P180. A new rapid test for fecal calprotectin (FC) predicts mucosa healing in Crohn's disease (CD)
T. Lobaton Ortega1, F. Rodriguez-Moranta1, J. Guardiola1, E. Sanchez-Pastor1, L. Rodriguez Alonso1, S. Ruiz-Cerulla1, A. Lopez-Garcia1
1Hospital Universitari Bellvitage, Gastroenterology, Barcelona, Spain
Background: C Reactive Protein (CRP) is the most frequently used biomarker in CD is despite its lack of response in more than 20% of patients with active disease. Previous studies with Enzyme-linked immunosorbent assay (ELISA) have shown that FC has a more accurated correlation with endoscopic activity.
However, there is scarce data on the accuracy of rapid tests for FC (quantitative test based on inmunocromatography wich gives results in 12 minutes), which could make more feasible its use in clinical practice.
Aims and Methods: Aims: To evaluate the capacity of FC to discrimine endoscopic activity from mucosa healing with both tests: ELISA and rapid tests. To show correlation between both techniques of FC measurement. To assess correlation of endoscopic activity with FC compared to CRP and rest of markers.
Methods: Setting: Inflammatory Bowel Disease Unit from a referral hospital from Barcelona (Hospital de Bellvitge). Design: transversal and prospective. Patients: 46 EC patients referred for colonoscopy between December 2010 and July 2011.
Variables: Crohn Disease Activity Index (CDAI), HarveyBradshaw (HB) index, serological biomarkers (CRP, ESR, leucocytes and platelets), Crohn Disease Endoscopic Severity Index (CDEIS), Simplified Endoscopic Score for CD (SES-CD), FC determined by Bühlmann ELISA® and Bühlmann QUANTUM BLUE®.
Results: We obtained a very good correlation (r = Pearson rank correlation coefficient) between different indexes: CDEIS with SES CD with r = 0.968 (p < 0.001); CDAI with HB with r = 0.83 (p < 0.001), as well as between both tecniques for FC mesurement (r = 0.88; p < 0.001).
Endoscopic activity correlated closest with FC (Pearson rank correlation coefficient r = 0.807 p < 0.001), followed by CRP (r = 0.650, p < 0.001), clinical activity (CDAI) (r = 0.442, p = 0.004), ESR (r = 0.397, p = 0.015), platelets (r = 0.365, p = 0.015) and leukocytes (r = 0.146, p = 0.345).
FC levels (CF (Median ± SD) could discriminate between endoscopic activity (CDEIS ≥3, FC: 1764.8±972.2) and mucosa healing (CDEIS <3, FC: 271.1±351.53 p < 0.001).
In the multivariate analysis, only FC was an independent predictive variable of endoscopic activity. The accuracy to predict MH, defined by area under the curve (AUC), was of 0.92 with ELISA and 0.90 with rapid tests.
Conclusions: FC is more accurated than CRP and the rest of biomarkers to predict mucosa healing.
The good correlation that rapid tests presents with ELISA enables its use in clinical practice in order to take fast and appropiate decisions.