P226 Systematic review with meta-analysis of individual data: impact of cut-off values on the performance of faecal calprotectin to detect endoscopic recurrence after intestinal resection in patients with Crohn’s disease
J. Kirchgesner1, G. Boschetti2, A. Buisson3, T. Yamamoto4, E. Domenech5, S. Nancey2, L. Peyrin-Biroulet6, M. Uzzan*7
1Saint-Antoine Hospital, Paris, France, 2CH Lyon-Sud, Lyon, France, 3CHU Estaing, Clermont-Ferrand, France, 4Yokkaichi Hazu Medical Center, Yokkaichi, Japan, 5Hospital Universitari Germans Trias i Pujol, Badalona, Spain, 6CHU Nancy, Vandoeuvre Les Nancy, France, 7Hopital Beaujon, Clichy, France
Endoscopic assessment of post-operative recurrence (ePOR) is recommended within 1 year after ileocaecal resection (ICR) for Crohn’s disease (CD) as it accurately predicts clinical course and guides medical management. However, endoscopy is an invasive procedure and a frequent endoscopic monitoring is not feasible in routine care. Although faecal calprotectin (FC) has been studied and validated as a useful tool in CD in several settings, it is still not well defined how thresholds impact the performance of FC to detect ePOR. In this meta-analysis including cohort studies of CD patients who underwent intestinal resection, we aimed to determine how cut-off values influence the performance of the FC to detect ePOR.
A systematic search using PubMed and EMBASE databases was performed independently by two authors. The search strategy used the following terms: calprotectin, Crohn’s, Ileocaecal, postop*, intestinal resection. Studies performed in adult patients with CD who underwent intestinal resection, in which FC (expressed in µg/g) was evaluated as a surrogated marker of ePOR (defined as a Rutgeers score ≥ i2 or i2b) were included. The extracted data were pooled using a hierarchical summary receiver-operating curve model. We assessed the sensitivity, specificity and positive and negative likelihood ratios for FC cut-offs ranging from 10 µg/g to 500 µg/g.
A total of 158 titles and abstracts were identified. After selection, 11 studies remained for further analysis. A total of 892 patients were included, among whom 421 (47.2%) developed ePOR. Eight studies were designed as cross-sectional studies with either a retrospective or a prospective selection of patients. Two studies were a sub analysis of randomised control trials (POCER and TOPPIC). For FC cut-offs set at 50 µg/g and below, the sensitivity to detect ePOR was at least of 0.92. Specifically for 50 µg/g, it was estimated at 0.92 (95% confidence interval (95CI) [0.85–0.96]). On the other hand, a cut-off at 250 µg/g or more provided a specificity of at least 0.90 to detect ePOR (0.90 95CI[0.79–0.96] for 250 µg/g).
Sensitivity and specificity of FC to detect ePOR according to cut-off.
After ICR for CD, FC outside a 50–250 µg/g range could avoid unnecessary colonoscopies, as it allows the detection with a high probability of endoscopic remission (< 50 µg/g) or ePOR (>250 µg/g).