Low fecal calprotectin predicts clinical remission in Crohn's disease patients: the simple answer to a challenging question

Background and aim: Fecal calprotectin (FC) is a noninvasive marker of intestinal inflammation. Predicting relapses in Crohn’s disease (CD) patients can allow earlier changes in therapy. The aim of this study was to evaluate the role of FC in predicting relapse in CD patients in clinical remission within six months follow-up.

Methods: Patients with CD who were in clinical remission at least ≥3 months were included in this study. The first FC sample during the remission period was evaluated and was used as the baseline value. Relapse was defined as an unexpected escalation in therapy, hospitalization or need for surgery for active CD. The accuracy and optimal cutoff FC values for predicting clinical relapse at six months were assessed by the area under the ROC curve (AUC).

Results: One hundred and forty-four patients were evaluated, with mean age of 38.4 years. Of these, 13 (9%) had a relapse during the follow-up period. The mean FC value was significantly lower for non-relapsers (203.2?μg/g) than for relapsers (871.3?μg/g), p?<?.001. The AUC for predicting relapse by using FC values was 0.924. The optimal cutoff FC value to predict relapse was 327?μg/g; with values of sensitivity, specificity, negative predictive value and positive predictive value were 92.3%, 82.4%, 99.1% and 34.3%, respectively.

Conclusions: FC is more useful in predicting remission maintenance than relapse in patients with CD in clinical remission. Values of FC ≤327?μg/g can exclude relapse at least at six months follow-up period.