The Accuracy of a Home-performed Faecal Calprotectin Test in Paediatric Patients With Inflammatory Bowel Disease.

ABSTRACT

OBJECTIVES: Owing to the invasiveness of endoscopy, the use of biomarkers, especially faecal calprotectin (FC), has become standard for remission assessment. This study aimed to compare the accuracy for detection of endoscopic activity using recently developed FC home test using smartphone application (FC-IBDoc) against standard enzyme-linked immunosorbent assay (ELISA). METHODS: In all, 102 consecutive observations (89 participants) were included in prospective observational study. FC-IBDoc was performed parallelly with FC-ELISA in paediatric patients with inflammatory bowel disease indicated for endoscopy. Both tests were performed by trained staff. Mucosal healing was defined using Simple Endoscopic Score for Crohn disease (CD) ≤2 in patients with CD (n = 44), ulcerative colitis (UC) Endoscopic Index of Severity ≤4 in patients with UC (n = 27) and Rutgeerts score i0 and i1 without colon involvement in patients with CD after ileocaecal resection (n = 19). RESULTS: Out of 102 endoscopic findings 23 were assessed as mucosal healing. We found an association of the mucosal healing scores of the entire group both with FC-ELISA (P = 0.002) and FC-IBDoc (P = 0.001). The area under the receiver operating characteristic curve for FC-ELISA was 0.883 (95% confidence interval 0.807-0.960), with optimal cut-off at 136.5 µg/g. The area under the receiver operating characteristic curve for FC-IBDoc was 0.792 (95% confidence interval 0.688-0.895) with optimal cut-off at 48 µg/g. The FC-ELISA was more accurate than FC-IBDoc when tested by a Delong test (P = 0.023). CONCLUSIONS: Standard FC-ELISA for FC evaluation is more reliable predictor of mucosal healing than the FC-IBDoc in paediatric patients with inflammatory bowel disease. The cut-off values for both tests were incongruous.