scholarly journals Development and validation of a novel counter-immunoelectrophoresis assay for the detection of antibodies against extractable nuclear antigens

2021 ◽  
Author(s):  
◽  
Reuben Wallis
Keyword(s):  
Connective Tissue ◽  
Likelihood Ratio ◽  
Connective Tissue Diseases ◽  
Positive Likelihood Ratio ◽  
Negative Likelihood Ratio ◽  
Rater Agreement ◽  
Diagnostic Specificity ◽  
Nuclear Antigens ◽  
Sera Samples ◽  
Assay Conditions

<p>The identification of autoantibodies is a primary diagnostic marker for the diagnosis of some autoimmune diseases. The sera of patients with connective tissue diseases commonly contain autoantibodies that target nuclear antigens. As such these antibodies are called antinuclear antibodies (ANAs). Furthermore, the clinical identification of ANAs in patient sera to specific nuclear antigens is a primary tool for the diagnosis of connective tissue diseases. For this purpose specific extractable nuclear antigens (ENAs) are used. The most commonly employed laboratory technique for the detection of ENA antibodies is the enzyme linked immunoabsorbant assay (ELISA). ELISA is a simple technique that can be automated and provides high diagnostic sensitivity for the detection of ENA antibodies comparatively to a counter immunoelectrophoresis (CIE) assay. However, compared to CIE ELISA lacks diagnostic specificity. Therefore there is a demand for an assay with high diagnostic specificity as a secondary diagnostic test for the detection of ENA antibodies. The central aim of this project was to develop and validate a novel CIE assay that used fluorescently labelled ENAs to detect ENA antibodies in patient serum.   Development of the assay began with comparative testing of fluorescently labelled and unlabelled antigens to confirm that the immunochemical properties of the antigen remained intact. The CIE assay conditions were optimised for the detection of four ANAs SSA, SSB, RNP/Sm, and Sm using their corresponding ENAs. Assay conditions optimised were flurophore type, gel composition, buffer composition, antigen concentration, the running time, and analytical specificity. Evaluation of 281 clinical sera samples known to have previously tested positive test by ANA indirect immunofluorescence were performed using the optimised CIE assay and ELISA. The inter-rater agreement between the CIE assay and ELISA results was determined. Clinical details were used to retrospectively classify the clinical sera samples into clinical categories and case groups. This data was used for the diagnostic comparison of the CIE assay and ELISA results.  There was strong inter-rater agreement between the SSA CIE assay and ELISA results. The diagnostic specificity and positive likelihood ratio values of the SSA CIE assay were superior to those of the ELISA, while diagnostic sensitivity and the negative likelihood ratio values were approximately the same. There was strong inter-rater agreement between the RNP/Sm CIE assay and ELISA. However, it was observed that the statistical measures of assay accuracy (diagnostic specificity and sensitivity, positive likelihood ratio, and negative likelihood ratio) for the RNP/Sm ELISA were superior to those of CIE assay. The diagnostic specificity of the SSB and Sm CIE assays were higher than that of their respective ELISAs. This was also true for the positive likelihood ratio values of the SSB and Sm CIE assays when compared to their respect ELISAs.  The SSA CIE assay results suggest that this assay maybe a suitable replacement for ELISA as a diagnostic tool for the identification of anti-SSA antibodies and Sjogren’s syndrome. The SSB and Sm CIE assay results suggest that these assays would be suitable as secondary confirmatory diagnostic assays for the identification of their respective ENA antibodies. However, further performance evaluation of the assays within a routine diagnostic laboratory is required.</p>

scholarly journals Development and validation of a novel counter-immunoelectrophoresis assay for the detection of antibodies against extractable nuclear antigens

2021 ◽  
Author(s):  
◽  
Reuben Wallis
Keyword(s):  
Connective Tissue ◽  
Likelihood Ratio ◽  
Connective Tissue Diseases ◽  
Positive Likelihood Ratio ◽  
Negative Likelihood Ratio ◽  
Rater Agreement ◽  
Diagnostic Specificity ◽  
Nuclear Antigens ◽  
Sera Samples ◽  
Assay Conditions

<p>The identification of autoantibodies is a primary diagnostic marker for the diagnosis of some autoimmune diseases. The sera of patients with connective tissue diseases commonly contain autoantibodies that target nuclear antigens. As such these antibodies are called antinuclear antibodies (ANAs). Furthermore, the clinical identification of ANAs in patient sera to specific nuclear antigens is a primary tool for the diagnosis of connective tissue diseases. For this purpose specific extractable nuclear antigens (ENAs) are used. The most commonly employed laboratory technique for the detection of ENA antibodies is the enzyme linked immunoabsorbant assay (ELISA). ELISA is a simple technique that can be automated and provides high diagnostic sensitivity for the detection of ENA antibodies comparatively to a counter immunoelectrophoresis (CIE) assay. However, compared to CIE ELISA lacks diagnostic specificity. Therefore there is a demand for an assay with high diagnostic specificity as a secondary diagnostic test for the detection of ENA antibodies. The central aim of this project was to develop and validate a novel CIE assay that used fluorescently labelled ENAs to detect ENA antibodies in patient serum.   Development of the assay began with comparative testing of fluorescently labelled and unlabelled antigens to confirm that the immunochemical properties of the antigen remained intact. The CIE assay conditions were optimised for the detection of four ANAs SSA, SSB, RNP/Sm, and Sm using their corresponding ENAs. Assay conditions optimised were flurophore type, gel composition, buffer composition, antigen concentration, the running time, and analytical specificity. Evaluation of 281 clinical sera samples known to have previously tested positive test by ANA indirect immunofluorescence were performed using the optimised CIE assay and ELISA. The inter-rater agreement between the CIE assay and ELISA results was determined. Clinical details were used to retrospectively classify the clinical sera samples into clinical categories and case groups. This data was used for the diagnostic comparison of the CIE assay and ELISA results.  There was strong inter-rater agreement between the SSA CIE assay and ELISA results. The diagnostic specificity and positive likelihood ratio values of the SSA CIE assay were superior to those of the ELISA, while diagnostic sensitivity and the negative likelihood ratio values were approximately the same. There was strong inter-rater agreement between the RNP/Sm CIE assay and ELISA. However, it was observed that the statistical measures of assay accuracy (diagnostic specificity and sensitivity, positive likelihood ratio, and negative likelihood ratio) for the RNP/Sm ELISA were superior to those of CIE assay. The diagnostic specificity of the SSB and Sm CIE assays were higher than that of their respective ELISAs. This was also true for the positive likelihood ratio values of the SSB and Sm CIE assays when compared to their respect ELISAs.  The SSA CIE assay results suggest that this assay maybe a suitable replacement for ELISA as a diagnostic tool for the identification of anti-SSA antibodies and Sjogren’s syndrome. The SSB and Sm CIE assay results suggest that these assays would be suitable as secondary confirmatory diagnostic assays for the identification of their respective ENA antibodies. However, further performance evaluation of the assays within a routine diagnostic laboratory is required.</p>

scholarly journals The Potential Diagnostic Accuracy of Circulating MicroRNAs for Leukemia: A Meta-Analysis

2021 ◽  
Vol 20 ◽  
pp. 153303382110119
Author(s):  
Wen-Ting Zhang ◽  
Guo-Xun Zhang ◽  
Shuai-Shuai Gao
Keyword(s):  
Diagnostic Accuracy ◽  
Likelihood Ratio ◽  
Subgroup Analysis ◽  
Meta Analysis ◽  
Area Under The Curve ◽  
Positive Likelihood Ratio ◽  
Negative Likelihood Ratio ◽  
Diagnostic Odds Ratio ◽  
Circulating Micrornas ◽  
Sensitivity Specificity

Background: Leukemia is a common malignant disease in the human blood system. Many researchers have proposed circulating microRNAs as biomarkers for the diagnosis of leukemia. We conducted a meta-analysis to evaluate the diagnostic accuracy of circulating miRNAs in the diagnosis of leukemia. Methods: A comprehensive literature search (updated to October 13, 2020) in PubMed, EMBASE, Web of Science, Cochrane Library, Wanfang database and China National Knowledge Infrastructure (CNKI) was performed to identify eligible studies. The sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR), and area under the curve (AUC) for diagnosing leukemia were pooled for both overall and subgroup analysis. The meta-regression and subgroup analysis were performed to explore heterogeneity and Deeks’ funnel plot was used to assess publication bias. Results: 49 studies from 22 publications with a total of 3,489 leukemia patients and 2,756 healthy controls were included in this meta-analysis. The overall sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio and area under the curve were 0.83, 0.92, 10.8, 0.18, 59 and 0.94, respectively. Subgroup analysis shows that the microRNA clusters of plasma type could carry out a better diagnostic accuracy of leukemia patients. In addition, publication bias was not found. Conclusions: Circulating microRNAs can be used as a promising noninvasive biomarker in the early diagnosis of leukemia.

scholarly journals The value of glycosylated hemoglobin in the diagnosis of diabetic retinopathy: a systematic review and Meta-analysis

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Bo Zhang ◽  
Bingjie Zhang ◽  
Zhulin Zhou ◽  
Yutong Guo ◽  
Dan Wang
Keyword(s):  
Diabetic Retinopathy ◽  
Likelihood Ratio ◽  
Roc Curve ◽  
Meta Analysis ◽  
Glycosylated Hemoglobin ◽  
Positive Likelihood Ratio ◽  
Negative Likelihood Ratio ◽  
Biomedical Literature ◽  
Cochrane Library ◽  
Clinical Value

AbstractObjectiveGlycosylated hemoglobin (HbA1c) has obvious clinical value in the diagnosis of diabetes, but the conclusions on the diagnostic value of diabetic retinopathy (DR) are not consistent. This study aims to comprehensively evaluate the accuracy of glycosylated hemoglobin in the diagnosis of diabetic retinopathy through the meta-analysis of diagnostic tests.MethodsCochrane Library, Embase, PubMed, Web of Science, China National Knowledge Infrastructure (CNKI), China Wanfang Database, Chinese Biomedical Literature Database (CBM) were searched until November, 2020. The Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) tool was used to assess the quality of the included studies. The pooled sensitivity, specificity, positive likelihood ratio (+LR), negative likelihood ratio (-LR), diagnostic odds ratio (DOR) and areas under the receiver operating characteristic (ROC) curve were calculated by Stata 15.0 software.ResultsAfter screening, 18 high-quality papers were included. The results of meta-analysis showed that the combined DOR = 18.19 (95% CI: 10.99–30.11), the sensitivity= 0.81 (95% CI): 0.75 ~ 0.87), specificity = 0.81 (95%CI: 0.72 ~ 0.87), +LR = 4.2 (95%CI: 2.95 ~ 6.00), −LR = 0.23 (95%CI: 0.17 ~ 0.31), and the area under the Summary ROC curve was 0.88 (95%CI:  0.85 ~ 0.90).ConclusionThe overall accuracy of HbA1cC forin diagnosing diabetic retinopathy is good. As it is more stable than blood sugar and is not affected by meals, it may be a suitable indicator for diabetic retinopathy.

scholarly journals Circulating tumour DNA methylation in hepatocellular carcinoma diagnosis using digital droplet PCR

2021 ◽  
Vol 49 (3) ◽  
pp. 030006052199296
Author(s):  
Juan Wang ◽  
Liu Yang ◽  
Yanjun Diao ◽  
Jiayun Liu ◽  
Jinjie Li ◽  
...  
Keyword(s):  
Hepatocellular Carcinoma ◽  
Dna Methylation ◽  
Likelihood Ratio ◽  
Predictive Value ◽  
Positive Likelihood Ratio ◽  
Negative Likelihood Ratio ◽  
Control Group ◽  
Control Subjects ◽  
Droplet Pcr ◽  
Healthy Control

Objective To evaluate the performance of a DNA methylation-based digital droplet polymerase chain reaction (ddPCR) assay to detect aberrant DNA methylation in cell-free DNA (cfDNA) and to determine its application in the detection of hepatocellular carcinoma (HCC). Methods The present study recruited patients with liver-related diseases and healthy control subjects. Blood samples were used for the extraction of cfDNA, which was then bisulfite converted and the extent of DNA methylation quantified using a ddPCR platform. Results A total of 97 patients with HCC, 80 healthy control subjects and 46 patients with chronic hepatitis B/C virus infection were enrolled in the study. The level of cfDNA in the HCC group was significantly higher than that in the healthy control group. For the detection of HCC, based on a cut-off value of 15.7% for the cfDNA methylation ratio, the sensitivity and specificity were 78.57% and 89.38%, respectively. The diagnostic accuracy was 85.27%, the positive predictive value was 81.91% and the negative predictive value was 87.20%. The positive likelihood ratio of 15.7% in HCC diagnosis was 7.40, while the negative likelihood ratio was 0.24. Conclusions A sensitive methylation-based assay might serve as a liquid biopsy test for diagnosing HCC.

scholarly journals Test characteristics of history, examination and investigations in the evaluation for septic arthritis in the child presenting with acute non-traumatic limp. A systematic review

BMJ Open ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. e038088
Author(s):  
Jacky Tu ◽  
Peter Gowdie ◽  
Julian Cassar ◽  
Simon Craig
Keyword(s):  
Systematic Review ◽  
Diagnostic Accuracy ◽  
Septic Arthritis ◽  
Quality Assessment ◽  
Likelihood Ratio ◽  
Risk Prediction ◽  
Positive Likelihood Ratio ◽  
Negative Likelihood Ratio ◽  
Prediction Tools ◽  
Clinical Risk

BackgroundSeptic arthritis is an uncommon but potentially significant diagnosis to be considered when a child presents to the emergency department (ED) with non-traumatic limp. Our objective was to determine the diagnostic accuracy of clinical findings (history and examination) and investigation results (pathology tests and imaging) for the diagnosis of septic arthritis among children presenting with acute non-traumatic limp to the ED.MethodsSystematic review of the literature published between 1966 and June 2019 on MEDLINE and EMBASE databases. Studies were included if they evaluated children presenting with lower limb complaints and evaluated diagnostic performance of items from history, physical examination, laboratory testing or radiological examination. Data were independently extracted by two authors, and quality assessment was performed using the Quality Assessment Tool for Diagnostic Accuracy Studies 2 tool.Results18 studies were identified, and included 2672 children (560 with a final diagnosis of septic arthritis). There was substantial heterogeneity in inclusion criteria, study setting, definitions of specific variables and the gold standard used to confirm septic arthritis. Clinical and investigation findings were reported using varying definitions and cut-offs, and applied to differing study populations. Spectrum bias and poor-to-moderate study design quality limit their applicability to the ED setting.Single studies suggest that the presence of joint tenderness (n=189; positive likelihood ratio 11.4 (95% CI 5.9 to 22.0); negative likelihood ratio 0.2 (95% CI 0.0 to 1.2)) and joint effusion on ultrasound (n=127; positive likelihood ratio 8.4 (95% CI 4.1 to 17.1); negative likelihood ratio 0.2 (95% CI 0.1 to 0.3)) appear to be useful. Two promising clinical risk prediction tools were identified, however, their performance was notably lower when tested in external validation studies.DiscussionDifferentiating children with septic arthritis from non-emergent disorders of non-traumatic limp remains a key diagnostic challenge for emergency physicians. There is a need for prospectively derived and validated ED-based clinical risk prediction tools.

scholarly journals THU0346 SARC-F PERFORMANCE FOR SARCOPENIA SCREENING IN PATIENTS WITH SYSTEMIC SCLEROSIS

2020 ◽  
Vol 79 (Suppl 1) ◽  
pp. 404.1-404
Author(s):  
V. Hax ◽  
R. Santo ◽  
L. Santos ◽  
M. Farinon ◽  
M. De Oliveira ◽  
...  
Keyword(s):  
Systemic Sclerosis ◽  
Likelihood Ratio ◽  
Handgrip Strength ◽  
Pulmonary Function Tests ◽  
Positive Likelihood Ratio ◽  
Negative Likelihood Ratio ◽  
Youden Index ◽  
Routine Practice ◽  
Test Accuracy ◽  
European Working

Background:Because the method of diagnosing sarcopenia is complex and is considered to be difficult to introduce into routine practice, the European Working Group on Sarcopenia in Older People’s (EWGSOP) recommends use of the SARC-F questionnaire as a way to introduce assessment and treatment of sarcopenia into clinical practice1. Only recently, some studies have focused their attention on the presence of sarcopenia in systemic sclerosis (SSc) and there is no data about the performance of SARC-F in this population.Objectives:To test the diagnostic properties of the SARC-F questionnaire for sarcopenia screening in SSc patients.Methods:Cross-sectional study, including 94 SSc patients assessed by clinical evaluation, laboratory and pulmonary function tests. Sarcopenia was evaluated using the EWGSOP diagnostic criteria updated in 2019 (EWGSOP2): dual-energy X-ray absorptiometry, handgrip strength, and short physical performance battery (SPPB)1. Participants also completed the SARC-F questionnaire. The questionnaires’ performances were evaluated through receiver operating characteristic (ROC) curves and standard measures of diagnostic accuracy were computed using the EWGSOP2 criteria as the gold standard for diagnosis of sarcopenia.Results:Sarcopenia was identified in 15 (15,9%) SSc patients by the EWGSOP2 criteria. Area under the ROC curve of SARC-F screening for sarcopenia was 0.588 (95% confidence interval (CI) 0.482, 0.688) (figure 1). The results of sensitivity, specificity, positive likelihood ratio (PLR) and negative likelihood ratio (NLR) with the EWGSOP2 criteria as the reference standard were 35.71 [95% CI, 12.76-64.86], 81.01 (95% CI, 70.62-88.97), 1.88 (95% CI, 0.81-4.35) and 0.79 (95% CI, 0.53-1.19), respectively. The optimal cut-off point of SARC-F in our sample was ≥ 4 (Youden index: 0.21), the same cut-off point recommended in the literature2,3. Only 6 (40%) out of the 15 participants with sarcopenia were identified by the SARC-F questionnaire in our population. However, the SARC-F properly identified 4 out of 5 patients who had severe sarcopenia.Conclusion:This is the first study to evaluate the performance of SARC-F questionnaire for sarcopenia screening in patients with SSc. Although it appropriately identifies severe cases of sarcopenia, the SARC-F alone may not be an adequate screening tool in high-risk populations, such as SSc, that may benefit from early intervention and treatment.References:[1]Cruz-Jentoft AJ, Bahat G, Bauer J, et al. Sarcopenia: Revised European consensus on definition and diagnosis. Age Ageing. 2019;48(1):16-31.[2]Malmstrom TK, Morley JE. SARC-F: A simple questionnaire to rapidly diagnose sarcopenia. J Am Med Dir Assoc. 2013;14(8):531-532.[3]Ida S, Kaneko R, Murata K. SARC-F for Screening of Sarcopenia Among Older Adults: A Meta-analysis of Screening Test Accuracy. J Am Med Dir Assoc. 2018;19(8):685-689.Disclosure of Interests:Vanessa Hax: None declared, Rafaela Santo: None declared, Leonardo Santos: None declared, Mirian Farinon: None declared, Marianne de Oliveira: None declared, Guilherme Levi Três: None declared, Andrese Aline Gasparin: None declared, M Bredemeier: None declared, Ricardo Xavier Consultant of: AbbVie, Pfizer, Novartis, Janssen, Eli Lilly, Roche, Rafael Mendonça da Silva Chakr: None declared

scholarly journals Diagnostic accuracy of MALDI-TOF mass spectrometry for the direct identification of clinical pathogens from urine

Open Medicine ◽  
2020 ◽  
Vol 15 (1) ◽  
pp. 266-273
Author(s):  
Min Tang ◽  
Jia Yang ◽  
Ying Li ◽  
Luhua Zhang ◽  
Ying Peng ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Likelihood Ratio ◽  
Meta Analysis ◽  
Positive Likelihood Ratio ◽  
Negative Likelihood Ratio ◽  
Urine Samples ◽  
Direct Identification ◽  
Maldi Tof Ms ◽  
Maldi Tof ◽  
Tof Ms

AbstractMatrix-assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF MS) has become one of the most popular methods for the rapid and cost-effective detection of clinical pathogenic microorganisms. This study aimed to evaluate and compare the diagnostic performance of MALDI-TOF MS with that of conventional approaches for the direct identification of pathogens from urine samples. A systematic review was conducted based on a literature search of relevant databases. The pooled sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR) and area under the summary receiver operating characteristic (SROC) curve of the combined studies were estimated. Nine studies with a total of 3920 subjects were considered eligible and included in the meta-analysis. The pooled sensitivity was 0.85 (95% CI 0.79-0.90), and the pooled specificity was 0.93 (95% CI 0.82-0.97). The PLR and NLR were 11.51 (95% CI 4.53-29.26) and 0.16 (95% CI 0.11-0.24), respectively. The area under the SROC curve was 0.93 (95% CI 0.91-0.95). Sensitivity analysis showed that the results of this meta-analysis were stable. MALDI-TOF MS could directly identify microorganisms from urine samples with high sensitivity and specificity.

scholarly journals A reduced lymphocyte ratio as an early marker for predicting acute pancreatitis

2017 ◽  
Vol 7 (1) ◽  
Author(s):  
Xiuzhong Qi ◽  
Fangyong Yang ◽  
Haitao Huang ◽  
Yiqi Du ◽  
Yan Chen ◽  
...  
Keyword(s):  
Acute Pancreatitis ◽  
Likelihood Ratio ◽  
Disease Process ◽  
Positive Likelihood Ratio ◽  
Negative Likelihood Ratio ◽  
Roc Curves ◽  
Lymphocyte Ratio ◽  
Severity Prediction ◽  
Severity Grading ◽  
Mild Acute Pancreatitis

Abstract The early diagnosis and severity grading for acute pancreatitis (AP) are difficult to determine because of the complexity and differences in disease process. To date, few studies have investigated the role of lymphocyte ratio (LR) in AP. Therefore, the objective of the present study was to investigate the prognostic value of LR as an indicator in AP, as well as determine an optimal cut-off value for the severity prediction. There were two hundred four patients involved in this study, ninety-two of whom had severe acute pancreatitis (SAP). The LR was analyzed on admission and correlated with severity, which was determined using the Atlanta classification. The optimal cut-off value for LR was generated using receiving operator characteristic (ROC) curves. The results showed that the LR in the SAP group decreased significantly compared to the mild acute pancreatitis (MAP) group (8.82 vs. 13.43). The optimal cut-off value obtained from ROC curves was 0.081, with a sensitivity of 80.4%, a specificity of 53.3%, a positive likelihood ratio of 1.722, and a negative likelihood ratio of 0.368. In conclusion, the LR is obviously related to the condition of AP patients and is valuable for the differential diagnosis of SAP in early stages of AP.

scholarly journals A20 DIAGNOSTIC ACCURACY OF A LOW COST, WIDELY AVAILABLE TEST STRIP FOR PREDICTING A POSITIVE FECAL CALPROTECTIN TEST

2021 ◽  
Vol 4 (Supplement_1) ◽  
pp. 210-212
Author(s):  
R Trasolini ◽  
S Wong ◽  
B Salh
Keyword(s):  
Sample Size ◽  
Likelihood Ratio ◽  
Gold Standard ◽  
Low Cost ◽  
Positive Likelihood Ratio ◽  
Negative Likelihood Ratio ◽  
Rapid Test ◽  
Test Strip ◽  
Fecal Calprotectin ◽  
Type I

Abstract Background Fecal calprotectin is a non-invasive test of colonic inflammation used for monitoring inflammatory bowel disease activity and for risk stratifying non-specific colonic symptoms. Calprotectin is a leukocyte specific enzyme. A similar test, leukocyte esterase is used to detect leukocytes in urine and is widely available as a low-cost point-of-care test strip. We hypothesize that an unmodified version of the urine test strip would be highly accurate in predicting a positive fecal calprotectin test in a real world sample of patients. Aims To explore a low cost, rapid alternative to the fecal calprotectin test Methods All inpatient and outpatient stool samples tested for calprotectin by the Vancouver General Hospital laboratory from February 2020 to November 2020 were included prospectively. Samples were simultaneously tested for fecal leukocyte esterase using an unmodified Roche Cobas Chemstrip urinalysis test strip by central lab personnel. An identical aliquot was sent to LifeLabs for calprotectin as per standard protocol. All samples were suspended in buffer using established laboratory protocols prior to testing. Fecal leukocyte esterase results were reported as 0–4+ based on visual interpretation, calprotectin results were reported as mcg/g of stool. REB review and approval was obtained prior to data collection. Sensitivity, Specificity and AUROC were calculated using Microsoft Excel and JROCFIT. Results 26 samples were collected. Using a fecal calprotectin greater than 120 mcg/g as a gold standard an AUROC of 0.89 (SE= .06) was calculated. A leukocyte esterase reading of 2+ or greater had the best test characteristics based on ROC curve analysis. Using this cutoff, 21/26 samples were concordant, giving an accuracy of 80.8%, sensitivity of 90.9% and specificity of 73.3%. Positive likelihood ratio was 8.07 and negative likelihood ratio was 0.29. Assuming an AUROC of 0.8, the sample size N=26 is 90% powered (β=0.9) to predict the true AUROC within 0.1 with a type I error rate of .05 (α&lt;.05). Conclusions This study suggests application of a prepared stool sample to a urinalysis test strip gives a result highly predictive of a positive fecal calprotectin test. Further results are being collected prospectively to improve the robustness of these preliminary data. Secondary outcomes including comparison to endoscopy and biopsy results where available are planned if an adequate sample size can be accrued. Future studies justifying independent clinical use of leukocyte esterase would require a common gold standard comparator such as endoscopy. Fecal calprotectin testing is not universally insured and is not available as a rapid test strip. Use of fecal leukocyte esterase may reduce costs and shorten time to results if proven to be independently reliable. Funding Agencies None

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