P274. Close monitoring of CRP and fecal calprotectin levels to predict relapse in Crohn's disease patients. A sub‑analysis of the STORI study
N. de Suray1, J. Salleron2, G. Vernier-Massouille1, J.C. Grimaud3, Y. Bouhnik4, D. Laharie5, J.‑L. Dupas6, H. Pillant7, L. Picon8, M. Veyrac9, M. Flamant10, G. Savoye11, R. Jian12, M. De Vos13, E. Piver8, J.Y. Mary14, J.‑F. Colombel15, E. Louis16
1Hôpital Claude Huriez, Department of Hepato-Gastroenterology, Lille, France; 2Lille University Hospital, Epidemiology Unit, Lille, France; 3Marseille North Hospital, Dept. of Hepagastroenterology, Marseille, France; 4Beaujon Hospital, Department of Gastoenterology, Clichy, France; 5Hôpital Haut-Lévêque, Service Gastroenterologie, Pessac, France; 6Amiens University Hospital North Hospital, Dept. of Hepagastroenterology, Amiens, France; 7Hôpital Henri Mondor, Créteil, France; 8CHRU Trousseau, Tours, France; 9Hôpital Saint-Eloi, Montpellier, France; 10CHU Hotel Dieu, Nantes, France; 11Hôpital Charles Nicolle, Department of Gastroenterology, Rouen, France; 12Hôpital Européen Georges Pompidou, Paris, France; 13Ghent University Hospital, Department of Gastroenterology, Ghent, Belgium; 14DBIM, Hôpital Saint Louis, Inserm U 717, Paris, France; 15Centre Hospitalier Universitaire de Lille, Hôpital Claude Huriez, Lille, France; 16University of Liège and CHU Liège, Department of Gastroenterology, Liège, Belgium
Background: In Crohn's disease (CD), predicting relapse by measuring non-invasive biomarkers could allow early treatment adaptation. Several studies have shown a correlation between intestinal inflammation and serum C‑reactive protein (CRP) or fecal calprotectin (Calpro) levels. However, few data exists about the usefulness of close monitoring of these two biomarkers to predict relapse of CD in the short term.
The aim of our study was to assess the value of close monitoring of CRP and Calpro levels to predict relapse of CD after infliximab (IFX) discontinuation.
Methods: Luminal CD patients treated for at least one year with scheduled IFX combined with immunosuppressant (IS) and in stable remission without steroids for at least 6 months were prospectively recruited into the STORI study. IFX was discontinued at baseline and IS treatment was kept at a stable dose over the study period. CRP and Calpro levels were measured every 2 months until 18 months of follow-up or until clinical relapse. For each patient, median values of CRP and Calpro were computed and compared between relapsers and non-relapsers by a Mann-Whitney test. Relapse rate was analysed using the Cox model (time dependent) for CRP and Calpro.
Results: 113 patients were included and analyzed. Among them, 51 presented a relapse after a median follow-up of 10 months. 721 CRP and 675 Calpro measurements were performed with a median of 6 measurements/patient for both markers. During follow-up, we found a high variability of CRP and Calpro, regardless of the occurrence of relapse. However, the medians of median concentrations of CRP and Calpro per patient were higher in relapsers than in non-relapsers (3.9 vs 2.8 mg/l, P = 0.07; 151 vs 52 µg/g, P = 0.001). Using time-dependent Cox model, values of CRP >5 mg/l and Calpro >250 µg/g were associated with relapse in the short term with a HR of relapse (95% confidence interval) of 4.2 (1.9 to 9.2), p = 0.001 and 6.5 (2.7 to 15.6), p < 0.001, respectively.
Conclusions: After discontinuation of IFX in CD patients, elevated levels of CRP and Calpro were associated with an increased risk of short term relapse, even if there was a high variability of both markers during follow-up. Other models taking into account the relative and sustained changes of these markers should improve the accuracy for prediction of relapse.