample if present in the body fluid sample,

[0069] C) applying at least one fluid comprising at least one antimicrobial compound to at least part of the at least one catch filter, in particular to the fraction of pathogenic microorganisms, such that at least a fraction of the captured pathogenic microorganisms extracellularly secretes antimicrobial responsive biomolecules,

[0070] D) analysing at least part of the extracellularly secreted antimicrobial responsive biomolecules and determining at least one susceptibility characteristic of the analysed extracellularly secreted antimicrobial responsive biomolecules, and

[0071] E) comparing at least one determined susceptibility characteristic with at least one reference characteristic corresponding to the at least one determined susceptibility characteristic thereby determining the susceptibility of at least part of the captured pathogenic microorganisms to the at least one antimicrobial compound.

[0072] 2. Method according to clause 1 , wherein at least one susceptibility characteristic relates to the amount of antimicrobial responsive biomolecules extracellularly secreted by a fraction of the captured pathogenic microorganisms.

[0073] 3. Method according to clause 1 or clause 2, wherein at least one susceptibility characteristic relates to the type of antimicrobial responsive biomolecules extracellularly secreted by a fraction of the captured pathogenic microorganisms.

[0074] 4. Method according to any of the clauses 2-3, wherein at least one susceptibility characteristic relates to a ratio of the amount and / or the type antimicrobial responsive biomolecules extracellularly secreted by a fraction of the captured pathogenic microorganisms relative to non-antimicrobial responsive biomolecules secreted by a fraction of the captured pathogenic microorganisms. 5. Method according to any of the preceding clauses, wherein at least one susceptibility characteristic relates to the composition of antimicrobial responsive biomolecules extracellularly secreted by a fraction of the captured pathogenic microorganisms.

[0075] 6. Method according to any of the preceding clauses, wherein in step D) at least one susceptibility profile is determined which is formed by a combination of a plurality of susceptibility characteristics, and wherein in step E) at least one susceptibility profile is compared with at least one reference profile which is formed by a combination of reference characteristics.

[0076] 7. Method according to any of the preceding clauses, comprising a step F) of identifying at least a fraction of the extracellularly secreted antimicrobial responsive biomolecules and determining the type of antimicrobial responsive biomolecules extracellularly secreted by at least a fraction of the captured pathogenic microorganisms and / or determining the composition of antimicrobial responsive biomolecules extracellularly secreted by at least a fraction of the captured pathogenic microorganisms, wherein step F) is performed after step C).

[0077] 8. Method according to any of the preceding clauses, comprising a step G) of analysing at least one fluid comprising at least one antimicrobial compound to be applied to and / or applied to at least part of the at least one catch filter and determining at least one reference characteristic of said analysed fluid.

[0078] 9. Method according to any of the preceding clauses, comprising a step H) of providing at least one reference fluid which corresponds to the fluid to be applied or applied in step C), wherein the reference fluid is free from antimicrobial compound.

[0079] 10. Method according to clause 9, comprising a step of analysing said reference fluid and determining at least one reference characteristic corresponding to the reference fluid.

[0080] 11 . Method according to any of the preceding clauses, comprising a step I) of analysing the at least one catch filter and determining at least one reference characteristic of said at least one catch filter, wherein step I) is performed prior to step C).

[0081] 12. Method according to any of the preceding clauses, wherein step D) is repeated at least at two different time points.

[0082] 13. Method according to any of the preceding clauses, comprising a step J) of dividing at least one body fluid sample in at least two separate sample parts, and wherein at least steps B) and C) are performed separately for at least two separate sample parts.

[0083] 14. Method according to clause 13, wherein a concentration of at least one antimicrobial compound in the fluid applied in step C) is different for the separately performed steps C) for at least two separate sample parts.

[0084] 15. Method according to clause 13 or clause 14, wherein the type of antimicrobial compound in the fluid applied in step C) is different for the separately performed steps C) for at least two separate sample parts.

[0085] 16. Method according to any of the clauses 9-10 and any of the clauses 13-15, wherein during at least one separately performed step C) at least one reference fluid is applied instead of at least one fluid comprising at least one antimicrobial compound, thereby forming a reference sample part.

[0086] 17. Method according to clause 16, comprising a step of analysing the reference sample part and determining at least one reference characteristic of the analysed reference sample part.

[0087] 18. Method according to any of the preceding clauses, wherein step D) is performed by means of Raman Spectroscopy, in particular Surface-Enhanced Raman Spectroscopy (SERS), and / or biochemical analysis and / or electrical analysis.

[0088] 19. Method according to any of the preceding clauses, comprising step K) of concentrating at least part of at least one fluid in which the captured pathogenic microorganisms and / or the extracellularly secreted antimicrobial responsive biomolecules are suspended, such that the concentration of captured pathogenic microorganisms and / or the concentration of extracellularly secreted antimicrobial responsive biomolecules is increased.

[0089] 20. Method according to clause 19, wherein step K) is performed by heating.

[0090] 21 . Method according to any of the preceding clauses, comprising a step L) of filtering at least one body fluid sample through at least one coarse filter which is configured for removing at least a fraction of particles from the body fluid sample, in particular particles which are larger than pathogenic microorganisms.

[0091] 22. Method according to any of the preceding clauses, wherein at least a part of the catch filter is coated with nanoparticles, in particular SERS-active nanoparticles to form a SERS substrate.

[0092] 23. Method according to any of the preceding clauses, comprising a step M) of filtering at least one solution comprising nanoparticles, in particular SERS-active nanoparticles through the catch filter such that at least part of the catch filter will be coated with said nanoparticles.

[0093] 24. Device for processing at least one body fluid sample for analysing antimicrobial compound susceptibility of pathogenic microorganisms in at least one body fluid sample, comprising:

[0094] - at least one housing, comprising: o at least one retaining structure for separately and / or independently retaining at least one analysis catch filter and at least one reference catch filter, o at least one analysis reservoir configured for receiving at least one fluid comprising at least one antimicrobial compound, and o at least one reference reservoir configured for receiving at least one reference fluid, wherein the analysis reservoir and the reference reservoir are located at a distance from each other, - optionally, at least one analysis catch filter and at least one reference catch filter configured to capture at least a fraction of pathogenic microorganisms from a body fluid sample, wherein at least one housing is a modular housing which is adjustable between:

[0095] - a filtering configuration, wherein at least one body fluid sample can be filtered through at least one analysis catch filter retained in at least one retaining structure and wherein at least one body fluid sample can be filtered through at least one reference catch filter retained in at least one retaining structure; and

[0096] - a processing configuration, wherein at least one retaining structure is positioned adjacent to at least part of at least one analysis reservoir such that fluid comprising at least one antimicrobial compound received in at least one analysis reservoir can get into contact with at least part of at least one analysis catch filter retained in the at least one retaining structure, and wherein at least one retaining structure is positioned adjacent to at least part of at least one reference reservoir such that at least one reference fluid received in at least one retaining reservoir can get into contact with at least part of at least one reference catch filter retained in the at least one retaining structure.

[0097] 25. Device according to clause 24, wherein the housing comprises a plurality of analysis reservoirs, and wherein the retaining structure is preferably configured for retaining a plurality of analysis catch filters.

[0098] 26. Device according to clause 24 or clause 25, wherein at least one retaining structure is displaceable at least between the filtering configuration and the processing configuration.

[0099] 27. Device according to any of the clauses 24 to 26, wherein in the processing configuration at least one analysis catch filter retained in the retaining structure at least partially covers the at least one analysis reservoir and / or wherein at least one reference catch filter retained in the retaining structure at least partially covers the at least one reference reservoir. 28. Device according to any of the clauses 24 to 27, comprising at least one sealing member configured to couple at least one analysis reservoir and at least one retaining structure in a liquid-proof or liquid-tight manner, preferably at least in the processing configuration and / or wherein at least one sealing member is configured to couple the at least one reference reservoir and the retaining structure in a liquid-proof or liquid-tight manner, preferably at least in the processing configuration.

[0100] 29. Device according to any of the clauses 24 to 28, wherein at least one reference reservoir and / or at least one analysis reservoir and / or at least one retaining structure are detachably connected to the housing.

[0101] 30. Device according to any of the clauses 24 to 29, wherein at least part of at least one reference reservoir and / or at least part of at least one analysis reservoir comprises a translucent or transparent portion.

[0102] 31 . Device according to any of the clauses 24 to 30, wherein the housing comprises at least one application opening for passaging at least one body fluid sample, wherein in the filtering configuration at least one application opening is aligned with at least one analysis catch filter for passaging at least one body fluid sample through the at least one analysis catch filter and / or wherein at least one application opening is aligned with at least one reference catch filter for passaging at least one body fluid sample through the at least one reference catch filter.

[0103] 32. Device according to any of the clauses 24 to 31 , comprising at least one sample applicator for applying at least one body fluid sample to at least one reference catch filter and / or to at least one analysis catch filter at least in the filtering configuration.

[0104] 33. Device according to clause 31 and clause 32, wherein the sample applicator is connected or connectable to at least one application opening.

[0105] 34. Device according to any of the clauses 24 to 33, wherein the housing defines at least one accommodation space configured to at least partially accommodate at least one coarse filter which is configured for removing at least a fraction of particles from at least one body fluid sample, in particular particles which are larger than pathogenic microorganisms, and preferably wherein the at least one accommodation space is at least partially aligned with at least one analysis catch filter and / or at least one reference catch filter retained by the retaining structure, at least in the filtering configuration.

[0106] 35. Device according to any of the clauses 24 to 34, wherein the housing comprises at least one processing opening for passaging fluid to at least one analysis reservoir and / or to at least one reference reservoir, wherein at least one processing opening is at least partially aligned with at least one analysis reservoir in the processing configuration for passaging fluid comprising at least one antimicrobial compound to the at least one analysis reservoir and / or wherein at least one processing opening is at least partially aligned with at least one reference fluid reservoir in the processing configuration for passaging reference fluid to the at least one reference reservoir.

[0107] 36. Device according to any of the clauses 24 to 35, comprising at least one fluid applicator for applying at least one fluid to at least one analysis reservoir or to at least one reference reservoir in the processing configuration.

[0108] 37. Device according to clause 36, wherein at least one fluid applicator comprises a solution comprising SERS-active nanoparticles to be filtered through at least one analysis catch filter and / or at least one reference catch filter retained in the retaining structure such that at least part of the at least one analysis catch filter and / or the at least one reference catch filter, respectively, will be coated with SERS-active nanoparticles thereby forming a SERS substrate.

[0109] 38. Device according to clause 35 and any of the clauses 36-37, wherein at least one fluid applicator is connectable to at least one processing opening for passaging fluid from the fluid applicator to at least one analysis reservoir and / or at least one reference reservoir in the processing configuration.

[0110] 39. Device according to any of the clauses 24 to 38, wherein the retaining structure comprises at least two inlets, wherein a first inlet is at least partially aligned with at least one reference reservoir in the processing configuration for passaging reference fluid to at least one reference reservoir and wherein a second inlet is at least partially aligned with at least one analysis reservoir in the processing configuration for passaging fluid comprising at least one antimicrobial compound to at least one analysis reservoir.

[0111] 40. Device according to clause 35 and clause 39, wherein at least one processing opening and the first inlet together form a fluid conduct in the processing configuration for guiding reference fluid to the reference reservoir and / or wherein at least one processing opening and the second inlet together form a fluid conduct in the processing configuration for guiding fluid comprising at least one antimicrobial compound to the analysis reservoir.

[0112] 41 . Device according to any of the clauses 24 to 40, comprising at least one absorbing body for absorbing a fraction of fluid comprising at least one antimicrobial compound and / or for absorbing a fraction of reference fluid.

[0113] 42. Device according to clause 41 , wherein at least absorbing body is provided adjacent to the analysis reservoir and / or to the reference reservoir.

[0114] 43. Use of the device according to any of the clauses 24-42 in a Raman Spectrometer for analysing antimicrobial compound susceptibility of pathogenic microorganisms in body fluid samples.

[0115] The invention will be further elucidated by several examples and with reference to the appended figures, wherein:

[0116] - Figure 1 schematically shows a method for therapeutical compound susceptibility of analytes in fluid samples according to the present invention,

[0117] - Figure 2 schematically shows a method for antimicrobial compound susceptibility of pathogenic microorganisms in body fluid samples according to the present invention,

[0118] - Figures 3a-3b schematically show a device according to the present invention, and

[0119] - Figure 4 schematically shows a cross-sectional view of a device in a filtering configuration according to the present invention. Within these figures, similar reference numbers correspond to similar or equivalent elements or features.

[0120] Figure 1 schematically shows a method for analysing therapeutical compound susceptibility of analytes Ai, A2in at least one fluid sample S according to the present invention. In step A) the fluid sample S is provided. The fluid sample S preferably is a body fluid sample, such as blood. In step B) at least a fraction of at least one analyte Ai, A2from the at least one fluid sample S is isolated. In the shown embodiment, the analytes Ai, A2are isolated by filtering the (body) fluid sample S through at least one catch filter 1 . The catch filter 1 is configured for capturing at least a fraction of the analytes Ai, A2from the fluid sample S. Hence, the analytes Ai, A2are captured on and / or within the catch filter 1 . The analytes Ai, A2are preferably pathogenic microorganisms, such as bacteria, fungi and / or parasites. In step C) at least one fluid F comprising at least one therapeutic compound, in particular an antimicrobial compound, is applied to at least part of the isolated analytes Ai, A2. The isolated analytes Ai, A2extracellularly secrete and / or excrete therapeutic responsive biomolecules 2. Preferably, the fluid F comprises at least one antimicrobial compound such that the isolated analytes Ai, A2extracellularly secrete and / or excrete antimicrobial responsive biomolecules 2. Optionally, the method comprises a step K) of concentrating at least part of at least one fluid F in which the isolated analytes Ai, A2and / or the extracellularly secreted and / or excreted therapeutic responsive biomolecules 2 are suspended, such that the concentration of the isolated analytes Ai, A2and / or the concentration of the extracellularly secreted and / or excreted therapeutic responsive biomolecules is increased. The step K) may for example be performed by heating, in particular by evaporating at least a fraction of the supernatant and / or fluid F of the isolated analytes Ai, A2and therein suspended extracellularly secreted and / or excreted therapeutic responsive biomolecules 2. In step D) at least part of the extracellularly excreted and / or secreted therapeutic responsive biomolecules 2 are analysed using an analyser 3. It is imaginable that the analyser 3 is an imaging modality. Optionally, step D) is performed by means of Raman spectroscopy, SERS and / or biochemical analysis. In addition to the shown step D), the method may comprise a step F) of identifying at least a fraction of the extracellularly secreted and / or excreted therapeutic responsive biomolecules 2. This identification step may be performed using the same analyser 3 or imaging modality. Based on the analysed extracellularly excreted and / or secreted therapeutic responsive biomolecules 2 at least one susceptibility characteristic 4 is determined. The susceptibility characteristic 4 may for example relate to the amount of therapeutic responsive biomolecules 2 and / or relate to the type of therapeutic responsive biomolecules 2 and / or relate to the composition of therapeutic responsive biomolecules 2. Optionally, in step D) a susceptibility profile is determined which is formed by a combination of a plurality of susceptibility characteristics. In step E) the determined susceptibility characteristic(s) is / are compared with at least one reference characteristic 6 corresponding to the at least one determined susceptibility characteristic 4. The reference characteristic 6 may for example be derived or obtained from a database 5. The database 5 may comprise different types of reference characteristics, for example reference characteristics corresponding to the amount of therapeutic responsive biomolecules and / or the type of therapeutic responsive biomolecules and / or the composition of therapeutic responsive biomolecules expected to be extracellularly secreted and / or excreted per type of analyte. Optionally, the database 5 comprises a reference profile formed by a combination of a plurality of reference characteristics. In step E), the degree of similarity between the reference characteristic 6 and the determined susceptibility characteristic 4 may be determined, which preferably correlates to the susceptibility and / or degree of resistance of the isolated analytes Ai, A2to the applied therapeutic compound. Alternatively, the degree of similarity between the reference characteristic 6 and the determined susceptibility characteristic 4 correlates to the effectiveness of the therapeutic compound to the isolated analytes A1 , A2.

[0121] Figure 2 schematically shows a method for antimicrobial compound susceptibility of pathogenic microorganisms A1 , A2 in a body fluid sample S according to the present invention. In step J) the in step A) provided body fluid sample S is divided into two separate sample parts S1 , S2. It is imaginable that the body fluid sample S is divided into more than two separate sample parts. Step B) is performed separately and / or independently for the two separate sample parts S1 , S2. Both of the shown separately and / or independently performed steps B) use a separate and / or independent catch filter 1 a, 1 b, wherein the catch filters 1 a, 1 b are configured to capture pathogenic microorganisms A1 , A2 from the thereto applied body fluid sample S. For a first sample part S1 of the shown embodiment, the following method steps are performed as shown on the left side of the figure. In a first step B), the first sample part S1 is filtered through a first catch filter 1a. The first catch filter 1a is configured to capture pathogenic microorganisms A1 , A2 from the first sample part S1 . In a step C) at least one fluid F comprising at least one antimicrobial compound is applied to the first catch filter 1a. In the shown embodiment, the fluid F is applied after step B). Here, the fluid F is also, directly or indirectly, applied to the, by the first catch filter 1a captured, pathogenic microorganisms A1 , A2. It is imaginable that the sequence of the shown method steps B) and C) is different. For example, steps B) and C) could be performed simultaneously. At least a fraction of the captured pathogenic microorganisms A1 , A2 extracellularly secrete and / or excrete antimicrobial responsive biomolecules 2a-2d as a response to the applied fluid F comprising at least one antimicrobial compound. It is imaginable that the captured pathogenic microorganisms A1 , A2 extracellularly secrete and / or excrete different types of antimicrobial responsive biomolecules 2a-2d. In step D), which is in particular performed after steps A) to C), at least a part of the by the of the first sample S1 captured pathogenic microorganisms A1 , A2 extracellularly secreted and / or excreted antimicrobial responsive biomolecules 2a-2d is analysed by an analyser 3. From these analysed extracellularly secreted and / or excreted antimicrobial responsive biomolecules 2a-2d at least one susceptibility characteristic 14 is determined.

[0122] For the second sample part S2 of the shown embodiment, the following method steps are performed as shown on the right side of the figure. In a second step B) a second sample part S2 is filtered through a second catch filter 1 b. The first catch filter 1a and the second catch filter 1 b are separate and / or independent catch filters. The second catch filter 1 b is configured to capture pathogenic microorganisms A1 , A2 from the second sample part S2. The first catch filter 1a and the second catch filter 1 b preferably have the same, in particular identical, properties, like pore size and / or material properties. In a step C’) a reference fluid Fr is applied to the second catch filter 1 b. The reference fluid Fr applied in step C’) is provided in step H). The reference fluid Fr is a fluid which corresponds to the fluid F as applied in step C), but differs therefrom in that the reference fluid Fr is free from antimicrobial compound(s). As the reference fluid Fr is free from antimicrobial compounds, the captured pathogenic microorganisms A1 , A2 nearly, in particular do not, extracellularly secrete and / or excrete antimicrobial responsive biomolecules. In the shown embodiment, the reference fluid Fr is applied after step B). It is imaginable that the sequence of the shown method steps B) and C’) is different. For example, steps B) and C’) could be performed simultaneously. In a step D’) at least part of the supernatant of the from the second sample part S2 captured pathogenic microorganisms, and / or the captured pathogenic microorganisms A1 , A2 and / or non-antimicrobial responsive biomolecules are analysed by an analyser 3. Thereof, at least one reference characteristic 16 is determined. The analyser 3, and in particular the settings thereof, are preferably the same for step D) and step D'). This step D’) may also be referred to as a baseline measurement or a background (signal) measurement.

[0123] In step E) the determined susceptibility characteristic 14 is compared with the at least one determined reference characteristic 16, wherein the determined reference characteristic 16 corresponds to the determined susceptibility characteristic 14. This in particular means that the determined susceptibility characteristic 14 and the determined reference characteristic 16 at least partially relate to the same parameter or feature. For example, the determined susceptibility characteristic 14 may relate to the amount of different types of antimicrobial responsive biomolecules 2a-2d secreted and / or excreted by the captured pathogenic microorganisms A1 , A2. In that case, the determined reference characteristic 16 also relates to the amount of the same different types of (non-antimicrobial responsive) biomolecules, which may be defined as the remaining biomolecules secreted by the captured pathogenic microorganisms which do not correspond to an antimicrobial compound, secreted and / or excreted by the captured pathogenic microorganisms A1 , A2. It is expected that the pathogenic microorganisms A1 , A2 of the second sample part S2, which are not exposed to an antimicrobial compound, extracellularly secrete and / or excrete a limited amount of, in particular zero, antimicrobial responsive biomolecules. Comparing this amount with the amount of antimicrobial responsive biomolecules extracellularly secreted and / or excreted by the pathogenic microorganisms of the first sample part S1 , which are exposed to at least one antimicrobial compound, allows to determine the susceptibility of at least part of the captured pathogenic microorganisms A1 , A2 of the body fluid sample S to the at least one antimicrobial compound. In particular, the degree of similarity between the reference characteristic 16 and the determined susceptibility characteristic 14 preferably correlates to the susceptibility and / or degree of resistance of the pathogenic microorganisms Ai, A2to the at least one antimicrobial compound.

[0124] Figures 3a-3b schematically show a device 100 for processing at least one body fluid sample S for analysing antimicrobial compound susceptibility of pathogenic microorganisms in the at least one body fluid sample S according to the present invention. The device 100 can be used in the method according to the present invention, preferably at least in steps B) and C) of the method. The device 100 comprises a housing 101 comprising at least one retaining structure 102. The retaining structure 102 of the shown embodiment comprises a reference catch filter 103 and three analysis catch filters 104. The retaining structure 102 is configured for separately and / or independently retaining said catch filters 103, 104. This particularly means that the catch filters 103, 104 are provided at a distance from each other. Hence, the shown reference catch filter 103 and the analysis catch filters 104 are distinct and separate catch filters. Each of the catch filters 103, 104 is configured to capture at least a fraction of pathogenic microorganisms from a body fluid sample S if present in the applied body fluid sample S. The housing 101 further comprises at least one reference reservoir 105 configured for receiving at least one reference fluid Fr and at least one analysis reservoir 106, here three analysis reservoirs 106, for receiving at least one fluid F1 -F3 comprising at least one antimicrobial compound. The reference reservoir 105 preferably is a separate and / or independent reservoir from the analysis reservoirs 106. Preferably, the different analysis reservoirs 106 are separate and / or independent analysis reservoirs 106. This particularly means that the reference reservoir 105 and the three analysis reservoirs 106 are distinct reservoirs. The reference reservoir 105 and the three analysis reservoirs 106 are provided at a distance from each other. The device 100, in particular the housing 101 , is adjustable between a filtering configuration and a processing configuration. Figure 3a shows the device 100 in the filtering configuration and figure 3b shows a possible embodiment of the housing 101 , or the device 100, in the processing configuration.

[0125] Figure 3a schematically shows the housing 101 , or the device 100, in the filtering configuration, wherein the housing 101 is positioned such that at least one body fluid sample S can be filtered through at least one analysis catch filter 104 retained the retaining structure 102 and / or such that at least one body fluid sample S can be filtered through at least one reference catch filter 103 retained the retaining structure 102. In particular, in the filtering configuration the reference reservoir 105 and the analysis reservoirs 106 are not aligned with any of the catch filters 103, 104. The housing 101 may be adjusted between the filtering configuration and the processing configuration (see figure 3b) by displacing the housing 101 and the retaining structure 102 relative to each other. This may for example be done by displacing or sliding the retaining structure 102 along the longitudinal direction of the housing 101. Preferably, at least such that at least a part of the retaining structure 102 and / or at least one reference catch filter 103 retained in the retaining structure 102 is at least partially aligned with an application opening 107 of the reference reservoir 105. Additionally or alternatively, preferably at least such that at least a part of the retaining structure 102 and / or at least one analysis catch filter 104 retained in the retaining structure 102 is at least partially aligned with an application opening 108 of an analysis reservoir 106. More preferably, such that the reference catch filter 103 is at least partially aligned with the application opening 107 of the reference reservoir 105 and such that each analysis catch filter 104 is at least partially aligned with an application opening 108 of the analysis reservoirs 106.

[0126] Figure 3b schematically shows the housing 101 , or the device 100, in the processing configuration, wherein the retaining structure 102 is positioned such that the reference catch filter 103 is positioned adjacent to the reference reservoir 107. The retaining structure 102 is positioned such that the reference fluid Fr applied to the reference reservoir 105 can get into contact with at least part of the reference catch filter 103 retained in the at least one retaining structure 102. Further in the processing configuration, the retaining structure 102 is positioned such that each of the analysis catch filters 104 retained in the retaining structure 102 is positioned adjacent to an analysis reservoir 106. Providing a plurality of analysis catch filters 104 allows to create a plurality of different analysis environments. This may for example allow to determine susceptibility of captured pathogenic microorganisms of the applied body fluid sample for different concentrations of antimicrobial compound of the applied fluid F1-F3.

[0127] Figure 4 schematically shows a cross-sectional view of a device 200 in a filtering configuration for processing at least one body fluid sample S for analysing antimicrobial compound susceptibility of pathogenic microorganisms in the at least one body fluid sample S according to the present invention. The device 200 comprises a housing 201 which comprises a retaining structure 202 for retaining at least one reference catch filter 203 and at least one analysis catch filter 204. The catch filters 203, 204 are configured to capture at least a fraction of pathogenic microorganisms from the body fluid sample S if present. In the shown embodiment, the body fluid sample S is filtered through the analysis catch filter 204 retained in the retaining structure 202. The reference catch filter 203 retained in the retaining structure 202 at a distance from the analysis catch filter 204. The reference catch filter 203 and the analysis catch filter 204 of the shown device 200 are both located in the housing 201 . In the shown embodiment, the body fluid sample S is not (yet) filtered through the reference catch filter 203. As the housing 201 , in particular the retaining structure 202, are displaceable relative to each other, the reference catch filter 203 can be displaced to a following filtering configuration wherein a body fluid sample S can be filtered through the reference catch filter 203 retained in the retaining structure 202. A portion of the shown retaining structure 202 and / or a portion of the housing 201 comprises a first sealing member 217 to liquid-tight or liquid-proof enclose the analysis catch filter 204 retained in the retaining structure 202. Therewith, leakage of body fluid sample S into the remaining of the housing 201 is limited or prevented. It is imaginable that the retaining structure 202 comprises a first sealing member 217 which encloses the reference catch filter 203, in particular at least when the reference catch filter 203 is positioned in filtering configuration. The body fluid sample S may be applied by means of a sample applicator 209. In the shown embodiment, the sample applicator 209 is connected to the housing 201. The housing 201 may comprise an application opening 210 for passaging a body fluid sample S. The application opening 210 is preferably at least partially aligned with the respective catch filter 203, 204 positioned in the filtering configuration, in particular such that the body fluid sample S can be filtered through the respective catch filter 203, 204. In the shown embodiment, the application opening is aligned with the analysis filter 204. In the shown embodiment, the housing 201 comprises two application openings 210. The application openings 210 may together form a fluid conduct for guiding the body fluid sample S into and away from the housing 201 , in particular such that the body fluid sample S is filtered through the catch filter which is aligned with the application opening 210, here the analysis catch filter 204. In the filtering configuration, the application openings 210 are preferably at least partially aligned with at least a part of at least one of the reference catch filter 203 and the analysis catch filter 204. In the filtering configuration, the sample applicator 209 is preferably at least partially aligned with at least a part of at least one of the reference catch filter 203 and the analysis catch filter 204, such that the body fluid sample S can be filtered through the respective catch filter 203, 204. Here, the sample applicator 209 is aligned with at least part of the analysis catch filter 204. The sample applicator 209 may be an aspiration device, such as a syringe. The shown sample applicator 209 comprises a receiving section 209a for receiving the filtrate of the filtered body fluid sample S and an aspiration tube 209b for passaging body fluid sample S to the housing 201 , in particular to the therewith aligned catch filter 203, 204, here the analysis catch filter 204. In the shown embodiment, the aspiration tube 209b is connected to the housing 201 at an opposite side of the receiving section 209a the aspiration tube 209b. The receiving section 209a and the aspiration tube 209b are connected to the housing 201 via application openings 210. The housing 201 and / or the sample applicator 209 may further comprise a coarse filter 218 for removing at least a fraction of particles from the body fluid sample S, in particular particles which are larger than pathogenic microorganisms. The coarse filter 218 and at least one of the reference catch filter 203 and the analysis catch filter 204 are preferably at least partially aligned in the filtering configuration. As in the shown embodiment the analysis catch filter 204 is in the filtering configuration, the analysis catch filter 204 and the coarse filter 218 are at least partially aligned. The body fluid sample S is preferably first filtered through the coarse filter 218 and thereafter through a catch filter 203, 204. In the shown embodiment, at least a part of the coarse filter 218 is connected to an application opening 210 of the housing 201. In the shown embodiment, the housing 201 comprises an accommodation space 219 for accommodating a coarse filter 218. In particular at least one side wall 220 of the accommodation space 219 comprises an application opening 210. More in particular, two opposite side walls 220 of the accommodation space 210 comprise an application opening 210. The application openings 210 at the opposite side walls 220 of the accommodation space 219 are at least partially aligned, such that body fluid sample S can be passed through the coarse filter 218 in the accommodation space 219.

[0128] The housing 201 further comprises a reference reservoir 205 for receiving at least one reference fluid Fr and an analysis reservoir 206 for receiving at least one fluid F comprising at least one antimicrobial compound. The housing 201 is adjustable from the shown filtering configuration to a processing configuration. The retaining structure 202 is moveable, in particular slideable, at least between the filtering configuration and the processing configuration. In the processing configuration (not shown) the reference catch filter 203 is provided in the reference reservoir 205 and / or the analysis catch filter 204 is provided in the analysis reservoir 204. The reference reservoir 205 and the analysis reservoir 204 of the shown embodiment are enclosed by the retaining structure 202 and a covering element 221. It is imaginable that the housing 201 comprises a separate and / or independent covering element 221 for each reference reservoir 205 and / or for each analysis reservoir 204. The covering element 221 may comprise a transparent or translucent cover 222. In particular, the covering element 221 comprises a separate and / or independent cover 222 for each reference reservoir 205 and / or for each analysis reservoir 204. Hence, the shown embodiment comprises two separate covers 222. One for the reference reservoir 205 and one for the analysis reservoir 206. The covering element 221 and / or at least a part of the housing 201 and / or at least a part of the retaining structure 202 comprise a second sealing member 223 configured to liquid-proof or liquid-tight enclose the reference reservoir 205 and / or the analysis reservoir 206. The shown retaining structure 202 comprises two inlets 224a for passaging fluid, in particular when the device 1 is positioned in the processing configuration. A first inlet 224a is provided near, or substantially adjacent to, the reference catch filter 203 and a second inlet 224a is provided near, or substantially adjacent to, the analysis catch filter 204. The housing 201 may comprise at least one processing opening 224b for passaging fluid F, in particular when the device 1 is positioned in the processing configuration. The shown housing 201 comprises two processing openings 224b. At least in the processing configuration, a first processing opening 224b can be fluidly connected to the reference reservoir 205 and a second processing opening 224b can be fluidly connected to the analysis reservoir 206. In the processing configuration, the retaining structure 202 and the housing 201 are preferably positioned such that the first inlet 224a of the retaining structure 202 and the first processing opening 224b of the housing 201 are at least partially aligned for allowing reference fluid Fr to passage to the reference reservoir 205 and / or such that the second inlet 224a of the retaining structure 202 and the second processing opening 224b of the housing 201 are at least partially aligned for allowing fluid F to passage to the analysing reservoir 206. Therewith, the inlets 224a and the processing openings 224b form a fluid conducts for passaging fluid F to the reference reservoir 205 or to the analysis reservoir 206. In the shown embodiment, a first fluid applicator 225a comprising a reference fluid Fr is connected to the first passage opening 224b of the housing 201 and a second fluid applicator 225b comprising a fluid F comprising at least one antimicrobial compound is connected to the second passage opening 224b of the housing 201. The device 200, and in particular the housing 201 , furthermore comprises an absorbing body 226 configured to absorb a fraction of fluid F and / or reference fluid Fr and / or body fluid sample S, in particular when present in excess. The absorbing body 226 of the shown device 200 is provided at an end side of the housing 201 . In the shown embodiment, the absorbing body 226 is provided next to or near the second fluid applicator 225b.

[0129] It will be clear that the invention is not limited to the exemplary embodiments which are illustrated and described here, but that countless variants are possible within the framework of the attached claims, which will be obvious to the person skilled in the art. In this case, it is conceivable for different inventive concepts and / or technical measures of the above-described variant embodiments to be completely or partly combined without departing from the inventive idea described in the attached claims.

[0130] The verb 'comprise' and its conjugations as used in this patent document are understood to mean not only 'comprise', but to also include the expressions 'contain', 'substantially contain', 'formed by' and conjugations thereof.

Claims

Claims1 . Method for analysing antimicrobial compound susceptibility of pathogenic microorganisms in body fluid samples, comprising the steps of:A) providing at least one body fluid sample,B) filtering the at least one body fluid sample through at least one catch filter which is configured for capturing at least a fraction of pathogenic microorganisms from the at least one body fluid sample if present in the body fluid sample,C) applying at least one fluid comprising at least one antimicrobial compound to at least part of the at least one catch filter, in particular to the fraction of pathogenic microorganisms, such that at least a fraction of the captured pathogenic microorganisms extracellularly secretes antimicrobial responsive biomolecules,D) analysing at least part of the extracellularly secreted antimicrobial responsive biomolecules and determining at least one susceptibility characteristic of the analysed extracellularly secreted antimicrobial responsive biomolecules, andE) comparing at least one determined susceptibility characteristic with at least one reference characteristic corresponding to the at least one determined susceptibility characteristic thereby determining the susceptibility of at least part of the captured pathogenic microorganisms to the at least one antimicrobial compound, wherein the method steps are performed within 15 minutes, preferably within 10 minutes.

2. Method according to claim 1 , wherein at least one susceptibility characteristic relates to the amount of antimicrobial responsive biomolecules extracellularly secreted by a fraction of the captured pathogenic microorganisms.

3. Method according to claim 1 or claim 2, wherein at least one susceptibility characteristic relates to the type of antimicrobial responsive biomolecules extracellularly secreted by a fraction of the captured pathogenic microorganisms.

4. Method according to any of the claims 2-3, wherein at least one susceptibility characteristic relates to a ratio of the amount and / or the type antimicrobial responsive biomolecules extracellularly secreted by a fraction of thecaptured pathogenic microorganisms relative to non-antimicrobial responsive biomolecules secreted by a fraction of the captured pathogenic microorganisms.

5. Method according to any of the preceding claims, wherein at least one susceptibility characteristic relates to the composition of antimicrobial responsive biomolecules extracellularly secreted by a fraction of the captured pathogenic microorganisms.

6. Method according to any of the preceding claims, wherein in step D) at least one susceptibility profile is determined which is formed by a combination of a plurality of susceptibility characteristics, and wherein in step E) at least one susceptibility profile is compared with at least one reference profile which is formed by a combination of reference characteristics.

7. Method according to any of the preceding claims, comprising a step F) of identifying at least a fraction of the extracellularly secreted antimicrobial responsive biomolecules and determining the type of antimicrobial responsive biomolecules extracellularly secreted by at least a fraction of the captured pathogenic microorganisms and / or determining the composition of antimicrobial responsive biomolecules extracellularly secreted by at least a fraction of the captured pathogenic microorganisms, wherein step F) is performed after step C).

8. Method according to any of the preceding claims, comprising a step G) of analysing at least one fluid comprising at least one antimicrobial compound to be applied to and / or applied to at least part of the at least one catch filter and determining at least one reference characteristic of said analysed fluid.

9. Method according to any of the preceding claims, comprising a step H) of providing at least one reference fluid which corresponds to the fluid to be applied or applied in step C), wherein the reference fluid is free from antimicrobial compound.

10. Method according to claim 9, comprising a step of analysing said reference fluid and determining at least one reference characteristic corresponding to the reference fluid.11 . Method according to any of the preceding claims, comprising a step I) of analysing the at least one catch filter and determining at least one reference characteristic of said at least one catch filter, wherein step I) is performed prior to step C).

12. Method according to any of the preceding claims, wherein step D) is repeated at least at two different time points.

13. Method according to any of the preceding claims, comprising a step J) of dividing at least one body fluid sample in at least two separate sample parts, and wherein at least steps B) and C) are performed separately for at least two separate sample parts.

14. Method according to claim 13, wherein a concentration of at least one antimicrobial compound in the fluid applied in step C) is different for the separately performed steps C) for at least two separate sample parts.

15. Method according to claim 13 or claim 14, wherein the type of antimicrobial compound in the fluid applied in step C) is different for the separately performed steps C) for at least two separate sample parts.

16. Method according to any of the claims 9-10 and any of the claims 13-15, wherein during at least one separately performed step C) at least one reference fluid is applied instead of at least one fluid comprising at least one antimicrobial compound, thereby forming a reference sample part.

17. Method according to claim 16, comprising a step of analysing the reference sample part and determining at least one reference characteristic of the analysed reference sample part.

18. Method according to any of the preceding claims, wherein step D) is performed by means of Raman Spectroscopy, in particular Surface-Enhanced Raman Spectroscopy (SERS), and / or biochemical analysis and / or electrical analysis.

19. Method according to any of the preceding claims, comprising step K) of concentrating at least part of at least one fluid in which the captured pathogenic microorganisms and / or the extracellularly secreted antimicrobial responsive biomolecules are suspended, such that the concentration of captured pathogenic microorganisms and / or the concentration of extracellularly secreted antimicrobial responsive biomolecules is increased.

20. Method according to claim 19, wherein step K) is performed by heating.21 . Method according to any of the preceding claims, comprising a step L) of filtering at least one body fluid sample through at least one coarse filter which is configured for removing at least a fraction of particles from the body fluid sample, in particular particles which are larger than pathogenic microorganisms.

22. Method according to any of the preceding claims, wherein at least a part of the catch filter is coated with nanoparticles, in particular SERS-active nanoparticles to form a SERS substrate.

23. Method according to any of the preceding claims, comprising a step M) of filtering at least one solution comprising nanoparticles, in particular SERS-active nanoparticles through the catch filter such that at least part of the catch filter will be coated with said nanoparticles.

24. Device for processing at least one body fluid sample for analysing antimicrobial compound susceptibility of pathogenic microorganisms in at least one body fluid sample, comprising:- at least one housing, comprising: o at least one retaining structure for separately and / or independently retaining a plurality of analysis catch filters and at least one reference catch filter, o a plurality of analysis reservoirs each configured for receiving at least one fluid comprising at least one antimicrobial compound, and o at least one reference reservoir configured for receiving at least one reference fluid, wherein the analysis reservoir and the reference reservoir are located at a distance from each other,- optionally, a plurality of analysis catch filters and at least one reference catch filter configured to capture at least a fraction of pathogenic microorganisms from a body fluid sample, wherein at least one housing is a modular housing which is adjustable between:- a filtering configuration, wherein at least one body fluid sample can be filtered through at least one analysis catch filter retained in at least one retaining structure and wherein at least one body fluid sample can be filtered through at least one reference catch filter retained in at least one retaining structure; and- a processing configuration, wherein at least one retaining structure is positioned adjacent to at least part of at least one analysis reservoir such that fluid comprising at least one antimicrobial compound received in at least one analysis reservoir can get into contact with at least part of at least one analysis catch filter retained in the at least one retaining structure, and wherein at least one retaining structure is positioned adjacent to at least part of at least one reference reservoir such that at least one reference fluid received in at least one retaining reservoir can get into contact with at least part of at least one reference catch filter retained in the at least one retaining structure.

25. Device according to claim 24, wherein at least one retaining structure is displaceable at least between the filtering configuration and the processing configuration.

26. Device according to any of the claims 24 to 25, wherein in the processing configuration at least one analysis catch filter retained in the retaining structure at least partially covers the at least one analysis reservoir and / or wherein at least one reference catch filter retained in the retaining structure at least partially covers the at least one reference reservoir.

27. Device according to any of the claims 24 to 26, comprising at least one sealing member configured to couple at least one analysis reservoir and at least one retaining structure in a liquid-proof or liquid-tight manner, preferably at least in the processing configuration and / or wherein at least one sealing member is configured to couple the at least one reference reservoir and the retaining structurein a liquid-proof or liquid-tight manner, preferably at least in the processing configuration.

28. Device according to any of the claims 24 to 27, wherein at least one reference reservoir and / or at least one analysis reservoir and / or at least one retaining structure are detachably connected to the housing.

29. Device according to any of the claims 24 to 28, wherein at least part of at least one reference reservoir and / or at least part of at least one analysis reservoir comprises a translucent or transparent portion.

30. Device according to any of the claims 24 to 29, wherein the housing comprises at least one application opening for passaging at least one body fluid sample, wherein in the filtering configuration at least one application opening is aligned with at least one analysis catch filter for passaging at least one body fluid sample through the at least one analysis catch filter and / or wherein at least one application opening is aligned with at least one reference catch filter for passaging at least one body fluid sample through the at least one reference catch filter.31 . Device according to any of the claims 24 to 30, comprising at least one sample applicator for applying at least one body fluid sample to at least one reference catch filter and / or to at least one analysis catch filter at least in the filtering configuration.

32. Device according to claim 30 and claim 31 , wherein the sample applicator is connected or connectable to at least one application opening.

33. Device according to any of the claims 24 to 32, wherein the housing defines at least one accommodation space configured to at least partially accommodate at least one coarse filter which is configured for removing at least a fraction of particles from at least one body fluid sample, in particular particles which are larger than pathogenic microorganisms, and preferably wherein the at least one accommodation space is at least partially aligned with at least one analysis catch filter and / or at least one reference catch filter retained by the retaining structure, at least in the filtering configuration.

34. Device according to any of the claims 24 to 33, wherein the housing comprises at least one processing opening for passaging fluid to at least one analysis reservoir and / or to at least one reference reservoir, wherein at least one processing opening is at least partially aligned with at least one analysis reservoir in the processing configuration for passaging fluid comprising at least one antimicrobial compound to the at least one analysis reservoir and / or wherein at least one processing opening is at least partially aligned with at least one reference fluid reservoir in the processing configuration for passaging reference fluid to the at least one reference reservoir.

35. Device according to any of the claims 24 to 34, comprising at least one fluid applicator for applying at least one fluid to at least one analysis reservoir or to at least one reference reservoir in the processing configuration.

36. Device according to claim 35, wherein at least one fluid applicator comprises a solution comprising SERS-active nanoparticles to be filtered through at least one analysis catch filter and / or at least one reference catch filter retained in the retaining structure such that at least part of the at least one analysis catch filter and / or the at least one reference catch filter, respectively, will be coated with SERS-active nanoparticles thereby forming a SERS substrate.

37. Device according to claim 34 and any of the claims 35-36, wherein at least one fluid applicator is connectable to at least one processing opening for passaging fluid from the fluid applicator to at least one analysis reservoir and / or at least one reference reservoir in the processing configuration.

38. Device according to any of the claims 24 to 37, wherein the retaining structure comprises at least two inlets, wherein a first inlet is at least partially aligned with at least one reference reservoir in the processing configuration for passaging reference fluid to at least one reference reservoir and wherein a second inlet is at least partially aligned with at least one analysis reservoir in the processing configuration for passaging fluid comprising at least one antimicrobial compound to at least one analysis reservoir.

39. Device according to claim 34 and claim 38, wherein at least one processing opening and the first inlet together form a fluid conduct in the processing configuration for guiding reference fluid to the reference reservoir and / or wherein at least one processing opening and the second inlet together form a fluid conduct in the processing configuration for guiding fluid comprising at least one antimicrobial compound to the analysis reservoir.

40. Device according to any of the claims 24 to 39, comprising at least one absorbing body for absorbing a fraction of fluid comprising at least one antimicrobial compound and / or for absorbing a fraction of reference fluid.41 . Device according to claim 40, wherein at least absorbing body is provided adjacent to the analysis reservoir and / or to the reference reservoir.

42. Use of the device according to any of the claims 24-41 in a RamanSpectrometer for analysing antimicrobial compound susceptibility of pathogenic microorganisms in body fluid samples.

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