Objective: Fecal calprotectin (FC) is a promising marker for discrimination of irritable bowel syndrome (IBS) and inflammatory bowel disease (IBD). The search for non-invasive tools for identification of ulcerative colitis (UC), in IBD patients, is still an issue. We aimed to evaluate if combination with other parameters improves the predictive value of FC in UC diagnosis.

Material and Method: Patients who underwent FC analysis and that were diagnosed with IBS (n=121) and IBD (UC, n=186 and Crohn’s disease (CD), n=101) were selected for this methodologic study. Logistic regression analysis was used to model the prediction of UC using FC individually or in combination with fecal occult blood (FOB), lymphocyte percent (LP) and neutrophil percent (NP) values.

Results: FC, FOB, LP, and NP were significantly different in UC patients compared to both CD and IBS patients. The AUCs of “FC+FOB+LP+NP” and “FC+FOB” models were significantly greater than that of FC for predicting UC in the entire patient population (AUC=0.789, 0.774 and 0.705, respectively, p<0.05) and in IBD patients (AUCs=0.755, 0.708 and 0.607, respectively, p<0.05). AUCs of “FC+LP”(0.800) and “FC+LP+NP” (0.800) models were significantly greater compared to that of FC (0.756) in predicting IBD in the entire patient population (p<0.05).

Conclusion: The combination of inflammatory blood markers and stool biomarkers may provide valuable, non-invasive tools for the identification of UC in IBS and IBD patients.

Fecal calprotectin Fecal occult blood Ulcerative colitis Inflammatory bowel disease Irritable bowel syndrome Lymphocyte percent Neutrophil percent