Rapid fecal calprotectin test for prediction of mucosal inflammation in ulcerative colitis and Crohn disease: a prospective cohort study.

Abstract

INTRODUCTION Fecal calprotectin (FC) is a well‑establishedbiomarker of intestinal inflammation in Crohndisease (CD) and ulcerative colitis (UC). However, standard laboratory methods are time‑consumingandnot always useful in clinical practice. OBJECTIVES We analyzed the efficacy of a rapid bedside FC test to detect disease flares in a hospitalsetting. We also assessed the influence of disease location on the diagnostic accuracy of FC. PATIENTS AND METHODS This prospective study included 140 patients (46 with UC; 94 with CD). FCwas measured by an enzyme‑linkedimmunosorbent assay (ELISA) and by the rapid Quantum Blue®test. Endoscopic activity was assessed using the Mayo endoscopic subscore or the Simple EndoscopicScore for Crohn's Disease (SES‑CD). RESULTS FC levels highly correlated with endoscopic activity in CD (area under the receiver operatingcharacteristic curve [AUC], 0.83) and UC (AUC, 0.80), with the cut‑offvalues of 238.5 μg/g and499 μg/g, respectively. FC levels increased dynamically even with early signs of inflammation both in CD(SES‑CD,4-10 vs 0 points: 252 vs 100.0 μg/g; P = 0.02) and UC (Mayo subscore, 1 vs 0 points: 323.3vs 100.0 μg/g; P <0.001). In UC, FC levels were lower in proctitis than in left‑sidedUC and pancolitis(340.0, 500.0, and 421.5 μg/g, respectively), but the differences were not significant. In CD, lower FCvalues were observed in isolated small bowel disease. CONCLUSIONS FC levels increased dynamically even with mild signs of intestinal inflammation. The rapidQuantum Blue® test presents a potential alternative to the time‑consumingELISA, because its diagnosticaccuracy is not influenced by disease location. It may be useful in the hospital setting, providing fasterdiagnosis and allowing cost reduction by lowering the number of endoscopic procedures.