Method for discriminating interstitial cystitis

Abstract

The present invention addresses the problem of providing a method for discriminating interstitial cystitis.　The present invention relates to a method for discriminating interstitial cystitis, said method comprising measuring at least one of cholesterol ester (ChE) and lysophosphatidylcholine (LPC) in a urine sample.

Description

How to differentiate interstitial cystitis

[0001] The present invention relates to a method for determining whether or not a patient is suffering from interstitial cystitis based on the amount of cholesterol ester (ChE) and / or lysophosphatidylcholine (LPC) present in urine.

[0002] According to the Clinical Practice Guidelines for Interstitial Cystitis / Bladder Pain Syndrome (Non-Patent Document 1), interstitial cystitis / bladder pain syndrome (IC / BPS) is a general term for "chronic pelvic pain, pressure, or discomfort related to the bladder, accompanied by lower urinary tract symptoms such as increased urinary urge and frequency, in the absence of any other potentially confounding diseases." Interstitial cystitis is also described as "a disease accompanied by nonspecific chronic inflammation of the bladder, presenting with symptoms such as urinary frequency, increased urinary urge, urgency, and bladder pain." Interstitial cystitis is a relatively rare, intractable disease characterized by primary symptoms such as frequent urination, nocturia, increased urinary urge, residual urine, bladder discomfort, and bladder pain. Accompanied by frequent urination and bladder pain, it significantly interferes with daily life. Interstitial cystitis is more prevalent among middle-aged and elderly women, but men and children are also affected.

[0003] Treatment for interstitial cystitis involves medication and dietary therapy, but in severe cases, surgical treatments such as bladder hydrodistension and cystectomy are performed. A reliable diagnosis is a prerequisite for surgical treatment.

[0004] Furthermore, among interstitial cystitis / bladder pain syndrome, those with Hannah lesions are classified as interstitial cystitis (sometimes called IC or Hannah interstitial cystitis), while others are classified as bladder pain syndrome (sometimes called BPS or non-Hannah interstitial cystitis).Hannah lesions are characteristic erosive lesions that, pathologically, differ from ulcers in that they do not have depressions in the lesion area, but are flat or slightly raised, red lesions with relatively clear borders.The presence or absence of the aforementioned Hannah lesions greatly influences the treatment strategy for interstitial cystitis.

[0005] Diagnosis of interstitial cystitis requires confirmation by endoscopy, but endoscopic findings lack objectivity, making it difficult for doctors with extensive experience to make a definitive diagnosis. For this reason, pathological diagnosis, such as tissue findings from biopsies, may also be used to make a definitive diagnosis of interstitial cystitis. For this reason, it can take several years to reach a definitive diagnosis, and even today, there are many patients who are undiagnosed and untreated and are suffering.

[0006] Given the above circumstances, the discovery of a simple diagnostic method for interstitial cystitis (such as a urinary biomarker) would lead to the possibility of early therapeutic intervention, which would be beneficial for both patients and physicians. However, to date, no biomarkers useful for simple diagnosis of this disease have been established, and many patients miss opportunities for early treatment. For example, cytokines and chemokines such as antiproliferative factor (APF) and nerve growth factor (NGF) in urine or serum are considered potential biomarkers for the diagnosis of interstitial cystitis, but they are still insufficient for definitive diagnosis.

[0007] Patent Literature 1 discloses a method for diagnosing interstitial cystitis by detecting a decrease in the amount of a specific lysophosphatidylcholine (LPC) in blood, serum, or plasma in patients with interstitial cystitis. Patent Literature 2 also discloses a method for diagnosing interstitial cystitis by detecting a high level of a specific molecular species of lysophosphatidylcholine (LPC) in a sample derived from the human cerebrospinal cord in patients with interstitial cystitis. However, these diagnostic methods pose a new problem in that they require invasive sample collection, such as blood sampling or cerebrospinal fluid collection. To date, no diagnostic method for interstitial cystitis using a non-invasive sample exists.

[0008] Therefore, there remains a need for a simple method for diagnosing interstitial cystitis using a non-invasive sample.

[0009] Patent No. 6757870 Patent No. 6925610

[0010] "Interstitial Cystitis / Bladder Pain Syndrome Treatment Guidelines," edited by the Japanese Interstitial Cystitis Study Group and the Japanese Urological Association, April 25, 2019, 1st edition, 1st printing, Richhill Medical Co., Ltd., Tokyo

[0011] An object of the present invention is to provide a method for early and simple differentiation of interstitial cystitis, which can use a non-invasive sample.

[0012] The present inventors have conducted extensive research to solve the above problems and have surprisingly found that the levels of cholesterol esters and lysophosphatidylcholine in urine are higher in patients with interstitial cystitis than in those without the disease, thereby completing the present invention.Furthermore, the present inventors have surprisingly found that the levels of cholesterol esters and lysophosphatidylcholine in urine are higher in patients with interstitial cystitis than in patients with bladder pain syndrome, thereby completing the present invention.

[0013] That is, the present invention is as follows: [1] A method for distinguishing whether or not a patient has interstitial cystitis, comprising measuring at least one of cholesterol ester and lysophosphatidylcholine in a urine sample (which may or may not include the act of diagnosing a human by a physician). [2] The method for distinguishing whether or not a patient has interstitial cystitis, comprising measuring both cholesterol ester and lysophosphatidylcholine in a urine sample. [3] The method for distinguishing whether or not a patient has interstitial cystitis, comprising measuring at least one of cholesterol ester and lysophosphatidylcholine in a sample by LC-MS (preferably positive ion detection LC-ESI / MS / MS measurement) using stable isotopes of these esters as internal standards. [4] A biomarker for distinguishing whether or not a patient has interstitial cystitis, characterized by being at least one of cholesterol ester and lysophosphatidylcholine in a urine sample. [5] The biomarker for distinguishing whether or not a patient has interstitial cystitis, characterized by being both cholesterol ester and lysophosphatidylcholine in a urine sample. [6] A kit for diagnosing whether or not a subject is affected with interstitial cystitis, comprising: a means for measuring at least one of cholesterol ester and lysophosphatidylcholine in a urine sample collected from a subject (e.g., a sample collection tool or preparation tool, or a tool or reagent for measuring cholesterol ester and lysophosphatidylcholine), or a means for comparing the obtained measurement value of the subject with the measurement value of at least one of cholesterol ester and lysophosphatidylcholine in a corresponding sample collected from a healthy subject (e.g., a comparison table). [7] A kit for diagnosing whether or not a subject is affected with interstitial cystitis, comprising: a means for measuring at least one of cholesterol ester and lysophosphatidylcholine in a urine sample collected from a subject (e.g., a sample collection tool or preparation tool, or a tool or reagent for measuring cholesterol ester and lysophosphatidylcholine), or a means for comparing the obtained measurement value of the subject with the cutoff value of cholesterol ester and / or lysophosphatidylcholine (e.g., a comparison table).[8] The kit for distinguishing between cholesterol esters and lysophosphatidylcholine according to the above item [6] or [7], wherein both cholesterol esters and lysophosphatidylcholine are measured. [9] A method for measuring at least one of cholesterol esters and lysophosphatidylcholine in a urine sample for the purpose of diagnosing interstitial cystitis.

[10] A method for obtaining data for objective evaluation of interstitial cystitis, comprising measuring at least one of cholesterol esters and lysophosphatidylcholine in a urine sample.

[0014] According to the present invention, urine collected by a non-invasive method can be used as a sample, and it is possible to quickly and simply determine whether or not a patient has interstitial cystitis. Furthermore, according to the present invention, it is also possible to differentiate between interstitial cystitis and bladder pain syndrome, so that it is possible to quickly and simply differentiate between interstitial cystitis without the need to take the time and effort of confirming the presence or absence of Hannah's lesion by biopsy.

[0015] FIG. 1 shows the peak area ratios of urinary ChE (16:0) in BPS, IC, and a healthy female subject. FIG. 2 shows the peak area ratios of urinary ChE (16:1) in BPS, IC, and a healthy female subject. FIG. 3 shows the peak area ratios of urinary ChE (18:0) in BPS, IC, and a healthy female subject. FIG. 4 shows the peak area ratios of urinary ChE (18:1) in BPS, IC, and a healthy female subject. FIG. 5 shows the peak area ratios of urinary ChE (18:2) in BPS, IC, and a healthy female subject. FIG. 6 shows the peak area ratios of urinary ChE (18:3) in BPS, IC, and a healthy female subject. FIG. 7 shows the peak area ratios of urinary ChE (20:4) in BPS, IC, and a healthy female subject. FIG. 8 shows the peak area ratios of urinary ChE (20:5) in BPS, IC, and a healthy female subject. FIG. 1 shows the peak area ratios of ChE (22:6) in the urine of BPS, IC, and a healthy female subject. FIG. 2 shows the peak area ratios of LPC (16:0) sn-1 in the urine of BPS, IC, and a healthy female subject. FIG. 3 shows the peak area ratios of LPC (16:0) sn-2 in the urine of BPS, IC, and a healthy female subject. FIG. 4 shows the peak area ratios of LPC (18:0) sn-1 in the urine of BPS, IC, and a healthy female subject. FIG. 5 shows the peak area ratios of LPC (18:0) sn-2 in the urine of BPS, IC, and a healthy female subject. FIG. 6 shows the peak area ratios of LPC (18:1) sn-1 in the urine of BPS, IC, and a healthy female subject. FIG. 7 shows the peak area ratios of LPC (18:1) sn-2 in the urine of BPS, IC, and a healthy female subject. 1 shows the peak area ratios of urinary LPC (18:2) sn-1 in BPS, IC, and healthy female subjects. 2 shows the peak area ratios of urinary LPC (18:2) sn-2 in BPS, IC, and healthy female subjects. 3 shows the peak area ratios of urinary LPC (20:4) sn-1 in BPS, IC, and healthy female subjects. 4 shows the peak area ratios of urinary LPC (20:4) sn-2 in BPS, IC, and healthy female subjects. 5 shows the peak area ratios of urinary LPC (22:6) sn-1 in BPS, IC, and healthy female subjects. 6 shows the peak area ratios of urinary LPC (22:6) sn-2 in BPS, IC, and healthy female subjects. 7 shows the ROC curves of urinary ChE (16:0) in female IC patients compared to healthy female subjects.FIG. 1 shows the ROC curve of urinary LPC (16:0) sn-1 in female IC patients compared to healthy female subjects. FIG. 2 shows the area ratios of ChE (16:0) in BPS, IC, and healthy male subjects. FIG. 3 shows the area ratios of ChE (16:1) in BPS, IC, and healthy male subjects. FIG. 4 shows the area ratios of ChE (18:0) in BPS, IC, and healthy male subjects. FIG. 5 shows the area ratios of ChE (18:1) in BPS, IC, and healthy male subjects. FIG. 6 shows the area ratios of ChE (18:2) in BPS, IC, and healthy male subjects. FIG. 7 shows the area ratios of ChE (18:3) in BPS, IC, and healthy male subjects. FIG. 8 shows the area ratios of ChE (20:4) in BPS, IC, and healthy male subjects. FIG. 9 shows the area ratios of ChE (20:5) in BPS, IC, and healthy male subjects. FIG. 1 shows the area ratios of ChE (22:6) in BPS, IC, and a healthy male subject. FIG. 2 shows the area ratios of LPC (16:0) sn-1 in BPS, IC, and a healthy male subject. FIG. 3 shows the area ratios of LPC (16:0) sn-2 in BPS, IC, and a healthy male subject. FIG. 4 shows the area ratios of LPC (18:0) sn-1 in BPS, IC, and a healthy male subject. FIG. 5 shows the area ratios of LPC (18:0) sn-2 in BPS, IC, and a healthy male subject. FIG. 6 shows the area ratios of LPC (18:1) sn-1 in BPS, IC, and a healthy male subject. FIG. 7 shows the area ratios of LPC (18:1) sn-2 in BPS, IC, and a healthy male subject. FIG. 8 shows the area ratios of LPC (18:2) sn-1 in BPS, IC, and a healthy male subject. 1 is a diagram showing the area ratios of LPC (18:2) sn-2 in BPS, IC, and healthy male individuals. 2 is a diagram showing the area ratios of LPC (20:4) sn-1 in BPS, IC, and healthy male individuals. 3 is a diagram showing the area ratios of LPC (20:4) sn-2 in BPS, IC, and healthy male individuals. 4 is a diagram showing the area ratios of LPC (22:6) sn-1 in BPS, IC, and healthy male individuals. 5 is a diagram showing the area ratios of LPC (22:6) sn-2 in BPS, IC, and healthy male individuals. 6 is a diagram showing the ROC curves of ChE (16:0) in male IC patients compared to healthy male individuals. 7 is a diagram showing the ROC curves of LPC (16:0) in male IC patients compared to healthy male individuals.

[0016] In the present invention, the amount of at least one of cholesterol ester and lysophosphatidylcholine (hereinafter collectively referred to as "biomarkers of the present invention") in urine collected from interstitial cystitis patients and healthy individuals is higher in interstitial cystitis patients compared to healthy individuals, and therefore, by measuring the biomarkers of the present invention, it is possible to distinguish whether or not a patient has interstitial cystitis. Furthermore, in the present invention, the amount of at least one of the biomarkers of the present invention in urine collected from interstitial cystitis patients is higher compared to patients with bladder pain syndrome, and therefore, by measuring the biomarkers of the present invention, it is possible to distinguish whether or not a patient has interstitial cystitis.

[0017] Specifically, for example, at least one of the biomarkers of the present invention is measured in urine collected from a subject and a healthy individual or a patient with bladder pain syndrome to be differentiated, and the measurement value obtained for the subject is compared with the measurement value for the healthy individual or the patient with bladder pain syndrome, thereby making it possible to differentiate whether or not the subject is suffering from interstitial cystitis.

[0018] The present invention may be applied to the diagnosis of interstitial cystitis by taking multiple measurements and performing a statistical analysis. For example, if the measured value of a subject is significantly higher than those of healthy individuals or patients with bladder pain syndrome, the subject can be diagnosed as suffering from interstitial cystitis.

[0019] Alternatively, a cutoff value may be set and interstitial cystitis may be differentiated by comparing the obtained measurement value of the subject with the cutoff value. The cutoff value refers to the value above which the subject is identified as suffering from interstitial cystitis when the measurement value of ChE and / or LPC in the subject's urine exceeds the cutoff value. The cutoff value varies depending on the animal species. Alternatively, cutoff values ​​can be set for each molecular species of ChE and LPC. For example, cutoff values ​​can be set for each molecular species for men and women as shown in Table 1 below.

[0020]

[0021] The cutoff value can be calculated based on, for example, a receiver operating characteristic (ROC) curve.

[0022] In the present invention, differentiation is possible by measuring and comparing at least one of cholesterol esters and lysophosphatidylcholine, but it is particularly preferable to measure and compare cholesterol esters. Furthermore, in the present invention, it is preferable to measure and compare both cholesterol esters and lysophosphatidylcholine, as this improves the accuracy and precision of differentiation.

[0023] The cholesterol esters of the biomarkers of the present invention are formed by esterification of cholesterol and fatty acids. They have various structures depending on the carbon chain length of the fatty acid moiety, the presence and number of unsaturated bonds, etc., but are collectively referred to herein as "cholesterol esters." The cholesterol esters of the present invention are preferably cholesterol esters having long-chain fatty acids, more preferably cholesterol esters having fatty acids with 12 to 20 carbon atoms, and particularly preferred are cholesterol esters having fatty acids with 16 to 18, 18 to 20, and 18 to 22 carbon atoms. Furthermore, any molecular species of cholesterol esters, such as 16:0, 16:1, 18:0, 18:1, 18:2, 18:3, 20:3, 20:4, 20:5, and 22:6, can be measured. From the standpoint of accuracy and precision of differentiation, 16:0, 16:1, 18:0, 18:1, 18:2, 18:3, 20:4, 20:5, and 22:6 are preferably measured.

[0024] The lysophosphatidylcholine biomarker of the present invention refers to a phosphatidylcholine having only one fatty acid bound thereto, and any molecular species, such as 16:0, 16:1, 18:0, 18:1, 18:2, 20:4, and 22:6, can be measured. From the viewpoint of differentiation accuracy and precision, it is preferable to measure 16:0, 18:0, 18:1, 18:2, 20:4, and 22:6.

[0025] In the differentiation method of the present invention, "subject" refers to animals including humans, "healthy individual" refers to animals including humans who are not undergoing treatment for interstitial cystitis, "bladder pain syndrome patient" refers to animals including humans who have been diagnosed by a doctor or veterinarian as suffering from bladder pain syndrome, also known as non-Hannah interstitial cystitis, and "interstitial cystitis patient" refers to animals including humans who have been diagnosed by a doctor or veterinarian as suffering from interstitial cystitis.

[0026] Examples of non-human animals include pets such as dogs, cats, and parakeets, livestock such as cows, pigs, and horses, and poultry such as chickens.

[0027] In the present invention, when comparing measured values ​​of a subject, a healthy individual, a patient with bladder pain syndrome, and a patient with interstitial cystitis, or when comparing measured values ​​of a subject with a cutoff value, it is preferable that these values ​​are measured in at least the same animal species, and that conditions such as subspecies (including race), sex, age (including age in months and weeks), height, and weight are also the same.

[0028] The "sample" in which the biomarkers of the present invention are measured is urine, which is advantageous in that it can be collected non-invasively from subjects, healthy individuals, patients with bladder pain syndrome, and patients with interstitial cystitis. However, urine collected by catheterization or cystocentesis may also be used in the present invention. Furthermore, as the "urine sample" of the present invention, collected urine may be used as is, or pretreated urine, such as a supernatant obtained by centrifugation or a filtrate obtained by filtration, may also be used.

[0029] In the present invention, the method for measuring the biomarker of the present invention is not particularly limited as long as it can measure cholesterol esters and / or lysophosphatidylcholine in urine, and any conventional measurement method can be used. For example, conventional colorimetric methods, radioimmunoassays (RIA), and liquid chromatography-mass spectrometry (LC-MS) can be used. Other immunological methods that can be used include chemiluminescent enzyme immunoassays (CLEIA), enzyme-linked immunosorbent assays (ELISA), and electrochemiluminescent immunoassays (ECLIA).

[0030] Liquid chromatography-mass spectrometry (LC-MS) is preferred because it is simple and does not require the use of radioactive materials or derivatization, and has a wide quantification range, allowing the use of stable isotopes as internal standards (IS). LC-MS refers to an analytical method performed using an apparatus that combines a liquid chromatograph and a mass spectrometer. Examples include liquid chromatography tandem mass spectrometry (LC-MS / MS) and liquid chromatography time-of-flight mass spectrometry (LC-TOF-MS), with LC-MS / MS being preferred. Mass spectrometry requires ionization of the target component. Examples of ionization methods include atmospheric pressure chemical ionization (APCI), electrospray ionization (ESI), and atmospheric pressure photoionization (APPI). Combining these ionization methods with LC-MS / MS, techniques such as Liquid Chromatography-Electrospray ionization-based Tandem Mass Spectrometry (LC-ESI / MS / MS) and Liquid Chromatography-Atmospheric pressure chemical ionization-based Tandem Mass Spectrometry (LC-APCI / MS / MS) are used. These measurements can be performed using standard methods. LC-ESI / MS / MS is preferred for this measurement. Ion detection can be either positive ion detection or negative ion detection, and positive ion detection is preferred for this measurement.

[0031] Furthermore, the mass analysis section may be, for example, a magnetic field type, a quadrupole type, a time-of-flight type, or an ion trap type, but in the present invention, it is preferable to use a quadrupole type, which has good quantitative performance, a wide dynamic range, and good linearity.

[0032] Further, methods for detecting ions in quantification include selected ion monitoring, which selectively detects only the ions of interest, and selected reaction monitoring (SRM), which selects one of the ion species generated in the first mass analyzer as a precursor ion and detects product ions generated by the fragmentation of that precursor ion in the second mass analyzer. In the present invention, measurement using SRM is preferred because it increases selectivity and reduces noise, thereby improving the signal-to-noise ratio.

[0033] Stable isotopes of cholesterol esters and lysophosphatidylcholine are commercially available or can be synthesized by conventional methods. Since the target of measurement in the differentiation method of the present invention is cholesterol esters and lysophosphatidylcholine, the above-mentioned positive ion detection LC-ESI / MS / MS measurement method can be used, and the method is advantageous in that it can easily and accurately differentiate interstitial cystitis.

[0034] The present invention also relates to a method of using cholesterol ester or lysophosphatidylcholine, preferably both, as a biomarker for distinguishing whether or not a patient has interstitial cystitis, particularly Hanna-type interstitial cystitis.

[0035] The present invention also relates to a differentiation kit for use in the differentiation method of the present invention. The kit used for the differentiation method of the present invention can include at least one selected from a buffer solution, an acid, a base, alcohol, a syringe, an antibody, and a document describing the measurement procedure. In addition, the kit used for the differentiation method of the present invention can further include a document describing the evaluation criteria.

[0036] More specifically, the "discrimination kit" of the present invention comprises means necessary for distinguishing whether or not a subject has interstitial cystitis by comparing the measured value of at least one biomarker of the present invention in a urine sample collected from the subject with the corresponding measured value or cut-off value of at least one biomarker of the present invention in corresponding samples collected from healthy subjects and interstitial cystitis patients. For example, means for measuring at least one biomarker of the present invention present in a urine sample collected from the subject may include a sample collection tool or preparation tool, or a measurement tool or reagent for cholesterol ester and / or lysophosphatidylcholine, such as a column cartridge. Furthermore, means for comparing the measured value of at least one biomarker of the present invention in a urine sample collected from the subject with the corresponding measured value or cut-off value of at least one biomarker of the present invention in corresponding samples collected from healthy subjects and interstitial cystitis patients may include a comparison table of measured values ​​or cut-off values ​​for healthy subjects and interstitial cystitis patients, respectively. Among these, the comparison table is particularly useful because it allows differentiation of target diseases without relying on the judgment of a doctor.

[0037] The present invention also relates to a method for measuring at least one, preferably both, of cholesterol esters and lysophosphatidylcholine in a urine sample for the purpose of diagnosing interstitial cystitis, and a method for obtaining data for objectively evaluating interstitial cystitis, which comprises measuring at least one, preferably both, of cholesterol esters and lysophosphatidylcholine in a urine sample.The present invention also relates to a method for screening for therapeutic or preventive agents for interstitial cystitis, which comprises measuring at least one, preferably both, of cholesterol esters and lysophosphatidylcholine in a sample.

[0038] The present invention will be described in detail below with reference to examples, but the present invention is not limited to the following examples. The devices and materials used in the examples are as follows.

[0039] Example 1: Differentiation of Interstitial Cystitis 1. Preparation of Samples Containing Cholesterol Esters and Lysophosphatidylcholine 5 μL of internal standard solution (2.5 μg / mL cholesterol ester (22:4)-d7 and lysophosphatidylcholine (19:0)-d7 mixed methanol solution) was collected in a glass test tube, and 1.2 mL of urine sample was then collected. 3 mL of methanol and 1.5 mL of chloroform were added to each test tube, stirred, and allowed to stand for 10 minutes. 1.5 mL of chloroform was then added, stirred, and allowed to stand for 10 minutes. 0.63 mL of water and 0.87 mL of 1 M acetic acid were added sequentially and stirred. After centrifuging the sample, the upper layer was discarded and the lower layer was collected in a glass test tube. The solvent was removed using a centrifugal evaporator, and methanol was added and stirred. After centrifugation, the supernatant was collected and used as the pretreated sample.

[0040] 2. LC-MS and analytical conditions: The samples prepared above were analyzed by high-resolution, accurate mass LC-MS. An Acclaim 120 C18 (150 mm x 2.1 mm, 3 μm) column was used for HPLC (mobile phase: 5 mM formic acid and 0.1% ammonium formate in water / acetonitrile / methanol (2:1:1) mixture and 5 mM formic acid and 0.1% ammonium formate in acetonitrile / isopropanol (1:9) mixture. After gradient separation, the lipids were ionized using an electron spray ionization probe and comprehensively analyzed using a Q-Exactive Orbitrap / MS. Peak areas of the comprehensively analyzed lipids were calculated using the analysis software Xcalibur and Lipid Search 4.

[0041] 3. Measurement of cholesterol esters and lysophosphatidylcholine According to the LC-MS method for measuring urinary lipids of the present invention, the peak areas of each molecular species of cholesterol esters and lysophosphatidylcholine in the urine of patients with bladder pain syndrome (BPS), patients with interstitial cystitis (IC), and healthy individuals were calculated as shown in Table 2. The peak areas were corrected using the peak areas of the internal standard (cholesterol ester (22:4)-d7 or lysophosphatidylcholine (19:0)-d7) and urinary creatinine, and the peak area ratios were calculated.

[0042]

[0043] The peak area ratios of urinary lipids in women and men are shown as box plots (Figures 1 to 21 and Figures 24 to 44, respectively). In addition, the results of comparing ChE and LPC molecular species in patients with interstitial cystitis with those in healthy subjects are shown in Tables 3 to 6.

[0044]

[0045]

[0046]

[0047]

[0048] These results demonstrate that the peak area ratios of urinary cholesterol esters were elevated in both female and male patients with interstitial cystitis compared with healthy controls and patients with bladder pain syndrome, with significant increases in all molecular species measured compared with healthy controls (P<0.001). Furthermore, the peak area ratios of urinary lysophosphatidylcholine were elevated in both female and male patients with interstitial cystitis compared with healthy controls and patients with bladder pain syndrome, with significant increases in all molecular species measured compared with healthy controls (P<0.001). Thus, urinary cholesterol esters are an effective biomarker for distinguishing patients with interstitial cystitis from healthy controls and patients with bladder pain syndrome, and differentiation is possible based on cholesterol esters alone. Furthermore, urinary lysophosphatidylcholine, like cholesterol esters, is also a useful biomarker for interstitial cystitis, and although differentiation is possible based on urinary lysophosphatidylcholine alone, the accuracy of differentiation is improved by combining cholesterol esters with lysophosphatidylcholine.

[0049] For the peak area ratios of urinary ChE and LPC molecular species, the areas under the ROC curves, cutoff values, sensitivity, specificity, and likelihood ratios for female IC patients compared to healthy women are shown in Tables 7 and 8. Parts of the ROC curves are also shown in Figures 22 and 23.

[0050]

[0051]

[0052] For the peak area ratio, the area under the ROC curve, cutoff value, sensitivity, specificity, and likelihood ratio for male IC patients relative to healthy males were calculated. The results are shown in Tables 9 and 10. Parts of the ROC curves are shown in Figures 45 and 46.

[0053]

[0054]

[0055] According to the differentiation method of the present invention, differentiation of interstitial cystitis can be performed by measuring at least one of cholesterol ester and lysophosphatidylcholine in a urine sample. Furthermore, cholesterol ester and lysophosphatidylcholine can be used as biomarkers for diagnosing or differentiating interstitial cystitis. The present invention can be used, for example, in the fields of medicine and pharmacy. For example, measuring at least one of cholesterol ester and lysophosphatidylcholine in a urine sample can contribute to the diagnosis of interstitial cystitis, and the measured values ​​can be used as data for objective evaluation of interstitial cystitis, for example, to support and assist the diagnosis of interstitial cystitis.

Claims

1. A method for determining whether or not a person is suffering from interstitial cystitis, comprising measuring at least one of cholesterol ester and lysophosphatidylcholine in a urine sample (excluding the act of diagnosing a human by a physician).

2. The method according to claim 1, wherein both cholesterol esters and lysophosphatidylcholine are measured.

3. A method for distinguishing between cholesterol esters and lysophosphatidylcholine according to claim 1 or 2, wherein the measurement of at least one of cholesterol esters and lysophosphatidylcholine in a sample is carried out by LC-MS using stable isotopes of these substances as internal standards.

4. A biomarker for distinguishing whether or not a person is affected by interstitial cystitis, characterized in that the biomarker is at least one of cholesterol ester and lysophosphatidylcholine in a urine sample.

5. The biomarker according to claim 4, characterized in that it is both a cholesterol ester and a lysophosphatidylcholine.

6. A kit for diagnosing whether or not a subject is suffering from interstitial cystitis, comprising a means for measuring at least one of cholesterol esters and lysophosphatidylcholine in a urine sample collected from the subject, or a means for comparing the obtained measurement value of the subject with the measurement value of at least one of cholesterol esters and lysophosphatidylcholine in a corresponding sample collected from a healthy subject.

7. A kit for diagnosing whether or not a subject is suffering from interstitial cystitis, comprising a means for measuring at least one of cholesterol esters and lysophosphatidylcholine in a urine sample collected from the subject, or a means for comparing the obtained measurement value of the subject with a cutoff value for cholesterol esters and / or lysophosphatidylcholine.

8. The identification kit according to claim 6 or 7, wherein both cholesterol esters and lysophosphatidylcholine are measured.

9. A method for measuring at least one of cholesterol ester and lysophosphatidylcholine in a urine sample for the purpose of diagnosing interstitial cystitis.

10. A method for obtaining data for the objective evaluation of interstitial cystitis, comprising measuring at least one of cholesterol ester and lysophosphatidylcholine in a urine sample.

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