The role of salivary calprotectin in monitoring Crohn's disease: A cross-sectional study.

Abstract

Background and study aims: Noninvasive biomarkers are needed to monitor disease activity in inflammatory bowel disease, as current methods-including blood tests, endoscopy, imaging, and fecal calprotectin-are invasive, costly, or burdensome. This study explored salivary calprotectin as a potential biomarker for Crohn's disease activity.

Patients and methods: This was a cross-sectional exploratory study. Unstimulated saliva was collected from patients with an established diagnosis of Crohn's disease and matched healthy controls. Disease activity was determined via the Crohn's disease Activity Index. Salivary calprotectin was measured in 20 μl saliva samples using enzyme-linked immunosorbent assay.

Results: Samples were collected from 42 patients with Crohn's disease (mean age 36.3 ± 14.2 years, 52.4 % male) and 41 age-matched healthy controls (mean age 38 ± 13.4 years, 58.5 % male). For patients with Crohn's disease, the median salivary calprotectin level was 0.08 (IQR 0.05-0.14) ug/ml compared to 0.06 (IQR 0.03-0.13) ug/ml in healthy controls (p = 0.161). Among patients with Crohn's disease, levels were similar in remission (0.10, IQR 0.05-0.15 μg/mL) and active disease (0.07, IQR 0.03-0.10 μg/mL; p = 0.091). No correlation was observed between salivary calprotectin and Crohn's disease activity index scores (Spearman's r = -0.136, p = 0.392).

Conclusions: Salivary calprotectin did not distinguish patients with Crohn's disease from healthy controls or correlate with disease activity. While noninvasive, it does not appear to be a clinically useful biomarker for monitoring Crohn's disease. Further research may clarify its role in inflammatory bowel disease or identify more promising biomarkers.