Introduction

Inflammatory bowel disease is an idiopathic disorder characterized by repeated relapses and remissions. Endoscopy, the gold standard for diagnosis and monitoring, is time consuming, expensive and invasive. Fecal calprotectin has been suggested as a surrogate marker to assess intestinal inflammation and predict disease relapse. Published evidence regarding the utility of fecal calprotectin as an indicator of clinical activity and endoscopic severity in patients with inflammatory bowel disease is not unambiguous.

Aims & Methods

The aim of this study was to determine the use of fecal calprotectin as a predictor of clinical activity and endoscopic severity in patients with inflammatory bowel disease.
Methods: Patients fulfilling selection criteria were recruited for the study. Clinical examination findings, laboratory investigations and fecal calprotectin levels were documented as per proforma. Endoscopic and clinical severity were measured by Simple Endoscopic Score and Crohn’s Disease Activity Index for Crohn’s disease and by Ulcerative Colitis Endoscopic Index of Severity score and Simple Clinical Colitis Activity Index for Ulcerative Colitis .Lab investigations and calprotectin were repeated after six months and compared with endoscopic and clinical activity indices.

Results

Fecal calprotectin correlated with Crohn’s Disease Activity Index both at first visit and follow up (r-0.689, p-0.016)(r-0.425, p-value <0.05). The sensitivity and specificity of calprotectin in detecting active disease and remission at first visit were 93.8% and 80% respectively (AUC-0.869). At follow up, the sensitivity and specificity were 80% and 93.3% respectively (AUC-0.867). In Ulcerative colitis , Simple Clinical Colitis Activity Index score correlated with fecal calprotectin levels at first visit and follow up. (r-0.231 / 0.387, p-value 0.001/0.001). The sensitivity of calprotectin in detecting active disease and remission in ulcerative colitis was 92.6% and specificity was 83.3%. AUC was 0.88. At follow up, the sensitivity of fecal calprotectin in detecting active disease and remission was 89.9% and the specificity was 87.0% ; AUC was 0.879.

Conclusion

Fecal calprotectin levels show significant correlation with clinical and endoscopic activity indices in patients of inflammatory bowel disease. Therefore, calprotectin levels in stool could be used as a surrogate marker for monitoring mucosal status as well as predicting endoscopic remission in these patients.

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