P029 ACCURACY OF FECAL CALPROTECTIN IN DETECTING SMALL BOWEL CROHN’S DISEASE: A META-ANALYSIS AND SYSTEMATIC REVIEW

Abstract

Identifying active small bowel Crohn’s Disease (CD) is often challenging due various reasons. The location of Crohn’s disease and often the disease process itself make direct visualization difficult. Fecal calprotectin (FCP) is a well-established marker of mucosal inflammation. Several studies have confirmed FCP’s utility in colonic inflammation; however, the diagnostic accuracy in active small bowel inflammation had yet to be established. The aim of the present study is to update the previous meta-analysis of FCP and its diagnostic accuracy in detecting active small bowel Crohn’s disease. A comprehensive search was performed using PubMed/OVID studies. Studies from 2010 until 2018 addressing patients with suspected or known CD and evaluated with noninvasive testing with FCP and confirming disease with video capsule endoscopy or imaging were included. Studies in which a 2 X 2 table with true positives, false negatives, false positives and true negative values could be constructed were included. Meta-analysis for the diagnostic accuracy of fecal calprotectin in diagnosing active small bowel CD was performed by calculating pooled estimates of sensitivity, specificity, likelihood rations, and diagnostic odds ratios. Pooling was conducted by both fixed and random effects models. Data was extracted from 17 studies which met the inclusion criteria. In CD patients, pooled sensitivity of fecal calprotectin was 76.50% (95% CI: 73.00 – 79.00) in diagnosing small bowel Crohn’s disease. Fecal calprotectin had a pooled specificity of 71.10% (95% CI: 68.00 – 73.00) for detecting active small bowel Crohn’s disease. The diagnostic odds ratio, of having active small bowel disease with elevated FCP was 12.28 (95% CI: 6.55 – 23.01). The positive likelihood ratio of FCP was 3.093 (95% CI: 2.16 – 4.41), and the negative likelihood ratio was 0.30 (95% CI: 0.21 – 0.43). Fecal calprotectin has moderate diagnostic accuracy for detecting active small bowel CD. Our results suggest a fecal calprotectin of at least 50 µg/g has moderate sensitivity and specificity. These values are proportional to the fecal calprotectin level.