Objective: Faecal calprotectin (FC) is the most relevant noninvasive biomarker for monitoring inflammatory status, response to treatment and for predicting clinical relapse in ulcerative colitis (UC). The aim of this study was to evaluate the role of FC in predicting both clinical/endoscopic activity and clinical relapse in a large UC patient cohort.
Patients and methods: A two-phase prospective study was carried out. In the first phase, the relationship between FC and clinical/endoscopic activity was evaluated. In the second phase, a cohort of asymptomatic patients with endoscopic mucosal healing was followed up using clinical and FC level determinations.
Results: One hundred and twenty-one UC patients were enrolled. The FC concentrations were directly correlated with both clinical and endoscopic activity (r=0.76 and 0.87, respectively, P<0.05) and were capable of differentiating between different degrees of endoscopic severity (P<0.01). An FC cut-off value of 110 μg/g was highly predictive (95%) of endoscopic activity. Seventy-four patients in clinical remission with mucosal healing were followed up for a year or until relapse and 27% developed a clinical relapse. The FC concentration of nonrelapsed patients (48 μg/g) versus relapsed patients (218 μg/g) was significantly different (P<0.01). An FC cut-off value of 193 μg/g had an accuracy of 89% in predicting clinical relapse. High FC levels were associated with clinical relapse using survival analysis and multivariate analysis.
Conclusion: Our data strongly support the use of FC for staging the activity of disease, predicting relapse and leading decision-making in a UC setting.