The value of fecal calprotectin measured by fluorescent immunochromatography assay in evaluating clinical and endoscopic activity in ulcerative colitis

The value of fecal calprotectin measured by fluorescent immunochromatography assay in evaluating clinical and endoscopic activity in ulcerative colitis | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article The value of fecal calprotectin measured by fluorescent immunochromatography assay in evaluating clinical and endoscopic activity in ulcerative colitis Mingyang Xu, Junrong Li, Lei Tu, Wei Qian, Fangmei Ling, Yidong Chen, and 4 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-4221555/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Aim: Fecal calprotectin (FC) levels correlate with clinical or endoscopic activity in ulcerative colitis (UC), however, these values vary widely between detection methods, and optimal cut-off values remain debated. To assess the correlation between FC levels measured by fluorescent immunochromatography assay (FICA) and disease activity and to identify optimal cut-off values for predicting clinical and endoscopic activity in UC. Method: Patients reviewed were hospitalized at Union Hospital, Tongji Medical College, Huazhong University of Science and Technology between January 2021 and June 2022. All the patients had a confirmed diagnosis of UC. Clinical activity was determined using the partial Mayo score (pMS), and endoscopic activity was determined using the ulcerative colitis endoscopy index of severity (UCEIS) and Mayo endoscopic score (MES). Results: In 109 patients with UC, FC levels were significantly correlated with pMS (r = 0.606, P <0.001), UCEIS (r = 0.753, P <0.001) and MES (r = 0.642, P <0.001). Moreover, the optimal FC cut-off values to predict clinical activity (pMS 3-12) and endoscopic activity (UCEIS 1-8 or MES 1-3) were 57.38 μg/g and 53.30 μg/g, respectively. Conclusion: FC measured by FICA was a good predictor of clinical and endoscopic activity in patients with UC. When using FICA to detect FC, the optimal cut-off value to identify clinical activity in patients with UC was 57.38 μg/g, and a lower value should be chosen to optimize the identification of endoscopic activity in these patients, which was determined as 53.30 μg/g. fecal calprotectin ulcerative colitis clinical activity endoscopic activity cut-off value Figures Figure 1 Figure 2 Introduction Ulcerative colitis (UC) is a subtype of inflammatory bowel disease (IBD), characterized by mucosal ulceration. Generally, it starts in the rectum and can extend continuously and proximally to the entire colon 1 . The Montreal classification of the extent of UC is divided into three subgroups: E1 (ulcerative proctitis), E2 (left-sided UC) and E3 (extensive UC) 2 . The clinical course of UC is characterized by alternating periods of remissions and relapses 1 . To avoid disease progression, regular colonoscopy is necessary, as it remains the gold standard for monitoring endoscopic activity 3 . However, colonoscopy is an invasive and inconvenient procedure. Therefore, serum biomarkers have been explored as indicators of intestinal inflammation in patients with IBD. C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) are widely used to monitor inflammation flareups 4 , 5 . However, they are elevated in many inflammatory diseases and poorly correlated with intestinal diseases 6 . Fecal biomarkers, on the other hand, can compensate for these deficiencies. They are more specific to intestinal inflammation 7 . Calprotectin is primarily derived from neutrophils 8 . Since it can be detected in stools, there is a large amount of evidence suggesting that fecal calprotectin (FC) levels correlate well with the activity of intestinal diseases 9 , 10 . Currently, it is the most commonly used fecal biomarker for the diagnosis and management of IBD, which helps reduce the frequency of colonoscopy 7 , 11 – 13 . However, there are still some limitations to using FC in predicting disease activity. As detection methods of FC testing have not been standardized and results vary widely between different methods 14 , there remains no consensus on the optimal cut-off values to define active UC 15 . Fluorescent immunochromatography assay (FICA) is a method that allows for rapid detection of FC, and there are few reports on its use for detecting FC and almost none on the optimal FC cut-off values for this method. To define the optimal FC cut-off values measured by FICA would help us to better manage patients with UC. Therefore, the study aimed to assess the correlation between FC levels and disease activity and identify optimal cut-off values for predicting clinical and endoscopic activity in UC using a detection method based on FICA instead of enzyme-linked immunosorbent assay (ELISA). Methods Patients The patients reviewed were those hospitalized at Union Hospital, Tongji Medical College, Huazhong University of Science and Technology between January 2021 and June 2022. They were diagnosed with UC based on clinical, endoscopic and histologic features. All patients underwent FC testing at the time of colonoscopy. FC testing FC was detected using the calprotectin FICA kit (Wiz Biotech, Xiamen, China) and WIZ-A202 continuous immunoassay analyzer (Wiz Biotech, Xiamen, China). The operation procedure was carried out strictly according to the kit and instrument instructions. Operation procedure: 50 mg of the stool sample was taken into one sample diluent using the sampling stick in the kit, 80 µL of the diluted sample was added into the well of the test card after mixing, and then the test card was put into the continuous immunoassay analyzer, and the result could be read after 15 minutes. The results were in µg/g, with a minimum of 10.00 µg/g. All samples were collected within 1 week prior to the examination and tested within 24 hours of delivery. Measures of clinical and endoscopic activity The clinical activity was determined using the partial Mayo score (pMS), whereas endoscopic activity was determined using the ulcerative colitis endoscopy index of severity (UCEIS) and Mayo endoscopic score (MES) 16 , 17 . Clinical remission was defined as pMS 1, with mild activity defined as pMS 3–5, moderate activity as pMS 6–10 and severe activity as pMS 11–12. Endoscopic remission was defined as UCEIS = 0 or MES = 0, mild activity as UCEIS 1–3 or MES = 1, moderate activity as UCEIS 4–6 or MES = 2 and severe activity as UCEIS 7–8 or MES = 3. Statistical analyses Categorical variables were presented as numbers (n) and percentages (%), and continuous variables were presented as mean ± standard deviation (SD) or median with interquartile range (IQR). The Kolmogorov-Smirnov test was used to evaluate whether continuous variables followed a normal distribution. The Mann-Whitney U test was used to compare two continuous variables, and Spearman’s correlation was used to estimate the association between the parameters. A receiver operating characteristic (ROC) curve analysis with 95% confidence intervals (95% CI) was used to evaluate the performance of FC, CRP and ESR in predicting clinical and endoscopic activity. Youden’s j statistic were calculated for different cut-off values. Statistical analyses were performed using SPSS v 26.0 (IBM, Armonk, New York), and figures were drawn using GraphPad Prism 9 (GraphPad Software, San Diego, California). P- values < 0.05 were considered statistically significant, and all P- values were two-tailed. Results Patient characteristics A total of 109 patients with UC were reviewed, including 58.72% males (n = 64) and 41.28% females (n = 45), with a mean age of 43.96 ± 13.87 years, median disease duration of 18 (IQR, 6, 48) months and median body mass index of 22.05 (IQR, 19.30, 24.42) kg/m 2 . FC levels of these patients ranged from 10.00 to 731.01 µg/g, with a median of 78.37 µg/g (IQR, 45.69, 132.34). (See Table 1 for detailed data). Table 1 Patient Characteristics (n = 110) Characteristics Number Male, n (%) 64 (58.72) Female, n (%) 45 (41.28) Age at diagnosis, years, mean (SD) 43.96 (13.87) Disease duration, months, median (IQR) 18 (6, 48) BMI, median (IQR) 22.05 (19.30, 24.42) Montreal classification, n (%) E1 11 (10.09) E2 32 (29.36) E3 66 (60.55) Primary symptoms, n (%) Hematochezia 92 (85.19) Diarrhea 56 (51.85) Abdominal pain 41 (37.96) Smoking, n (%) Never 95 (87.16) Former 11 (10.09) Current 3 (2.75) Total proctocolectomy, n (%) Yes 0 (0.00) No 109 (100.00) Medications, n (%) 5-ASA 87 (79.82) Corticosteroids 29 (26.61) Tumor necrosis factor inhibitor 16 (14.68) Vedolizumab 11 (10.09) Immunomodulators 3 (2.75) Laboratory testing, median (IQR) FC (µg/g) 78.37 (45.69, 132.34) CRP (mg/L) 3.34 (3.34, 10.90) ESR (mm/h) 10.00 (5.00, 21.50) Hemoglobin (g/L) 121.00 (106.00, 135.00) Platelets (×10 9 /L) 259.00 (202.00, 326.00) WBC (×10 9 /L) 5.97 (4.79, 7.74) NEUT% (%) 60.50 (52.00, 68.03) Albumin (g/L) 40.10 (36.55, 43.75) Clinical activity, n (%) pMS < 3 19 (17.43) pMS 3–5 22 (20.18) pMS 6–10 53 (48.62) pMS 11–12 15 (13.76) Endoscopic activity (UCEIS), n (%) UCEIS = 0 8 (7.34) UCEIS 1–3 32 (29.36) UCEIS 4–6 53 (48.62) UCEIS 7–8 16 (14.68) Endoscopic activity (MES), n (%) MES = 0 11 (10.09) MES = 1 14 (12.84) MES = 2 47 (43.12) MES = 3 37 (33.94) SD, standard deviation; IQR, interquartile range; 5-ASA, 5-Amino Salicylic Acid; FC, fecal calprotectin; CRP, C-reactive protein; ESR, erythrocyte sedimentation rate; WBC, White blood cell; NEUT%, neutrophil count percentage; pMS, partial Mayo score; UCEIS, ulcerative colitis endoscopy index of severity; MES, Mayo Endoscopic Score Significant differences in FC levels between remission and active disease groups The distributions of FC levels according to the pMS, UCEIS and MES were presented in Fig. 1 A-C, respectively. The FC levels were compared between the remission and active disease groups and between different subgroups of active disease. There were significant differences in FC levels between the remission and active disease groups and between the mildly active and moderately active disease groups based on pMS, UCEIS or MES (Fig. 1 A-F). The FC levels in the severely active disease groups were significantly higher than those in the moderately active disease groups. In contrast, there was no difference in the FC levels between the clinically severely active and moderately active disease groups. Better correlations of FC levels with clinical and endoscopic activity The FC levels had high and statistically significant correlations with pMS, UCEIS and MES and were superior to CRP and ESR. The FC levels correlated better with endoscopic activity than with clinical activity. (See Table 2 for detailed data). Table 2 Correlations of FC, CRP and ESR levels with disease activity pMS UCEIS MES r P r P r P FC 0.606 < 0.001 0.753 < 0.001 0.642 < 0.001 CRP 0.419 < 0.001 0.521 < 0.001 0.380 < 0.001 ESR 0.284 0.004 0.281 0.004 0.192 0.053 FC, fecal calprotectin; CRP, C-reactive protein; ESR, erythrocyte sedimentation rate; pMS, partial Mayo score; UCEIS, ulcerative colitis endoscopy index of severity; MES, Mayo endoscopic score Moreover, the correlations between FC levels and disease activity may be influenced by the extent of the disease. The FC levels for E1 correlated the best with disease activity, followed by E2 and E3. (See Table 3 for detailed data). Table 3 Correlations of FC levels with disease activity in different disease extents pMS UCEIS MES r P r P r P E1 0.716 0.013 0.833 0.001 0.678 0.022 E2 0.664 0.001 0.719 < 0.001 0.621 < 0.001 E3 0.485 < 0.001 0.657 < 0.001 0.564 < 0.001 FC, fecal calprotectin; E1, ulcerative proctitis; E2, left-sided ulcerative colitis; E3, extensive ulcerative colitis; pMS, partial Mayo score; UCEIS, ulcerative colitis endoscopy index of severity; MES, Mayo endoscopic score FC levels of patients with clinical remission but no endoscopic remission In clinical practice, there is a discrepancy between clinical activity and endoscopic activity in some patients with UC. In our study, 11 patients had clinical remission but no endoscopic remission. These patients had FC levels ranging from 10.00 to 55.65 µg/g with a median of 22.28 (IQR, 10.97, 39.27) µg/g, pMS ranging from 0 to 2, UCEIS ranging from 1 to 4 and MES ranging from 0 to 1. (See Table 4 for detailed data). Table 4 FC levels of patients with clinical remission but no endoscopic remission FC levels (µg/g) pMS UCEIS MES Patient 1 10.00 0 0 Patient 2 10.00 1 1 Patient 3 10.00 2 1 1 Patient 4 11.94 1 2 1 Patient 5 14.19 1 1 1 Patient 6 22.28 2 0 Patient 7 28.37 2 2 1 Patient 8 33.34 2 3 1 Patient 9 45.19 2 4 1 Patient 10 51.87 1 1 0 Patient 11 55.65 0 2 1 FC, fecal calprotectin; pMS, partial Mayo score; UCEIS, ulcerative colitis endoscopy index of severity; MES, Mayo endoscopic score Optimal FC cut-off values The area under the curve (AUC) in the ROC curve analysis of FC levels to predict pMS 3–12 was 0.9450 (95% CI, 0.8998 to 0.9903; P < 0.0001), which was superior to CRP 0.6954 (95% CI, 0.5829 to 0.8079; P = 0.0078) and ESR 0.6225 (95% CI, 0.4724 to 0.7725; P = 0.1210) (Fig. 2 A). To predict UCEIS 1–8, the AUC in the ROC curve analysis of FC levels was 0.9066 (95% CI, 0.8244 to 0.9887; P = 0.0001), followed by CRP 0.7245 (95% CI, 0.5953 to 0.8537; P = 0.0353) and ESR 0.7598 (95% CI, 0.5949 to 0.9247; P = 0.0508) (Fig. 2 B). To predict MES 1–3, the AUC in the ROC curve analysis of FC levels was 0.9109 (95% CI, 0.8392 to 0.9827; P < 0.0001), followed by CRP 0.7316 (95% CI, 0.6178 to 0.8454; P = 0.0122) and ESR 0.6922 (95% CI, 0.5241 to 0.8603; P = 0.0721) (Fig. 2 C). The optimal FC cut-off values to identify active UC were presented in Table 5 . Table 5 Optimal FC cut-off values pMS 3–12 UCEIS 1–8 MES 1–3 Cut-off value (µg/g) ≥ 57.38 ≥ 53.30 ≥ 53.30 Sensitivity (%) 77.78 71.29 73.47 Specificity (%) 100 100 100 FC, fecal calprotectin; pMS, partial Mayo score; UCEIS, ulcerative colitis endoscopy index of severity; MES, Mayo endoscopic score Discussion FC, an effective non-invasive biomarker of inflammation in the colon, has been used as a companion tool for diagnosing, monitoring and treating UC for several years 10 , 18 . However, the optimal cut-off values of FC for predicting disease activity in UC are still debated. Studies have suggested using values ≥ 121 µg/g or even higher to predict endoscopic activity 19 , 20 , which did not work in our cases. In our study, 54.13% (n = 59) of patients with UCEIS scores of 1–8 had FC levels below 100 µg/g. Therefore, we analyzed the correlation between FC levels and disease activity and redefined the optimal cut-off values. Consistent with previous findings 10 , 18 , our study demonstrated that FC levels correlated well with clinical and endoscopic activity in UC and were superior to CRP and ESR. We found that, compared to clinical activity, FC levels had a higher correlation with endoscopic activity, especially with UCEIS. This may be due to the ability of the UCEIS to distinguish endoscopic activity in greater detail 21 . The optimal FC cut-off value to identify clinical activity (pMS 3–12) was determined as 57.38 µg/g in patients with UC. To identify endoscopic activity (UCEIS 1–8 or MES 1–3), a lower value should be chosen, which was determined as 53.30 µg/g. These values were significantly lower than those previously reported, probably because we used FICA rather than ELISA to detect FC 14 . As the most widely used method currently, ELISA is the standard quantitative test for detecting FC, however, it is expensive and time-consuming 22 . FICA, a valid alternative to ELISA 15 , is easier and faster to perform, and its results have been reported to correlate highly with ELISA results 23 . Through ROC curve analysis, we confirmed that FICA-based FC testing was better at predicting clinical and endoscopic activity in UC than CRP and ESR. According to STRIDE-II, endoscopic healing (UCEIS ≤ 1 or MES = 0) is the long-term target for UC 20 . In our study, some patients with UC had a discrepancy between clinical activity and endoscopic activity. These patients were with clinical remission but had mild endoscopic activity. Their FC levels ranged from 10.00 to 55.65 µg/g, with 10 patients (90.91%) having FC levels below 53.30 µg/g. This suggested that in some patients with UC, even though their FC levels were within the normal range, they may not have achieved endoscopic healing. Our study showed that this group of patients usually did not have severe endoscopic activity, and their endoscopic findings were mainly erythema and/or decreased vascular pattern. However, it still suggested that although FC is an effective biomarker of clinical and endoscopic activity in UC, colonoscopy remains the gold standard for determining endoscopic activity, and FC could play an adjunctive role to reduce the frequency of colonoscopy. Moreover, the extent of UC probably impacted the reliability of FC in predicting disease activity. We analyzed the correlation between FC levels and disease activity in patients with UC with different disease extents. It was observed that FC levels for patients with E1 had the highest correlation with disease activity, followed by E2 and E3. The small sample size may have influenced our findings. Specifically, the sample size of the patients with E1 was relatively small. However, our observation has been suggested that different subgroups of UC may require different cut-off values. Further confirmation would require studies with larger sample sizes. The pre-analytical phase of FC is also very important, especially stool sampling procedure, which could influence FC measurement 22 , 24 . In our study, some patients with pMS 11–12 had FC levels below 100 µg/g, probably due to severe diarrhea, making the sampling procedure substandard. As a fecal biomarker, FC has the advantages of being non-invasive and more specific for intestinal inflammation than serum biomarkers, such as CRP and ESR. However, the lack of standardization of the sampling procedure is a limitation. Preference should be given to patients with normally formed stools from the first bowel movement in the morning 24 . In summary, our results showed that FC was a good predictor of clinical and endoscopic activity in patients with UC. However, stool sampling needed to be standardized. When using FICA to detect FC, 57.38 µg/g and 53.30 µg/g should be chosen to identify patients with UC with clinical and endoscopic activity, respectively. Declarations Ethics statement This study was reviewed and approved by the Ethics Committee of Union Hospital, Tongji Medical College, Huazhong University of Science and Technology (Approval Number: 20220827). It was confirmed that informed consent was obtained from all subjects and/or their legal guardian(s) and that all methods were performed in accordance with the relevant guidelines and regulations. Author contributions Mingyang Xu and Junrong Li contributed equally to this study. Mingyang Xu collected and analyzed the data and drafted and revised the manuscript. Junrong Li helped with data collection and analysis. Wei Qian provided the test results for the FC. Lei Tu, Fangmei Ling, Yidong Chen, Shuang Li and Yiyu Cheng participated in the revision of the manuscript. Huan Wang and Liangru Zhu designed the study, checked the data and analysis results and made the final revisions to the manuscript. All the authors approved the final version of the manuscript. Funding This study was supported by the National Natural Science Foundation of China (82170547 and 81873558). Conflict of interest There was no conflict of interest to declare. Data availability The datasets used and/or analysed during the current study available from the corresponding author on reasonable request. References Ungaro R, Mehandru S, Allen PB, et al. Ulcerative colitis. Lancet. 2017 Apr 29;389(10080):1756-1770. doi: 10.1016/S0140-6736(16)32126-2 Satsangi J, Silverberg MS, Vermeire S, et al. The Montreal classification of inflammatory bowel disease: controversies, consensus, and implications. Gut. 2006 Jun;55(6):749-53. doi: 10.1136/gut.2005.082909 Lamb CA, Kennedy NA, Raine T, et al. 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Gastroenterology. 2021 Apr;160(5):1570-1583. doi: 10.1053/j.gastro.2020.12.031 Arai M, Naganuma M, Sugimoto S, et al. The Ulcerative Colitis Endoscopic Index of Severity is Useful to Predict Medium- to Long-Term Prognosis in Ulcerative Colitis Patients with Clinical Remission. J Crohns Colitis. 2016 Nov;10(11):1303-1309. doi: 10.1093/ecco-jcc/jjw104 D’Amico F, Nancey S, Danese S, et al. A Practical Guide for Faecal Calprotectin Measurement: Myths and Realities. J Crohns Colitis. 2021 Jan 13;15(1):152-161. doi: 10.1093/ecco-jcc/jjaa093 Li R, Zhao X, Dong J, et al. Evaluation of a fluorescent immunochromatography test for fecal calprotectin. J Clin Lab Anal. 2020 Feb;34(2):e23059. doi: 10.1002/jcla.23059 Lasson A, Stotzer PO, Öhman L, et al. The intra-individual variability of faecal calprotectin: a prospective study in patients with active ulcerative colitis. J Crohns Colitis. 2015 Jan;9(1):26-32. doi: 10.1016/j.crohns.2014.06.002 Additional Declarations No competing interests reported. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-4221555","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":288313038,"identity":"c1229e81-63f4-4328-9ec8-e5ff48f27aad","order_by":0,"name":"Mingyang Xu","email":"","orcid":"","institution":"Huazhong University of Science and Technology","correspondingAuthor":false,"prefix":"","firstName":"Mingyang","middleName":"","lastName":"Xu","suffix":""},{"id":288313039,"identity":"9f534371-ac01-4f81-8ec5-5905c62544a4","order_by":1,"name":"Junrong Li","email":"","orcid":"","institution":"Huazhong University of Science and Technology","correspondingAuthor":false,"prefix":"","firstName":"Junrong","middleName":"","lastName":"Li","suffix":""},{"id":288313040,"identity":"07b2e63e-2901-4552-9740-78f496b794d2","order_by":2,"name":"Lei Tu","email":"","orcid":"","institution":"Huazhong University of Science and Technology","correspondingAuthor":false,"prefix":"","firstName":"Lei","middleName":"","lastName":"Tu","suffix":""},{"id":288313041,"identity":"f5d63658-41fa-45e3-9568-2805555b09fb","order_by":3,"name":"Wei Qian","email":"","orcid":"","institution":"Huazhong University of Science and Technology","correspondingAuthor":false,"prefix":"","firstName":"Wei","middleName":"","lastName":"Qian","suffix":""},{"id":288313042,"identity":"c751a9e8-164e-4328-a223-15067ce41b84","order_by":4,"name":"Fangmei Ling","email":"","orcid":"","institution":"Huazhong University of Science and Technology","correspondingAuthor":false,"prefix":"","firstName":"Fangmei","middleName":"","lastName":"Ling","suffix":""},{"id":288313043,"identity":"6d5a80a8-3716-4932-9446-e46f878f03d0","order_by":5,"name":"Yidong Chen","email":"","orcid":"","institution":"Huazhong University of Science and Technology","correspondingAuthor":false,"prefix":"","firstName":"Yidong","middleName":"","lastName":"Chen","suffix":""},{"id":288313044,"identity":"1e8258c1-3c56-454e-a8f6-5ce0e821a098","order_by":6,"name":"Shuang Li","email":"","orcid":"","institution":"Huazhong University of Science and Technology","correspondingAuthor":false,"prefix":"","firstName":"Shuang","middleName":"","lastName":"Li","suffix":""},{"id":288313045,"identity":"634342ae-dafa-42ec-91e3-5a8d6d08df5e","order_by":7,"name":"Yiyu Cheng","email":"","orcid":"","institution":"Huazhong University of Science and Technology","correspondingAuthor":false,"prefix":"","firstName":"Yiyu","middleName":"","lastName":"Cheng","suffix":""},{"id":288313046,"identity":"98352630-7564-4530-a456-5a28bf06d240","order_by":8,"name":"Huan Wang","email":"","orcid":"","institution":"Huazhong University of Science and Technology","correspondingAuthor":false,"prefix":"","firstName":"Huan","middleName":"","lastName":"Wang","suffix":""},{"id":288313047,"identity":"fbe97c46-d45d-4bab-8762-64f19ab34f3f","order_by":9,"name":"Liangru Zhu","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA8ElEQVRIie3OvQrCMBDA8SuFuERcTwr6CgeCo32VloBTBB/Awaku6iyoD+GijpGCUx/AwUERMjmLQhFbP8bajoL5D8cR8iMBMJl+MQRLec/N3r6PvFwCb8LayaCC5LXxZjFSnw5JHXr71moiLycex1ApSYLbOptYs4iUt9VituusGuWAoDo8kzWKsomNMiEsFIidpVPuE9BOkm0F2YQ9yT0lUjs8JnDzCE+JH4SthDCHs+QVzCGI7a7yx6GHXDer86DBMdLdzegLqU/E4ni9hC6WhMZzXKtVBmJxuH0hn/z+56fpUPkAwC1yyWQymf60B2brTnCbJYIvAAAAAElFTkSuQmCC","orcid":"","institution":"Huazhong University of Science and Technology","correspondingAuthor":true,"prefix":"","firstName":"Liangru","middleName":"","lastName":"Zhu","suffix":""}],"badges":[],"createdAt":"2024-04-05 08:15:45","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-4221555/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-4221555/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":54445676,"identity":"6ee661be-22d8-4ee0-810a-7ac515cdc0bc","added_by":"auto","created_at":"2024-04-10 16:17:06","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":1179775,"visible":true,"origin":"","legend":"\u003cp\u003eDistribution of fecal calprotectin (FC) levels according to partial Mayo score (pMS). The median FC level for pMS \u0026lt;3 was significantly different from pMS 1-12 (\u003cem\u003eP\u003c/em\u003e\u0026lt;0.0001) (\u003cstrong\u003eA\u003c/strong\u003e). Distribution of FC levels according to ulcerative colitis endoscopy index of severity (UCEIS). The median FC level for UCEIS = 0 was significantly different from UCEIS 1-8 (\u003cem\u003eP\u003c/em\u003e \u0026lt;0.0001) (\u003cstrong\u003eB\u003c/strong\u003e). Distribution of FC levels according to Mayo endoscopic score (MES). The median FC level for MES = 0 was significantly different from MES 1-3 (\u003cem\u003eP\u003c/em\u003e \u0026lt;0.0001) (\u003cstrong\u003eC\u003c/strong\u003e). The median FC level for pMS 3-5 was significantly different from pMS 6-10 (\u003cem\u003eP\u003c/em\u003e \u0026lt;0.0001); the median FC level for pMS 6-10 was not significantly different from pMS 11-12 (\u003cem\u003eP\u003c/em\u003e = 0.1754) (\u003cstrong\u003eD\u003c/strong\u003e). The median FC level for UCEIS 1-3 was significantly different from UCEIS 4-6 (\u003cem\u003eP\u003c/em\u003e\u0026lt;0.0001); the median FC level for UCEIS 4-6 was significantly different from UCEIS 7-8 (\u003cem\u003eP\u003c/em\u003e = 0.0062) (\u003cstrong\u003eE\u003c/strong\u003e). The median FC level for MES = 1 was significantly different from MES = 2 (\u003cem\u003eP\u003c/em\u003e \u0026lt;0.0001); the median FC level for MES = 2 was significantly different from MES = 3 (\u003cem\u003eP\u003c/em\u003e = 0.0031) (\u003cstrong\u003eF\u003c/strong\u003e).\u003c/p\u003e","description":"","filename":"Figure1.png","url":"https://assets-eu.researchsquare.com/files/rs-4221555/v1/bd9c4cd40d898289d910a970.png"},{"id":54445673,"identity":"82aa37d2-20b7-4411-b76b-10f0348439a9","added_by":"auto","created_at":"2024-04-10 16:17:04","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":894758,"visible":true,"origin":"","legend":"\u003cp\u003eReceiver operating characteristics (ROC) curve analysis of fecal calprotectin (FC), C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) levels to predict clinical activity (pMS 3-12) in patients with UC (\u003cstrong\u003eA\u003c/strong\u003e). ROC curve analysis of FC, CRP and ESR levels to predict endoscopic activity (UCEIS 1-8) in patients with UC (\u003cstrong\u003eB\u003c/strong\u003e). ROC curve analysis of FC, CRP and ESR levels to predict endoscopic activity (MES 1-3) in patients with UC (\u003cstrong\u003eC\u003c/strong\u003e).\u003c/p\u003e","description":"","filename":"Figure2.png","url":"https://assets-eu.researchsquare.com/files/rs-4221555/v1/8475d059b9267735dfb9d366.png"},{"id":54451160,"identity":"843fdd89-775f-402c-af18-a6345b770a5f","added_by":"auto","created_at":"2024-04-10 18:01:20","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":570948,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-4221555/v1/58dc7681-f1ca-441d-89b7-4ee3b95410ec.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"The value of fecal calprotectin measured by fluorescent immunochromatography assay in evaluating clinical and endoscopic activity in ulcerative colitis","fulltext":[{"header":"Introduction","content":"\u003cp\u003eUlcerative colitis (UC) is a subtype of inflammatory bowel disease (IBD), characterized by mucosal ulceration. Generally, it starts in the rectum and can extend continuously and proximally to the entire colon\u003csup\u003e\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u003c/sup\u003e. The Montreal classification of the extent of UC is divided into three subgroups: E1 (ulcerative proctitis), E2 (left-sided UC) and E3 (extensive UC)\u003csup\u003e\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003eThe clinical course of UC is characterized by alternating periods of remissions and relapses\u003csup\u003e\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u003c/sup\u003e. To avoid disease progression, regular colonoscopy is necessary, as it remains the gold standard for monitoring endoscopic activity\u003csup\u003e\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e\u003c/sup\u003e. However, colonoscopy is an invasive and inconvenient procedure. Therefore, serum biomarkers have been explored as indicators of intestinal inflammation in patients with IBD. C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) are widely used to monitor inflammation flareups\u003csup\u003e\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e\u003c/sup\u003e. However, they are elevated in many inflammatory diseases and poorly correlated with intestinal diseases\u003csup\u003e\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e\u003c/sup\u003e. Fecal biomarkers, on the other hand, can compensate for these deficiencies. They are more specific to intestinal inflammation\u003csup\u003e\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003eCalprotectin is primarily derived from neutrophils\u003csup\u003e\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e\u003c/sup\u003e. Since it can be detected in stools, there is a large amount of evidence suggesting that fecal calprotectin (FC) levels correlate well with the activity of intestinal diseases\u003csup\u003e\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e\u003c/sup\u003e. Currently, it is the most commonly used fecal biomarker for the diagnosis and management of IBD, which helps reduce the frequency of colonoscopy\u003csup\u003e\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan additionalcitationids=\"CR12\" citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e\u003c/sup\u003e. However, there are still some limitations to using FC in predicting disease activity. As detection methods of FC testing have not been standardized and results vary widely between different methods\u003csup\u003e\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e\u003c/sup\u003e, there remains no consensus on the optimal cut-off values to define active UC\u003csup\u003e\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003eFluorescent immunochromatography assay (FICA) is a method that allows for rapid detection of FC, and there are few reports on its use for detecting FC and almost none on the optimal FC cut-off values for this method. To define the optimal FC cut-off values measured by FICA would help us to better manage patients with UC. Therefore, the study aimed to assess the correlation between FC levels and disease activity and identify optimal cut-off values for predicting clinical and endoscopic activity in UC using a detection method based on FICA instead of enzyme-linked immunosorbent assay (ELISA).\u003c/p\u003e"},{"header":"Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003ePatients\u003c/h2\u003e \u003cp\u003eThe patients reviewed were those hospitalized at Union Hospital, Tongji Medical College, Huazhong University of Science and Technology between January 2021 and June 2022. They were diagnosed with UC based on clinical, endoscopic and histologic features. All patients underwent FC testing at the time of colonoscopy.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec4\" class=\"Section2\"\u003e \u003ch2\u003eFC testing\u003c/h2\u003e \u003cp\u003eFC was detected using the calprotectin FICA kit (Wiz Biotech, Xiamen, China) and WIZ-A202 continuous immunoassay analyzer (Wiz Biotech, Xiamen, China). The operation procedure was carried out strictly according to the kit and instrument instructions. Operation procedure: 50 mg of the stool sample was taken into one sample diluent using the sampling stick in the kit, 80 \u0026micro;L of the diluted sample was added into the well of the test card after mixing, and then the test card was put into the continuous immunoassay analyzer, and the result could be read after 15 minutes. The results were in \u0026micro;g/g, with a minimum of 10.00 \u0026micro;g/g. All samples were collected within 1 week prior to the examination and tested within 24 hours of delivery.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec5\" class=\"Section2\"\u003e \u003ch2\u003eMeasures of clinical and endoscopic activity\u003c/h2\u003e \u003cp\u003eThe clinical activity was determined using the partial Mayo score (pMS), whereas endoscopic activity was determined using the ulcerative colitis endoscopy index of severity (UCEIS) and Mayo endoscopic score (MES)\u003csup\u003e\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e, \u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e\u003c/sup\u003e. Clinical remission was defined as pMS\u0026thinsp;\u0026lt;\u0026thinsp;3 and no subscore\u0026thinsp;\u0026gt;\u0026thinsp;1, with mild activity defined as pMS 3\u0026ndash;5, moderate activity as pMS 6\u0026ndash;10 and severe activity as pMS 11\u0026ndash;12. Endoscopic remission was defined as UCEIS\u0026thinsp;=\u0026thinsp;0 or MES\u0026thinsp;=\u0026thinsp;0, mild activity as UCEIS 1\u0026ndash;3 or MES\u0026thinsp;=\u0026thinsp;1, moderate activity as UCEIS 4\u0026ndash;6 or MES\u0026thinsp;=\u0026thinsp;2 and severe activity as UCEIS 7\u0026ndash;8 or MES\u0026thinsp;=\u0026thinsp;3.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec6\" class=\"Section2\"\u003e \u003ch2\u003eStatistical analyses\u003c/h2\u003e \u003cp\u003eCategorical variables were presented as numbers (n) and percentages (%), and continuous variables were presented as mean\u0026thinsp;\u0026plusmn;\u0026thinsp;standard deviation (SD) or median with interquartile range (IQR). The Kolmogorov-Smirnov test was used to evaluate whether continuous variables followed a normal distribution. The Mann-Whitney \u003cem\u003eU\u003c/em\u003e test was used to compare two continuous variables, and Spearman\u0026rsquo;s correlation was used to estimate the association between the parameters. A receiver operating characteristic (ROC) curve analysis with 95% confidence intervals (95% CI) was used to evaluate the performance of FC, CRP and ESR in predicting clinical and endoscopic activity. Youden\u0026rsquo;s \u003cem\u003ej\u003c/em\u003e statistic were calculated for different cut-off values. Statistical analyses were performed using SPSS v 26.0 (IBM, Armonk, New York), and figures were drawn using GraphPad Prism 9 (GraphPad Software, San Diego, California). \u003cem\u003eP-\u003c/em\u003evalues\u0026thinsp;\u0026lt;\u0026thinsp;0.05 were considered statistically significant, and all \u003cem\u003eP-\u003c/em\u003evalues were two-tailed.\u003c/p\u003e \u003c/div\u003e"},{"header":"Results","content":"\u003cdiv id=\"Sec8\" class=\"Section2\"\u003e\n \u003ch2\u003ePatient characteristics\u003c/h2\u003e\n \u003cp\u003eA total of 109 patients with UC were reviewed, including 58.72% males (n\u0026thinsp;=\u0026thinsp;64) and 41.28% females (n\u0026thinsp;=\u0026thinsp;45), with a mean age of 43.96\u0026thinsp;\u0026plusmn;\u0026thinsp;13.87 years, median disease duration of 18 (IQR, 6, 48) months and median body mass index of 22.05 (IQR, 19.30, 24.42) kg/m\u003csup\u003e2\u003c/sup\u003e. FC levels of these patients ranged from 10.00 to 731.01 \u0026micro;g/g, with a median of 78.37 \u0026micro;g/g (IQR, 45.69, 132.34). (See Table \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e for detailed data).\u003c/p\u003e\n \u003cdiv class=\"gridtable\"\u003e\u0026nbsp;\u003ctable id=\"Tab1\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003ePatient Characteristics (n\u0026thinsp;=\u0026thinsp;110)\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eCharacteristics\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eNumber\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eMale, n (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e64 (58.72)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eFemale, n (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e45 (41.28)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eAge at diagnosis, years, mean (SD)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e43.96 (13.87)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eDisease duration, months, median (IQR)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e18 (6, 48)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eBMI, median (IQR)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e22.05 (19.30, 24.42)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eMontreal classification, n (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eE1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e11 (10.09)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eE2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e32 (29.36)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eE3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e66 (60.55)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePrimary symptoms, n (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eHematochezia\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e92 (85.19)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eDiarrhea\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e56 (51.85)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eAbdominal pain\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e41 (37.96)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eSmoking, n (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNever\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e95 (87.16)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eFormer\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e11 (10.09)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eCurrent\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3 (2.75)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eTotal proctocolectomy, n (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0 (0.00)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e109 (100.00)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eMedications, n (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e5-ASA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e87 (79.82)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eCorticosteroids\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e29 (26.61)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eTumor necrosis factor inhibitor\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e16 (14.68)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eVedolizumab\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e11 (10.09)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eImmunomodulators\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3 (2.75)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eLaboratory testing, median (IQR)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eFC (\u0026micro;g/g)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e78.37 (45.69, 132.34)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eCRP (mg/L)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3.34 (3.34, 10.90)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eESR (mm/h)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e10.00 (5.00, 21.50)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eHemoglobin (g/L)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e121.00 (106.00, 135.00)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePlatelets (\u0026times;10\u003csup\u003e9\u003c/sup\u003e/L)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e259.00 (202.00, 326.00)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eWBC (\u0026times;10\u003csup\u003e9\u003c/sup\u003e/L)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e5.97 (4.79, 7.74)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNEUT% (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e60.50 (52.00, 68.03)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eAlbumin (g/L)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e40.10 (36.55, 43.75)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eClinical activity, n (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003epMS\u0026thinsp;\u0026lt;\u0026thinsp;3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e19 (17.43)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003epMS 3\u0026ndash;5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e22 (20.18)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003epMS 6\u0026ndash;10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e53 (48.62)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003epMS 11\u0026ndash;12\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e15 (13.76)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eEndoscopic activity (UCEIS), n (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eUCEIS\u0026thinsp;=\u0026thinsp;0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e8 (7.34)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eUCEIS 1\u0026ndash;3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e32 (29.36)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eUCEIS 4\u0026ndash;6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e53 (48.62)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eUCEIS 7\u0026ndash;8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e16 (14.68)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eEndoscopic activity (MES), n (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eMES\u0026thinsp;=\u0026thinsp;0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e11 (10.09)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eMES\u0026thinsp;=\u0026thinsp;1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e14 (12.84)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eMES\u0026thinsp;=\u0026thinsp;2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e47 (43.12)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eMES\u0026thinsp;=\u0026thinsp;3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e37 (33.94)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003ctfoot\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\"\u003eSD, standard deviation; IQR, interquartile range; 5-ASA, 5-Amino Salicylic Acid; FC, fecal calprotectin; CRP, C-reactive protein; ESR, erythrocyte sedimentation rate; WBC, White blood cell; NEUT%, neutrophil count percentage; pMS, partial Mayo score; UCEIS, ulcerative colitis endoscopy index of severity; MES, Mayo Endoscopic Score\u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tfoot\u003e\n \u003c/table\u003e\n \u003c/div\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec9\" class=\"Section2\"\u003e\n \u003ch2\u003eSignificant differences in FC levels between remission and active disease groups\u003c/h2\u003e\n \u003cp\u003eThe distributions of FC levels according to the pMS, UCEIS and MES were presented in Fig. \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003eA-C, respectively. The FC levels were compared between the remission and active disease groups and between different subgroups of active disease. There were significant differences in FC levels between the remission and active disease groups and between the mildly active and moderately active disease groups based on pMS, UCEIS or MES (Fig. \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003eA-F).\u003c/p\u003e\n \u003cp\u003eThe FC levels in the severely active disease groups were significantly higher than those in the moderately active disease groups. In contrast, there was no difference in the FC levels between the clinically severely active and moderately active disease groups.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec10\" class=\"Section2\"\u003e\n \u003ch2\u003eBetter correlations of FC levels with clinical and endoscopic activity\u003c/h2\u003e\n \u003cp\u003eThe FC levels had high and statistically significant correlations with pMS, UCEIS and MES and were superior to CRP and ESR. The FC levels correlated better with endoscopic activity than with clinical activity. (See Table \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003e for detailed data).\u003c/p\u003e\n \u003cdiv class=\"gridtable\"\u003e\u0026nbsp;\u003ctable id=\"Tab2\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eCorrelations of FC, CRP and ESR levels with disease activity\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\u0026nbsp;\u003c/th\u003e\n \u003cth align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003epMS\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003eUCEIS\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003eMES\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003er\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003er\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003er\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eFC\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.606\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.753\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.642\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eCRP\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.419\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.521\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.380\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eESR\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.284\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.004\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.281\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.004\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.192\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.053\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003ctfoot\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"7\"\u003eFC, fecal calprotectin; CRP, C-reactive protein; ESR, erythrocyte sedimentation rate; pMS, partial Mayo score; UCEIS, ulcerative colitis endoscopy index of severity; MES, Mayo endoscopic score\u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tfoot\u003e\n \u003c/table\u003e\n \u003c/div\u003e\n \u003cp\u003eMoreover, the correlations between FC levels and disease activity may be influenced by the extent of the disease. The FC levels for E1 correlated the best with disease activity, followed by E2 and E3. (See Table \u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003e for detailed data).\u003c/p\u003e\n \u003cdiv class=\"gridtable\"\u003e\u0026nbsp;\u003ctable id=\"Tab3\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eCorrelations of FC levels with disease activity in different disease extents\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\u0026nbsp;\u003c/th\u003e\n \u003cth align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003epMS\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003eUCEIS\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003eMES\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003er\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003er\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003er\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eE1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.716\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.013\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.833\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.678\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.022\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eE2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.664\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.719\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.621\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eE3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.485\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.657\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.564\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003ctfoot\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"7\"\u003eFC, fecal calprotectin; E1, ulcerative proctitis; E2, left-sided ulcerative colitis; E3, extensive ulcerative colitis; pMS, partial Mayo score; UCEIS, ulcerative colitis endoscopy index of severity; MES, Mayo endoscopic score\u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tfoot\u003e\n \u003c/table\u003e\n \u003c/div\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec11\" class=\"Section2\"\u003e\n \u003ch2\u003eFC levels of patients with clinical remission but no endoscopic remission\u003c/h2\u003e\n \u003cp\u003eIn clinical practice, there is a discrepancy between clinical activity and endoscopic activity in some patients with UC. In our study, 11 patients had clinical remission but no endoscopic remission. These patients had FC levels ranging from 10.00 to 55.65 \u0026micro;g/g with a median of 22.28 (IQR, 10.97, 39.27) \u0026micro;g/g, pMS ranging from 0 to 2, UCEIS ranging from 1 to 4 and MES ranging from 0 to 1. (See Table \u003cspan class=\"InternalRef\"\u003e4\u003c/span\u003e for detailed data).\u003c/p\u003e\n \u003cdiv class=\"gridtable\"\u003e\u0026nbsp;\u003ctable id=\"Tab4\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 4\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eFC levels of patients with clinical remission but no endoscopic remission\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\u0026nbsp;\u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eFC levels (\u0026micro;g/g)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003epMS\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eUCEIS\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eMES\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePatient 1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e10.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cbr\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePatient 2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e10.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cbr\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePatient 3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e10.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePatient 4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e11.94\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePatient 5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e14.19\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePatient 6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e22.28\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cbr\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePatient 7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e28.37\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePatient 8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e33.34\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePatient 9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e45.19\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePatient 10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e51.87\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePatient 11\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e55.65\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colspan=\"5\"\u003e\n \u003cp\u003eFC, fecal calprotectin; pMS, partial Mayo score; UCEIS, ulcerative colitis endoscopy index of severity; MES, Mayo endoscopic score\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n \u003c/div\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec12\" class=\"Section2\"\u003e\n \u003ch2\u003eOptimal FC cut-off values\u003c/h2\u003e\n \u003cp\u003eThe area under the curve (AUC) in the ROC curve analysis of FC levels to predict pMS 3\u0026ndash;12 was 0.9450 (95% CI, 0.8998 to 0.9903; \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.0001), which was superior to CRP 0.6954 (95% CI, 0.5829 to 0.8079; \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.0078) and ESR 0.6225 (95% CI, 0.4724 to 0.7725; \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.1210) (Fig. \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003eA).\u003c/p\u003e\n \u003cp\u003eTo predict UCEIS 1\u0026ndash;8, the AUC in the ROC curve analysis of FC levels was 0.9066 (95% CI, 0.8244 to 0.9887; \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.0001), followed by CRP 0.7245 (95% CI, 0.5953 to 0.8537; \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.0353) and ESR 0.7598 (95% CI, 0.5949 to 0.9247; \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.0508) (Fig. \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003eB).\u003c/p\u003e\n \u003cp\u003eTo predict MES 1\u0026ndash;3, the AUC in the ROC curve analysis of FC levels was 0.9109 (95% CI, 0.8392 to 0.9827; \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.0001), followed by CRP 0.7316 (95% CI, 0.6178 to 0.8454; \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.0122) and ESR 0.6922 (95% CI, 0.5241 to 0.8603; \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.0721) (Fig. \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003eC). The optimal FC cut-off values to identify active UC were presented in Table \u003cspan class=\"InternalRef\"\u003e5\u003c/span\u003e.\u003c/p\u003e\n \u003cdiv class=\"gridtable\"\u003e\u0026nbsp;\u003ctable id=\"Tab5\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 5\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eOptimal FC cut-off values\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\u0026nbsp;\u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003epMS 3\u0026ndash;12\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eUCEIS 1\u0026ndash;8\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eMES 1\u0026ndash;3\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eCut-off value (\u0026micro;g/g)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u0026ge;\u0026thinsp;57.38\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u0026ge;\u0026thinsp;53.30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u0026ge;\u0026thinsp;53.30\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eSensitivity (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e77.78\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e71.29\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e73.47\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eSpecificity (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e100\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e100\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e100\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003ctfoot\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"4\"\u003eFC, fecal calprotectin; pMS, partial Mayo score; UCEIS, ulcerative colitis endoscopy index of severity; MES, Mayo endoscopic score\u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tfoot\u003e\n \u003c/table\u003e\n \u003c/div\u003e\n\u003c/div\u003e"},{"header":"Discussion","content":"\u003cp\u003eFC, an effective non-invasive biomarker of inflammation in the colon, has been used as a companion tool for diagnosing, monitoring and treating UC for several years\u003csup\u003e\u003cspan class=\"CitationRef\"\u003e10\u003c/span\u003e, \u003cspan class=\"CitationRef\"\u003e18\u003c/span\u003e\u003c/sup\u003e. However, the optimal cut-off values of FC for predicting disease activity in UC are still debated.\u003c/p\u003e\n\u003cp\u003eStudies have suggested using values\u0026thinsp;\u0026ge;\u0026thinsp;121 \u0026micro;g/g or even higher to predict endoscopic activity\u003csup\u003e\u003cspan class=\"CitationRef\"\u003e19\u003c/span\u003e, \u003cspan class=\"CitationRef\"\u003e20\u003c/span\u003e\u003c/sup\u003e, which did not work in our cases. In our study, 54.13% (n\u0026thinsp;=\u0026thinsp;59) of patients with UCEIS scores of 1\u0026ndash;8 had FC levels below 100 \u0026micro;g/g. Therefore, we analyzed the correlation between FC levels and disease activity and redefined the optimal cut-off values. Consistent with previous findings\u003csup\u003e\u003cspan class=\"CitationRef\"\u003e10\u003c/span\u003e, \u003cspan class=\"CitationRef\"\u003e18\u003c/span\u003e\u003c/sup\u003e, our study demonstrated that FC levels correlated well with clinical and endoscopic activity in UC and were superior to CRP and ESR. We found that, compared to clinical activity, FC levels had a higher correlation with endoscopic activity, especially with UCEIS. This may be due to the ability of the UCEIS to distinguish endoscopic activity in greater detail\u003csup\u003e\u003cspan class=\"CitationRef\"\u003e21\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e\n\u003cp\u003eThe optimal FC cut-off value to identify clinical activity (pMS 3\u0026ndash;12) was determined as 57.38 \u0026micro;g/g in patients with UC. To identify endoscopic activity (UCEIS 1\u0026ndash;8 or MES 1\u0026ndash;3), a lower value should be chosen, which was determined as 53.30 \u0026micro;g/g. These values were significantly lower than those previously reported, probably because we used FICA rather than ELISA to detect FC\u003csup\u003e\u003cspan class=\"CitationRef\"\u003e14\u003c/span\u003e\u003c/sup\u003e. As the most widely used method currently, ELISA is the standard quantitative test for detecting FC, however, it is expensive and time-consuming\u003csup\u003e\u003cspan class=\"CitationRef\"\u003e22\u003c/span\u003e\u003c/sup\u003e. FICA, a valid alternative to ELISA\u003csup\u003e\u003cspan class=\"CitationRef\"\u003e15\u003c/span\u003e\u003c/sup\u003e, is easier and faster to perform, and its results have been reported to correlate highly with ELISA results\u003csup\u003e\u003cspan class=\"CitationRef\"\u003e23\u003c/span\u003e\u003c/sup\u003e. Through ROC curve analysis, we confirmed that FICA-based FC testing was better at predicting clinical and endoscopic activity in UC than CRP and ESR.\u003c/p\u003e\n\u003cp\u003eAccording to STRIDE-II, endoscopic healing (UCEIS\u0026thinsp;\u0026le;\u0026thinsp;1 or MES\u0026thinsp;=\u0026thinsp;0) is the long-term target for UC\u003csup\u003e\u003cspan class=\"CitationRef\"\u003e20\u003c/span\u003e\u003c/sup\u003e. In our study, some patients with UC had a discrepancy between clinical activity and endoscopic activity. These patients were with clinical remission but had mild endoscopic activity. Their FC levels ranged from 10.00 to 55.65 \u0026micro;g/g, with 10 patients (90.91%) having FC levels below 53.30 \u0026micro;g/g. This suggested that in some patients with UC, even though their FC levels were within the normal range, they may not have achieved endoscopic healing. Our study showed that this group of patients usually did not have severe endoscopic activity, and their endoscopic findings were mainly erythema and/or decreased vascular pattern. However, it still suggested that although FC is an effective biomarker of clinical and endoscopic activity in UC, colonoscopy remains the gold standard for determining endoscopic activity, and FC could play an adjunctive role to reduce the frequency of colonoscopy.\u003c/p\u003e\n\u003cp\u003eMoreover, the extent of UC probably impacted the reliability of FC in predicting disease activity. We analyzed the correlation between FC levels and disease activity in patients with UC with different disease extents. It was observed that FC levels for patients with E1 had the highest correlation with disease activity, followed by E2 and E3. The small sample size may have influenced our findings. Specifically, the sample size of the patients with E1 was relatively small. However, our observation has been suggested that different subgroups of UC may require different cut-off values. Further confirmation would require studies with larger sample sizes.\u003c/p\u003e\n\u003cp\u003eThe pre-analytical phase of FC is also very important, especially stool sampling procedure, which could influence FC measurement\u003csup\u003e\u003cspan class=\"CitationRef\"\u003e22\u003c/span\u003e, \u003cspan class=\"CitationRef\"\u003e24\u003c/span\u003e\u003c/sup\u003e. In our study, some patients with pMS 11\u0026ndash;12 had FC levels below 100 \u0026micro;g/g, probably due to severe diarrhea, making the sampling procedure substandard. As a fecal biomarker, FC has the advantages of being non-invasive and more specific for intestinal inflammation than serum biomarkers, such as CRP and ESR. However, the lack of standardization of the sampling procedure is a limitation. Preference should be given to patients with normally formed stools from the first bowel movement in the morning\u003csup\u003e\u003cspan class=\"CitationRef\"\u003e24\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e\n\u003cp\u003eIn summary, our results showed that FC was a good predictor of clinical and endoscopic activity in patients with UC. However, stool sampling needed to be standardized. When using FICA to detect FC, 57.38 \u0026micro;g/g and 53.30 \u0026micro;g/g should be chosen to identify patients with UC with clinical and endoscopic activity, respectively.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthics statement\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis study was reviewed and approved by the Ethics Committee of Union Hospital, Tongji Medical College, Huazhong University of Science and Technology (Approval Number: 20220827). It was confirmed that informed consent was obtained from all subjects and/or their legal guardian(s) and that all methods were performed in accordance with the relevant guidelines and regulations.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eMingyang Xu and Junrong Li contributed equally to this study. Mingyang Xu collected and analyzed the data and drafted and revised the manuscript. Junrong Li helped with data collection and analysis. Wei Qian provided the test results for the FC. Lei Tu, Fangmei Ling, Yidong Chen, Shuang Li and Yiyu Cheng participated in the revision of the manuscript. Huan Wang and Liangru Zhu designed the study, checked the data and analysis results and made the final revisions to the manuscript. All the authors approved the final version of the manuscript.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis study was supported by the National Natural Science Foundation of China (82170547 and 81873558).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConflict of interest\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThere was no conflict of interest to declare.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData availability\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe datasets used and/or analysed during the current study available from the corresponding author on reasonable request.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n \u003cli\u003eUngaro R, Mehandru S, Allen PB, et al. Ulcerative colitis. Lancet. 2017 Apr 29;389(10080):1756-1770. doi: 10.1016/S0140-6736(16)32126-2\u003c/li\u003e\n \u003cli\u003eSatsangi J, Silverberg MS, Vermeire S, et al. The Montreal classification of inflammatory bowel disease: controversies, consensus, and implications. Gut. 2006 Jun;55(6):749-53. doi: 10.1136/gut.2005.082909\u003c/li\u003e\n \u003cli\u003eLamb CA, Kennedy NA, Raine T, et al. British Society of Gastroenterology consensus guidelines on the management of inflammatory bowel disease in adults. Gut. 2019 Dec;68(Suppl 3):s1-s106. doi: 10.1136/gutjnl-2019-318484\u003c/li\u003e\n \u003cli\u003eSands BE. Biomarkers of Inflammation in Inflammatory Bowel Disease. Gastroenterology. 2015 Oct;149(5):1275-1285.e2. doi: 10.1053/j.gastro.2015.07.003\u003c/li\u003e\n \u003cli\u003eLiu D, Saikam V, Skrada KA, et al. Inflammatory bowel disease biomarkers. Med Res Rev. 2022 Sep;42(5):1856-1887. doi: 10.1002/med.21893\u003c/li\u003e\n \u003cli\u003eLewis JD. The utility of biomarkers in the diagnosis and therapy of inflammatory bowel disease. Gastroenterology. 2011 May;140(6):1817-1826.e2. doi: 10.1053/j.gastro.2010.11.058\u003c/li\u003e\n \u003cli\u003eKopylov U, Rosenfeld G, Bressler B, et al. Clinical utility of fecal biomarkers for the diagnosis and management of inflammatory bowel disease. Inflamm Bowel Dis. 2014 Apr;20(4):742-56. doi: 10.1097/01.MIB.0000442681.85545.31\u003c/li\u003e\n \u003cli\u003eAyling RM, Kok K. Fecal Calprotectin. Adv Clin Chem. 2018;87:161-190. doi: 10.1016/bs.acc.2018.07.005\u003c/li\u003e\n \u003cli\u003eMagro F, Gionchetti P, Eliakim R, et al. Third European Evidence-based Consensus on Diagnosis and Management of Ulcerative Colitis. Part 1: Definitions, Diagnosis, Extra-intestinal Manifestations, Pregnancy, Cancer Surveillance, Surgery, and Ileo-anal Pouch Disorders. J Crohns Colitis. 2017 Jun 1;11(6):649-670. doi: 10.1093/ecco-jcc/jjx008\u003c/li\u003e\n \u003cli\u003eJukic A, Bakiri L, Wagner EF, et al. Calprotectin: from biomarker to biological function. Gut. 2021 Oct;70(10):1978-1988. doi: 10.1136/gutjnl-2021-324855\u003c/li\u003e\n \u003cli\u003eKonikoff MR, Denson LA. Role of fecal calprotectin as a biomarker of intestinal inflammation in inflammatory bowel disease. Inflamm Bowel Dis. 2006 Jun;12(6):524-34. doi: 10.1097/00054725-200606000-00013\u003c/li\u003e\n \u003cli\u003eRicciuto A, Griffiths AM. Clinical value of fecal calprotectin. Crit Rev Clin Lab Sci. 2019 Aug;56(5):307-320. doi: 10.1080/10408363.2019.1619159\u003c/li\u003e\n \u003cli\u003eD\u0026rsquo;Haens G, Ferrante M, Vermeire S, et al. Fecal calprotectin is a surrogate marker for endoscopic lesions in inflammatory bowel disease. Inflamm Bowel Dis. 2012 Dec;18(12):2218-24. doi: 10.1002/ibd.22917\u003c/li\u003e\n \u003cli\u003eLabaere D, Smismans A, Van Olmen A, et al. Comparison of six different calprotectin assays for the assessment of inflammatory bowel disease. United European Gastroenterol J. 2014 Feb;2(1):30-7. doi: 10.1177/2050640613518201\u003c/li\u003e\n \u003cli\u003eD\u0026rsquo;Amico F, Rubin DT, Kotze PG, et al. International consensus on methodological issues in standardization of fecal calprotectin measurement in inflammatory bowel diseases. United European Gastroenterol J. 2021 May;9(4):451-460. doi: 10.1002/ueg2.12069\u003c/li\u003e\n \u003cli\u003eD\u0026rsquo;Haens G, Sandborn WJ, Feagan BG, et al. A review of activity indices and efficacy end points for clinical trials of medical therapy in adults with ulcerative colitis. Gastroenterology. 2007 Feb;132(2):763-86. Doi: 10.1053/j.gastro.2006.12.038\u003c/li\u003e\n \u003cli\u003eTravis SP, Schnell D, Feagan BG, et al. The Impact of Clinical Information on the Assessment of Endoscopic Activity: Characteristics of the Ulcerative Colitis Endoscopic Index Of Severity [UCEIS]. J Crohns Colitis. 2015 Aug;9(8):607-16. doi: 10.1093/ecco-jcc/jjv077\u003c/li\u003e\n \u003cli\u003eLouis E. Fecal calprotectin: towards a standardized use for inflammatory bowel disease management in routine practice. J Crohns Colitis. 2015 Jan;9(1):1-3. doi: 10.1093/ecco-jcc/jju012\u003c/li\u003e\n \u003cli\u003eHart L, Chavannes M, Kherad O, et al. Faecal Calprotectin Predicts Endoscopic and Histological Activity in Clinically Quiescent Ulcerative Colitis. J Crohns Colitis. 2020 Jan 1;14(1):46-52. doi: 10.1093/ecco-jcc/jjz107\u003c/li\u003e\n \u003cli\u003eTurner D, Ricciuto A, Lewis A, et al. STRIDE-II: An Update on the Selecting Therapeutic Targets in Inflammatory Bowel Disease (STRIDE) Initiative of the International Organization for the Study of IBD (IOIBD): Determining Therapeutic Goals for Treat-to-Target strategies in IBD. Gastroenterology. 2021 Apr;160(5):1570-1583. doi: 10.1053/j.gastro.2020.12.031\u003c/li\u003e\n \u003cli\u003eArai M, Naganuma M, Sugimoto S, et al. The Ulcerative Colitis Endoscopic Index of Severity is Useful to Predict Medium- to Long-Term Prognosis in Ulcerative Colitis Patients with Clinical Remission. J Crohns Colitis. 2016 Nov;10(11):1303-1309. doi: 10.1093/ecco-jcc/jjw104\u003c/li\u003e\n \u003cli\u003eD\u0026rsquo;Amico F, Nancey S, Danese S, et al. A Practical Guide for Faecal Calprotectin Measurement: Myths and Realities. J Crohns Colitis. 2021 Jan 13;15(1):152-161. doi: 10.1093/ecco-jcc/jjaa093\u003c/li\u003e\n \u003cli\u003eLi R, Zhao X, Dong J, et al. Evaluation of a fluorescent immunochromatography test for fecal calprotectin. J Clin Lab Anal. 2020 Feb;34(2):e23059. doi: 10.1002/jcla.23059\u003c/li\u003e\n \u003cli\u003eLasson A, Stotzer PO, \u0026Ouml;hman L, et al. The intra-individual variability of faecal calprotectin: a prospective study in patients with active ulcerative colitis. J Crohns Colitis. 2015 Jan;9(1):26-32. doi: 10.1016/j.crohns.2014.06.002\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"fecal calprotectin, ulcerative colitis, clinical activity, endoscopic activity, cut-off value","lastPublishedDoi":"10.21203/rs.3.rs-4221555/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-4221555/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eAim: \u003c/strong\u003eFecal calprotectin (FC) levels correlate with clinical or endoscopic activity in ulcerative colitis (UC), however, these values vary widely between detection methods, and optimal cut-off values remain debated.\u003cstrong\u003e \u003c/strong\u003eTo assess the correlation between FC levels measured by fluorescent immunochromatography assay (FICA) and disease activity and to identify optimal cut-off values for predicting clinical and endoscopic activity in UC.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethod: \u003c/strong\u003ePatients reviewed were hospitalized at Union Hospital, Tongji Medical College, Huazhong University of Science and Technology between January 2021 and June 2022. All the patients had a confirmed diagnosis of UC. Clinical activity was determined using the partial Mayo score (pMS), and endoscopic activity was determined using the ulcerative colitis endoscopy index of severity (UCEIS) and Mayo endoscopic score (MES).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults: \u003c/strong\u003eIn\u003cstrong\u003e \u003c/strong\u003e109 patients with UC, FC levels were significantly correlated with pMS (r = 0.606, \u003cem\u003eP\u003c/em\u003e \u0026lt;0.001), UCEIS (r = 0.753, \u003cem\u003eP\u003c/em\u003e \u0026lt;0.001) and MES (r = 0.642, \u003cem\u003eP\u003c/em\u003e\u0026lt;0.001). Moreover, the optimal FC cut-off values to predict clinical activity (pMS 3-12) and endoscopic activity (UCEIS 1-8 or MES 1-3) were 57.38 μg/g and 53.30 μg/g, respectively.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusion: \u003c/strong\u003eFC measured by FICA was a good predictor of clinical and endoscopic activity in patients with UC. When using FICA to detect FC, the optimal cut-off value to identify clinical activity in patients with UC was 57.38 μg/g, and a lower value should be chosen to optimize the identification of endoscopic activity in these patients, which was determined as 53.30 μg/g.\u003c/p\u003e","manuscriptTitle":"The value of fecal calprotectin measured by fluorescent immunochromatography assay in evaluating clinical and endoscopic activity in ulcerative colitis","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-04-10 16:16:37","doi":"10.21203/rs.3.rs-4221555/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"1bd82f37-ca05-49c4-8e45-6dc724e30e14","owner":[],"postedDate":"April 10th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2024-04-10T18:01:09+00:00","versionOfRecord":[],"versionCreatedAt":"2024-04-10 16:16:37","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-4221555","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-4221555","identity":"rs-4221555","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}