Serum zonulin is elevated in IBS and correlates with stool frequency in IBS‐D

Background: Studies have shown increased intestinal permeability in irritable bowel syndrome. Validating serum biomarkers for altered intestinal permeability in irritable bowel syndrome will facilitate research and pathophysiology-based therapy. Objective: To measure serum zonulin and intestinal fatty acid binding protein levels in diarrhea-predominant irritable bowel syndrome and constipation-predominant irritable bowel syndrome and compare with healthy controls and celiac disease. Methods: = 42). Irritable bowel syndrome symptom severity was measured using the irritable bowel syndrome-symptom severity scale. Results: = 0.047 respectively). Conclusion: Serum zonulin is upregulated in irritable bowel syndrome and the levels are comparable to those in celiac disease. Zonulin levels correlated with severity of bowel habits in diarrhea-predominant irritable bowel syndrome. Intestinal fatty acid binding protein levels in irritable bowel syndrome patients were not increased suggesting no significant increase in enterocyte death.