P249 Serum calprotectin is useful to confirm Inflammatory Bowel Disease activity but is not effective to predict relapse.

Veyrard, P.(1);Roblin, X.(2);Mao, R.(3);Nancey, S.(4);waeckel, L.(5);Berger, A.E.(6);Williet, N.(7);Bastide, L.(7);Barrau, M.(7);tournier, Q.(7);Paul, S.(6);

(1)CHU SAINT-ETIENNE, gastro enterology, Saint-Priest-en-Jarez, France;(2)chu saint etienne, gastro enterology, Saint-Priest-en-Jarez, France;(3)Hospital of Sun Yat-sen University, Inflammation and immunity, guangzhou, China;(4)chu Lyon sud, Gastroenterology, Lyon, France;(5)chu st etienne, immunology, Saint etienne, France;(6)CHU Saint etienne, Immunology, Saint Etienne, France;(7)CHU saint etienne, Gastroenterology, Saint etienne, France;

Background

Serum calprotectin (SC), a novel biomarker of inflammatory bowel diseases (IBD), has been recently investigated with conflicting results. The purpose of this study was to assess the ability of SC for predicting disease relapse in patients with IBD treated by biologic therapies, and to evaluate the correlation between SC and clinical and endoscopic relapse and with other biomarkers including fecal calprotectin (FC) and C-reactive protein (CRP).

Methods

All consecutive IBD patients in deep remission (clinical and endoscopic or imaging remission) were recruited in this prospective study and followed 12 months. Blood and stool samples were collected for SC, serum CRP and FC measurement.  SC was measured the day of inclusion (baseline, D0), 3 months (M3) and 6 months (M6) later and in case of relapse during the study period. Relapse was defined as clinical, biomarkers, or endoscopic/imaging activity. So, firstly, we looked at evolution of SC before relapse to analyze a predicting value of loss of response (LOR). We also compared SC for patients with active IBD and those with symptoms without inflammation.

Results

Among the 119 patients included, 54 (46.4%) patients experienced a disease relapse during follow-up. When we looked at the kinetic of SC during follow-up, median SC levels did not increase in patients who relapsed: 3.15 µg/l at baseline, 3.38 µg/l at M3, 3.33 µg/l at M6 and 3.99 µg/l in case of relapse (p=0.63).

We compared SC during relapse with patients in endoscopic remission but clinical symptoms which defined secondary Irritable Bowel Syndrome, we found that SC levels were higher in active IBD and similar between the groups of patients with IBS or deep remission  (3.05µg/l IBS vs 2.99µg/l remission vs 5.1µg/l for relapsers, p=0.04). In patients with clinical symptoms, SC presents a good predictive value for relapse. (AUROC 0.764, IC95: 0.68-0.88), giving a sensitivity of 72% with a specificity of 77%, using a cut-off value of 4.45mg/ml. A weak, but significant correlation was found between SC and FC levels (r=0.35, P= 0.001). A combined score with CRP, FC and SC didn’t improve its diagnostic accuracy.

Conclusion

SC was significantly higher in patients with relapse compared to those in endoscopic remission with or without clinical symptoms. It seemed that it permit to oppose patients with active IBD and those with symptoms of IBS. However, it failed to predict relapse.