Device and method for measuring the erythrocyte sedimentation rate and corresponding kit

Abstract

Manual device (10) for measuring the erythrocyte sedimentation rate comprising a reading chamber (20) containing a radiation emitter (22) and a corresponding radiation receiver (23), facing each other, and a fluidic channel (21) configured to receive a blood sample and made through between the emitter (22) and the receiver (23).

Description

[0001] “DEVICE AND METHOD FOR MEASURING THE ERYTHROCYTE SEDIMENTATION RATE AND CORRESPONDING KIT”

[0002]

[0003] FIELD OF THE INVENTION

[0004] The present invention concerns a device for measuring the erythrocyte sedimentation rate, in particular starting from a single drop of blood, as well as a corresponding measuring method and a corresponding kit.

[0005] BACKGROUND OF THE INVENTION

[0006] The erythrocyte sedimentation rate (hereafter ESR) is a well-established and known test for the detection of a general inflammatory state. The reference method, known as the Westergreen method, is performed by sedimentation of a blood sample and the result is obtained after about one hour from when a tube is filled. The method was implemented over time by the Applicant and was speeded up in order to obtain the result in 20 seconds, thereby allowing to integrate the ESR into blood cell counter type systems so as to optimize a workflow obtainable from a blood collection tube with EDTA.

[0007] Around 400 million tests are performed worldwide every year using the Westergreen method and partly with automated systems.

[0008] One problem is that to date ESR measurement devices are generally stand-alone and require blood sample treatment times that prolong the time required to obtain the measurement result. For example, after collecting a blood sample, it is necessary to introduce it into a laboratory device to perform the measurement; once the measurement is complete, it is necessary to empty the blood introduced into the tubes that are inside the devices, which means that the time between two successive measurements on different samples is prolonged.

[0009] Another disadvantage of known devices for measuring the ESR is the need to collect volumes of blood that could still be decreased, albeit by a few milliliters. US-A 1-2024 / 192126 discloses a manual device and method for analyzing a blood sample, equipped with a capillary tube that can be inserted into a spectrometer to be analyzed. This device does not comprise a radiation emitter and receiver, these elements being described as being external to this device.

[0010] WO-A 1-2011 / 101815 discloses a fixed type device, that is, installed on a support and included in a temperature-controlled box. This device is therefore not manual or portable. A solenoid is also provided to move the blood sample forward and backward by making the tube in which the sample is inserted vibrate.

[0011] US-A1-2015 / 300937 concerns an ESR reading device of a known type, to be installed in a fixed machine structured to receive tubes through which blood samples are made to flow by means of displacement means, in particular pumps. US-A 1-2001 / 266778 discloses a cartridge in which a capillary tube is inserted, for collecting and analyzing a blood sample taken directly from a drop of blood. This cartridge is provided for sample collection only, and requires an external analysis device. Therefore, the cartridge is not equipped with a radiation emitter and receiver.

[0012] US-A 1-2020 / 340888 concerns a portable device with disposable samplecarrying tubes, for measuring the level of glucose in the blood, but not for measuring the ESR. The sample-carrying tube contains, in an internal channel thereof, a reading zone in which a reagent that changes color after reacting with the blood is immobilized. Measurements are performed when the sample is stationary.

[0013] There is therefore the need to perfect a device for detecting and measuring the ESR, as well as a measuring method that uses the device, which can overcome at least one of the disadvantages of the state of the art.

[0014] To do this, it is necessary to solve the technical problem of reducing blood sample processing times as much as possible.

[0015] One purpose of the present invention is to provide a device and perfect a method for measuring the ESR from a blood sample with the fewest possible steps.

[0016] Another purpose of the present invention is to provide a device and perfect a method for measuring the ESR which allow to collect smaller volumes of blood compared to known devices and methods, and which can be used substantially in any circumstance and by any person whatsoever, even unqualified persons.

[0017] The Applicant has devised, tested and embodied the present invention to overcome the shortcomings of the state of the art and to obtain these and other purposes and advantages.

[0018] SUMMARY OF THE INVENTION

[0019] The present invention is set forth and characterized in the independent claims. The dependent claims describe other characteristics of the present invention or variants to the main inventive idea.

[0020] The present invention allows to measure the ESR from a single drop of blood by pricking a finger with a specific, commercially available lancet. The new invention allows to carry out the ESR test even at the patient’s bedside, it can be used in a doctor’s office, in pharmacies, or directly by the patient as a self-test.

[0021] In accordance with the above purposes, a manual device according to the present invention for measuring the erythrocyte sedimentation rate comprises a body that also serves as a handgrip, a reading chamber containing a radiation emitter and a corresponding radiation receiver, the emitters facing each other, and a fluidic channel, developing from an inlet aperture, made through between the radiation emitter and the radiation receiver and configured to receive a capillary tube suitable to contain a blood sample. For this purpose, the fluidic channel is tubular or substantially tubular shaped.

[0022] The body can be tubular or have a different shape, as long as it can serve as a handgrip.

[0023] By ‘manual device’ it is understood that the device is portable, usable with one hand and without any particular effort, which functions autonomously, without being physically connected to another device or apparatus. The sizes of such a device can even be such as to make it pocket-sized.

[0024] The manual device according to the invention is simple to use and has very small sizes, in particular it can have the shape and size of a pen.

[0025] Advantageously, the aforementioned inlet aperture is made exactly on an external surface of the device itself. This means that the inlet aperture of the fluidic channel is not inside the device. This allows to simplify the device’s structure and to simplify the insertion of a capillary tube into the fluidic channel. The capillary tube is, in fact, insertable and extractable into / from the fluidic channel without the aid of any tool whatsoever, and does not require any other operation whatsoever, such as the removal of a block or plug for example. The sizes of the fluidic channel and of the capillary tube can be such that the insertion of the capillary tube into the fluidic channel is stable by interference. Optionally, an element for retaining the capillary tube, or for holding it in position, can be provided at the bottom of the fluidic channel.

[0026] The device according to the invention allows for a sample collection procedure and use by any type of operator whatsoever, or for self-testing. After pricking the selected finger or toe with the lancet, the punctured area is pressed to obtain a drop of blood. The device according to the invention is equipped with a single use, that is, disposable, capillary, preferably made of plastic or glass material, which when brought into contact with the drop of blood, draws the blood by capillary suction. When the blood sample is collected, the capillary is inserted into a reading channel, or fluidic channel, inside which there is a photodiode that detects the presence of blood and its flow.

[0027] According to some embodiments, the reading chamber is placed in an end portion advantageously removably connected to a first end of the body. The end portion can be pointed. The fluidic channel is included in the end portion.

[0028] The device can comprise an activation button configured to activate the ESR measurement function.

[0029] Thanks to the use of a capillary tube, the sample is moved through capillary action, without any pump of any kind, particularly peristaltic, suitable to move the sample inside the reading chamber. The device according to the invention does not, in fact, have a pump or any other type of mean for moving the blood sample in the capillary tube, or even the capillary tube itself.

[0030] In this sample collection step, the sampling system is in the Flow step. Once the capillary is filled, the ESR detection system is in the Stop step. These two steps are advantageously determined by the suction of the blood through capillary action, and by its stop when the suction through capillary action ends, for example, if the blood reaches the other end of the capillary tube or if it is somehow blocked by a member for blocking or closing the channel through which it flows.

[0031] A photodiode inside the channel in which the capillary tube that collected the venous blood is located detects, in the Flow step, the presence of the sample and, in the Stop step, the formation of the roleaux that characterize ESR measurement. To optimize the collection of a blood sample from a finger, the device can be positioned on a horizontal support surface, and the patient brings the pricked finger and the drop of blood close to the capillary which will cause the collected blood to flow through the capillary through suction. The device can also be inclined with respect to the horizontal, without however being oriented vertically. For example, the device can be inclined by an angle comprised between 10° and 80° with respect to the horizontal, preferably between 20° and 70°, more preferably between 30° and 60°, even more preferably between 40° and 50°. Generally, an angle less than 50° with respect to the horizontal favors the outflow of the sample through capillary action.

[0032] The capillary was previously inserted in the device and housed in a channel inside which there is a photodiode for detecting the flow and stop steps.

[0033] The ESR measurement is based on the detection of the formation of corpuscular aggregates, or roleaux, which, depending on their concentration, will make the transmission of light detected by the photodiode vary. In the absence of roleaux, light transmission will be maximum, thus resulting in a zero ESR response; if aggregates or roleaux are present, the light transmission will be reduced and therefore the light correlation, through a calculation algorithm, will define an ESR value corresponding to the ESR equivalence using the Westergreen model, which provides for measurement within 1 hour of sedimentation.

[0034] The device according to the invention allows to detect the presence of aggregates determined by roleaux in just 10 seconds from the moment the blood sample of a few milliliters (from 10 to 50) is collected for the ESR measurement. After the test has been performed, the capillary used is removed from its channel for insertion in the device and the system is ready for further testing. The device according to the invention is therefore always ready to be used for clinical use at the patient’s bedside, or by pharmacy staff, or by doctor’s office staff, or by the patient themselves for self-testing.

[0035] The device according to the invention is configured to perform the ESR measurement within a few seconds of collecting the blood sample, for example, in about 8-10 seconds.

[0036] The device and method according to the invention allow to measure the ESR using a single drop of venous blood, without the addition of any anticoagulant. With the device and method according to the invention, a single drop of blood can be used without the need to mix the sample, since the roleaux components, if present, are not affected by any delay in performing the test.

[0037] The present invention favors the use of plastic capillaries in order to obtain a correct reading of the sample through the aggregate or roleaux detection photodiode. The plastic capillary has a peculiar opalescence suitable to not generate any interference with the photodiode during sample reading.

[0038] Advantageously, the method provides a calculation algorithm based on the temporal reading of the sample placed inside the plastic capillary. The calculation algorithm provides a reading at time zero, that is, detection of the blood sample that has entered the plastic capillary, and a final reading, for example, at the 10thsecond of its residence in the capillary.

[0039] The calculation algorithm improves the execution times of the stop and flow process, and provides a response in terms of ESR values that are correlated with the classic Westergreen sedimentation into classes of belonging of the sample itself. The ESR classes report low or normal values, average values considered at risk of inflammation, and high values for which the patient should verify their general inflammatory state with other tests. The values for the three classes are indicatively: normal state from 2 to 30 mm / h, average values from 30 to 45 mm / h, high values from 45 to 120 mm / h.

[0040] The device according to the invention is the first instrument usable as a self-test or at the patient’s bedside to monitor the inflammatory state in a clinical setting. The invention allows to carry out rapid ESR measurement starting from just a few microliters of venous blood; for example, 10 microliters are sufficient to fill the reading capillary tube for a length of approximately 5 centimeters.

[0041] According to some embodiments, the device comprises a remote communication module for communicating the ESR measurement results with a remote processing unit. The communication module can be of the 4G / 5G, Wi-Fi, Bluetooth type, or suchlike, configured to communicate with a processing unit, for example of a computer, tablet, smartphone, or suchlike.

[0042] In accordance with some embodiments, the detector element is a photosensor, for example a photodiode. This allows to perform capillary photometry. It also allows for a quantitative ESR measurement from 2 to 120 mm / h, with standard values correlated with the Westergreen reference method, or allows for a quantitative ESR measurement at three different levels: low (2-30 mm / h), medium (30-45 mm / h), and high (45-120 mm / h).

[0043] As an alternative to the aforementioned electromagnetic wave emitter / detector system, a system for emitting / receiving acoustic waves at various frequencies can be provided. In accordance with some embodiments, the emitter and / or the receiver are integrated into the internal surface of the fluidic channel. That is, the emitter and / or the receiver have at least one portion of their surface that coincides with the internal surface of the fluidic channel. In this way, when a capillary tube is inserted therein, the emitter and / or the receiver are in direct proximity to the tube, if not in contact therewith. This also allows to reduce the distance between the emitter and receiver, as well as reduce the external sizes of the device.

[0044] According to some embodiments, the device comprises an integrated screen to display the ESR measurement result. The display screen supplies end-of-test data in the standard reading range with value labels for level classes, specifically low, medium, or high.

[0045] In accordance with another aspect of the present invention, a method for measuring the erythrocyte sedimentation rate provides a step of collecting a blood sample by means of a capillary tube, and a step of analyzing the blood sample by means of a device for measuring the erythrocyte sedimentation rate as indicated above.

[0046] Advantageously, the analysis step provides a stop and flow type analysis of the blood sample, performed however within a microfluidic channel (or channels) placed in contact with a drop of blood. More advantageously, the microfluidic channel is constituted by the capillary tube, in particular by its internal channel. For example, the analysis step provides a sub-step of outflow of the blood sample into the capillary tube located inside the device, in order to measure the erythrocyte sedimentation rate, followed by a sub-step of stopping the blood sample so that a part of the blood sample remains stationary in the reading chamber, a step of emitting and detecting a radiation beam, by means of the emitter and detector, in order to measure the erythrocyte sedimentation rate in the blood sample.

[0047] In particular, the sub-step of outflow of the sample occurs exclusively through capillary action, or capillary suction of the sample into the internal channel of the capillary tube. The sub-step of stopping the sample occurs through interruption of the capillary suction, for example, because the sample reaches the other end of the capillary tube, or because of an obstacle suitable to stop the outflow.

[0048] In accordance with some embodiments, the method provides, during the step of emitting and detecting the electromagnetic or acoustic radiation beam, a step of measuring the erythrocyte sedimentation rate (ESR), which advantageously provides to detect the presence of (macro)aggregates or roleaux in the blood sample. The presence of aggregates or roleaux allows to determine the erythrocyte sedimentation rate.

[0049] Favorably, the blood sample collection step is performed with a simple drop of blood.

[0050] According to some embodiments, the blood sample collection step provides to put the free end of a capillary tube in contact with a drop of blood. Preferably, the drop of blood is obtained by pricking the skin, for example, in correspondence with the tip of a finger. Advantageously, the skin is pricked with the aid of a finger prick lancet.

[0051] In accordance with some embodiments, the method provides that the capillary tube is already inserted in the device for measuring the erythrocyte sedimentation rate when the blood sample is collected.

[0052] In accordance with some embodiments, the method provides to communicate the measurement results to a processing unit, via the communication module. In particular, the results are communicated wirelessly, for example via Wi-Fi, 4G / 5G data, Bluetooth, or suchlike. The processing unit is a smartphone, a computer, or suchlike.

[0053] The ESR measurement can be performed using three-level capillary photometry, specifically low level (2-30 mm / h), medium level (30-45 mm / h), and high level (45-120 mm / h). Alternatively, the ESR measurement can be performed using capillary photometry from 2 to 120 mm / h, according to standard values correlated with the Westergreen reference method.

[0054] According to some embodiments, the blood sample can be collected from a pediatric test tube.

[0055] According to some embodiments, the blood sample can be collected from blood bags from transfusion-prepared donors.

[0056] In accordance with another aspect, a kit for measuring the ESR comprises a device for measuring the ESR as indicated above and one or more capillary tubes for collecting a blood sample.

[0057] According to some embodiments, the one or more capillary tubes each comprise, at one end thereof, a respective filter configured to block the outflow of the blood sample, thus guaranteeing the sample flow stop function. That is, each capillary tube is closed, in correspondence with one end thereof, by a filter, preferably inserted in the internal channel of the capillary tube. The filter preferably allows air to pass through.

[0058] Advantageously, the capillary tube is of a plastic or glass nature.

[0059] Advantageously, the capillary tube is disposable.

[0060] Advantageously, the capillary tube has a round, square, or rectangular crosssection.

[0061] According to some embodiments, the kit also comprises a finger prick lancet. The ESR test directly from a blood drop is innovative in the method and in its application for POC or DO and Self-Test by any person or patient whatsoever. The test also finds application in a pediatric context, thanks to its simplicity of execution and the minimal amount of blood collected by means of the device. The present patent application concerns both the technical structure as well as the type of native blood sample collected from a finger prick using a lancet.

[0062] DESCRIPTION OF THE DRAWINGS

[0063] These and other aspects, characteristics and advantages of the present invention will become apparent from the following description of an embodiment, given as a non-restrictive example with reference to the attached drawings wherein:

[0064] - fig. 1A is a perspective view of a device for measuring the erythrocyte sedimentation rate according to the present invention;

[0065] - fig. IB is a section view of a reading chamber of the device shown in fig. 1; - figs. 2 and 3 A are lateral views of the device of fig. 1, in a step of insertion of a capillary tube and when it is ready for use, respectively;

[0066] - fig. 3B is a section view of the reading chamber of the device of fig. 3 A;

[0067] - figs. 4 and 5A are lateral views of the device of figs. 2 and 3A in two successive steps of placement in contact with a drop of blood and collection of a blood sample, respectively;

[0068] - fig. 5B is a section view of the reading chamber of the device shown in fig. 5A; and

[0069] - figs. 6 and 7 are lateral views of the device for measuring the ESR of figs. 4 and 5A during a step of reading the ESR value and a subsequent step of removing the capillary tube, respectively.

[0070] We must clarify that the phraseology and terminology used in the present description, as well as the figures in the attached drawings also in relation as to how described, have the sole function of better illustrating and explaining the present invention, their purpose being to provide a non-limiting example of the invention itself, since the scope of protection is defined by the claims.

[0071] To facilitate comprehension, the same reference numbers have been used, where possible, to identify identical common elements in the drawings. It is understood that elements and characteristics of one embodiment can be conveniently combined or incorporated into other embodiments without further clarifications. DESCRIPTION OF AN EMBODIMENT OF THE PRESENT INVENTION

[0072] The attached drawings show the distinctive feature of the device according to the invention that allows to perform an ESR test in less than 10 seconds from the collection of a drop of blood after finger pricking with a specific lancet, or from a pediatric test tube.

[0073] With reference to fig. 1, a manual device 10 for measuring the ESR is of the type with external sizes similar to those of a pen, which performs the ESR test from capillary blood collected from a drop of blood.

[0074] The device 10 thus comprises a tubular body 11 and a pointed end portion 12 (hereafter tip, for simplicity), advantageously removably connected to a first end 11 A of the body 11.

[0075] At the second end 1 IB of the body 11 there is provided a first button 13 located coaxially with the body 11 and configured to be pressed. The button 13 commands the activation of the erythrocyte sedimentation rate measurement of a sample S of blood collected through the terminal capillary. The outflow of the sample S along the capillary occurs exclusively through capillary action. For this purpose, an internal channel 14 is provided that runs through the body 11, advantageously coaxial therewith.

[0076] The tip 12 encloses a reading chamber 20 in which a fluidic channel 21 is provided for housing a capillary tube 30, as well as an LED emitter 22 and an LED receiver 23, corresponding to the LED emitter 22, which are located facing each other in axially symmetrical positions in the internal wall of the channel 21. We must clarify that the LEDs 22 and 23 have a surface thereof facing directly inside the channel 21 that is at least partly coincident with the internal surface of the channel 21, or at least partly flush therewith. In this way, when a capillary tube 30 is inserted inside the channel 21, the surfaces of the LEDs 22 and 23 are in immediate proximity to, or even in contact with, the capillary tube 30, in particular its external surface (fig. 3B).

[0077] The channel 21 is configured to house a capillary tube 30 and develops from an inlet aperture 24 located at the external end 12A of the tip 12, to a bottom 25 located in correspondence with a second end 12B of the tip 12. This second end 12B of the tip 12 is connected to the first end 11 A of the body 11.

[0078] The bottom 25 has a section of a smaller lateral size than the lateral size of the fluidic channel 21, to allow to block the travel of the capillary tube 30, leaving the fluidic channel 21 in fluidic communication with the internal channel 14 of the body 11. For this purpose, the fluidic channel 21 and the internal channel 14 of the body 11 are aligned.

[0079] The device 10 also comprises, on the lateral wall of the body 11 , a second button 15 for expelling a blood collection capillary tube 30 from the channel 21, in order to avoid any contact of an operator with potentially infected material.

[0080] The device 10 also comprises an integrated screen 16, or display, for displaying an ESR measurement result. The display is positioned on the external wall of the body 11. In particular, at the end of the test, the display 16 presents the ESR value obtained from a drop of blood or from a pediatric test tube.

[0081] The ESR test is therefore carried out on a sample S of native blood collected by means of a capillary tube 30 that is of the disposable type useful for each sequential execution of the ESR test. The tube 30 can have a round (as shown in the drawings), square or rectangular section.

[0082] The capillary tube 30 is advantageously equipped with a closing filter 31 in a terminal part thereof. The filter 31 is made of porous material such as to block the blood but to allow air to pass, so as to maintain the fluidic communication between the internal channel 14 of the body and the capillary tube 30.

[0083] The tube 30 can be of plastic or glass material.

[0084] The tube 30 can comprise, in its terminal part, an RFID transmitter so as to couple a signal from the same tube 30 and acceptance by the device 10. We must however clarify that the internal channel of the tube 30 is without any element or agent immobilized on its internal surface, so as not to alter or prevent the normal outflow of the blood through capillary action. This normal outflow is important for the proper measurement of the ESR.

[0085] The volume of blood drawn from the capillary tube 30 necessary to perform the ESR test ranges from 30 to 150 microliters of drawn blood.

[0086] The manual device 10 is the only instrument capable of performing an ESR test by means of collection from drop of blood executable for Doctor Office or Self¬ Test use, or as a pharmacy test.

[0087] The operation of the device 10 for measuring the ESR described heretofore is as follows.

[0088] The device 10 performs the test using a disposable capillary tube 30 for the collection of a blood sample S. The capillary tube 30 is first inserted into the fluidic channel 21 through the inlet aperture 24 (fig. 2). The capillary tube 30 is oriented so that the filter 31 is positioned at the bottom 25 of the fluidic channel 21, while the opposite end of the capillary tube 30 protrudes from the tip 12 (figs. 3A-3B).

[0089] The skin of a patient is pricked, for example on a finger 40, to let out a simple drop G of blood, in a known manner by means of a finger prick lancet, and the free end of the capillary tube 30 is placed in contact with the drop G (fig. 4). The blood begins to flow into the capillary tube 30 through capillary action.

[0090] During this sample collection step, the device 10, in particular the capillary tube 30 inserted therein, is positioned horizontally, or inclined with respect to the horizontal by an angle not greater than 80°, preferably not greater than 50°, more preferably not greater than 45°. The blood, due to the capillary action created by the capillary tube 30, flows inside the reading chamber 20 and automatically stops between the two emitter 22 and receiver 23 LEDs positioned in opposite directions to each other (fig. 5B). The first button 13 is then pressed in order to activate the operation of the device 10 and to command the execution of the ESR measurement. From the moment the first button 13 is pressed, the LEDs 22 and 23 measure the ESR in a time of about 10 seconds.

[0091] The blood sample S reading function and the calculation algorithm record the blood flow during suction into the capillary tube 30, until the blood sample S stop determined by the filter 31 (fig. 5B).

[0092] The classic flow and stop function to measure the ESR is generated automatically by the capillary action within the capillary tube 30 (flow) and stopped in the flow by the filter 31, if present in the capillary tube 30 (stop) at its end in the bottom 25 of the channel 21. Alternatively, the outflow of the sample S into the capillary tube 30 can stop on its own, for example when the sample S reaches the opposite end of the capillary tube 30.

[0093] The ESR calculation is then performed using a dedicated algorithm. At the end of the calculation, the result is shown on the display 16 (fig. 6), for example in the form of a numerical value possibly accompanied by a wording of the type “High ESR”, “Medium ESR” or “Low ESR”, for an immediate visual result of the patient’s inflammatory state.

[0094] The second button 15 is then pressed to eject the used capillary tube 30 (fig. 7), preferably so that it falls directly into a receptacle for its disposal, for example a basket.

[0095] The mathematical algorithm of the device 10 for measuring the ESR is comparable in its results to a classic Westergreen sedimentation system according to NCLS standards.

[0096] The measured and calculated data can be stored on a phone with a dedicated app, in order to monitor the various tests and self-tests performed over time, for the attending physician to check.

[0097] The device 10 can also be used upon admission by an accident and emergency doctor, at a patient’s bedside or for blood donors who have to be in good health without having inflammatory states for which the ESR is a test recognized as a marker of generic inflammation.

[0098] Among other advantages of the device 10, the use of blood drop sample collection improves the operating standards of the critical issues described by NCLS in various technical and operational aspects indicated below.

[0099] The blood drop test is not subject to laboratory room temperature control, since the test is performed at the time of the finger prick using a lancet and of the sample S collection.

[0100] The blood drop test is also not subject to the use of any anticoagulant, since the test is immediate from the time mentioned above.

[0101] The blood drop G test is not subject to any need to mix the blood sample S, and thus detect the formation of roleaux characteristic for ESR measurement. The roleaux are detected during blood flow in the stop timing.

[0102] The device 10 also performs the ESR value reading function at 3 levels: low, border line, high, to simplify the identification of the patient’s status. Specifically, after the ESR test, in addition to the numerical value readable on the display, the words “low”, “border line” or “medium”, or “high”, or similar equivalent captions will also appear.

[0103] The operational functions of the device 10 can be verified by using lactics to monitor the correct technical operation. Control lactics are validated on other instrumentation, in a known manner.

[0104] The device 10 is a portable instrument and therefore usable in all self-testing control contexts to monitor one’s self, or migrant flows, or refugee camps or airport checks points.

[0105] The device 10 is practical, simple to use and the cost of the test is attributable to the value of the disposable capillary.

[0106] The device 10 has a production cost compatible with a use by organizations such as the WHO, for poor countries and therefore also has a social economic function of great advantage compared to any existing instrument on the market.

[0107] EXPERIMENTAL PART

[0108] It has been verified that the inclination of the manual device 10, in particular at the moment when the free end of the capillary tube 30 comes into contact with the drop G of blood, has an impact on the blood’s outflow rate into the capillary tube 30, as well as on the distance travelled by the blood sample. In a test performed by the Applicant, capillary tubes were used to collect a blood sample through contact with a drop of blood. The capillary tubes were positioned horizontally, inclined by 45° with respect to the horizontal and vertically.

[0109] In each position, it was observed that a plateau was reached, corresponding to the maximum distance traveled by the blood sample in the capillary tube. In essence, it was observed that the maximum distance (about 75 mm) traveled by the sample, as well as the maximum average speed (about 10.5 mm / s), is achieved in the horizontal position. In the vertical position, on the other hand, the minimum distance (17 mm) and the minimum average speed (4.30 mm / s) between the three tested angles were achieved, the results achieved with the 45° angle being intermediate (approximately 30 mm and 7.5 mm / s, respectively). The tests were carried out with capillary tubes with an internal diameter of 0.8 mm and a length of 100 mm. The samples were collected from drops of blood with a volume of 250 pL.

[0110] No bubbles were observed during the capillary travel in each sample tested. It was also observed that after about 7 seconds the sample stops autonomously, whatever the angle of the capillary tube.

[0111] It can be seen from the foregoing description that the present invention, in addition to speeding up the analysis times to obtain an ESR value, allows to miniaturize a device 10 for measuring the ESR and to simplify its use to the extreme, even with regard to obtaining the blood sample S. This makes the ESR measurement device 10 usable even in the absence of medical personnel, for example in the home. The device 10 can also be used, as well as for humans, also on animals.

[0112] For this reason, a kit is provided containing a device 10 for measuring the ESR as described above and at least one capillary tube 30, preferably packaged in a protective packaging. It can be provided that the kit contains a finger prick lancet. The capillary tube 30 contains an optional filter 31 that closes one end thereof, so as to block the blood flow, but which allows air to pass in order to maintain air communication between the internal channel 14 of the body and the channel 21 for housing the capillary tube 30, positioned in the tip 12. As shown in the drawings, the filter 31 is advantageously inserted inside the internal channel of the capillary tube 30 in correspondence with one end thereof, so as to close it. As mentioned above, the internal channel of the tube 30 is without any element or agent immobilized on its internal surface, so as not to alter or prevent the normal outflow of the blood through capillary action.

[0113] It is clear that modifications and / or additions of parts may be made to the device 10 and to the method as described heretofore, without thereby departing from the field and scope of the present invention, as defined by the claims.

[0114] It is also clear that, although the present invention has been described with reference to some specific examples, a person of skill in the art will be able to achieve other equivalent forms of device and method for measuring the erythrocyte sedimentation rate and corresponding kit, having the characteristics as set forth in the claims and hence all coming within the field of protection defined thereby. In the following claims, the sole purpose of the references in brackets is to facilitate their reading and they must not be considered as restrictive factors with regard to the field of protection defined by the claims.

Claims

CLAIMS1. Manual device (10) for measuring the erythrocyte sedimentation rate comprising a body (11), a reading chamber (20) with an inlet aperture (24) for a fluidic channel (21) made through between a radiation emitter (22) and receiver (23), substantially tubular in shape, configured to stably receive a disposable capillary tube (30) suitable to contain a blood sample (S) consisting of a drop of a few microliters.

2. Device (10) as in claim 1, characterized in that it comprises a pointed end portion (12) connected to an end (HA) of said tubular body (11) so as to form a lancet, said reading chamber (20) being contained in said end portion (12).

3. Device (10) as in claim 2, characterized in that said end portion (12) is removably connected to said end (11 A) of said body (11).

4. Device (10) as in any claim hereinbefore, characterized in that said radiation emitter (22) and / or said radiation receiver (23) are integrated in the internal surface of said fluidic channel (21).

5. Method for measuring the erythrocyte sedimentation rate, comprising a step of collecting a blood sample (S) consisting of one drop and a step of analyzing said blood sample (S) by means of a manual device (10) as in any claim hereinbefore.

6. Method as in claim 5, characterized in that said collection of said blood sample (S) occurs with a drop (G) of blood having a volume of a few microliters.

7. Method as in claim 6, characterized in that said collection of said blood sample (S) provides to put one end of a capillary tube (30) in contact with said drop (G) of blood.

8. Method as in claim 5, 6 or 7, characterized in that during said sample collection step, said manual device (10) is oriented horizontally or inclined with respect to the horizontal by an angle not greater than 50°.

9. Method as in any claim from 5 to 8, characterized in that it provides to obtain the result within approximately 8-10 seconds from the collection of the blood sample (S).

10. Method as in any claim from 5 to 9, characterized in that the detection of the ESR is performed through capillary photometry.

11. Method as in any claim from 5 to 10, characterized in that said analysis step provides a stop and flow analysis in a microfluidic channel placed in contact witha drop (G) of blood.

12. Method as in claim 11, characterized in that said stop and flow analysis provides an outflow of the blood sample exclusively through capillary action and a stop of the outflow of the blood sample.

13. Kit for measuring the erythrocyte sedimentation rate, characterized in that it comprises a manual device (10) for measuring the erythrocyte sedimentation rate as in any claim from 1 to 4 and one or more capillary tubes (30) for collecting a blood sample (S).

14. Kit as in claim 13, characterized in that said one or more capillary tubes (30) each comprise, in correspondence with one end thereof, a filter configured to block the outflow of said blood sample (S).

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