Open AccessDiagnostic accuracy of faecal calprotectin in patients with active perianal fistulas
Author(s) -
Stevens Toer W,
D'Haens Geert R,
Duijvestein Marjolijn,
Bemelman Willem A,
Buskens Christianne J,
Gecse Krisztina B
Publication year - 2019
Publication title -
ueg journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.667
H-Index - 35
eISSN - 2050-6414
pISSN - 2050-6406
DOI - 10.1177/2050640619834464
Subject(s) - medicine , calprotectin , gastroenterology , receiver operating characteristic , predictive value , area under the curve , faecal calprotectin , diagnostic accuracy , predictive value of tests , area under curve , inflammatory bowel disease , disease , pharmacokinetics
Background Faecal calprotectin (FC) is a marker of mucosal inflammation. Objective The aim of this study was to determine the diagnostic accuracy of FC to (a) differentiate between perianal fistulizing Crohn's disease (pCD) and cryptoglandular perianal fistulas; and (b) detect mucosal inflammation in pCD. Methods Patients with active perianal fistulas who had FC measured and a complete ileocolonoscopy within 10 weeks were retrospectively included. Results Fifty‐six patients were included (pCD, n = 37) of whom 19 pCD patients exhibited ulcers. FC was significantly higher in pCD compared to cryptoglandular fistulas (µg/g) (708.0 (207.0–1705.0) vs 32.0 (23.0–77.0), p < 0.001). Area‐under‐the‐curve (AUC) value for FC receiver operating characteristic (ROC) statistics was 0.900. Optimal FC cut‐off was ≥ 150 µg/g. To differentiate pCD from cryptoglandular fistulas in the absence of luminal inflammation, optimal cut‐off remained ≥ 150 µg/g (AUC = 0.857, sensitivity = 0.81, specificity = 0.89, positive predictive value (PPV) = 93.8% and negative predictive value (NPV) = 70.8%). In pCD, FC was significantly increased in the presence of ulcers (1672.0 vs 238.0, p = 0.004). Optimal cut‐off was ≥ 250 µg/g (AUC = 0.776; sensitivity = 0.89, specificity = 0.56, PPV ‐ 68.0% and NPV = 83.0%). Conclusion FC discriminates pCD from cryptoglandular fistulas, even in the absence of intestinal ulcers. In active pCD, an elevated FC does not accurately predict the presence of ulcers and should be interpreted with caution.