Aim: To investigate the utility of routine endoscopic distal duodenal biopsy in patients with Irritable Bowel Syndrome (IBS) for the diagnosis of Celiac Disease (CD). Method: This study was conducted at the outpatient Department of Gastroenterology at the Institute of Medicine, Tribhuvan University, Kathmandu, Nepal. One hundred patients with IBS selected by Rome III Criteria were prospectively evaluated from April 2015 through March 2016. Esophagogastroduodenoscopy (EGD) was performed on all patients, with four-quadrant distal duodenal biopsies obtained from each patient. The biopsy sections were studied for Marsh-type histology, a histology characteristic of CD. Patients with Marsh-type histology had Immunoglobulin-A anti-tissue transglutaminase (IgA anti tTG) serology ordered, were recommended to start a gluten-free diet (GFD), and were followed up in clinic in 3-6 weeks. The prevalence of CD (defined as Marsh histology grade I-III with serology positive responding to GFD) was calculated in patients with IBS as a whole and among IBS subtypes. Statistical analysis was done using SPSS version 19 software (Chicago, IL, USA). Results: Of the 100 IBS patients evaluated, 50 patients had abnormal duodenal histology. Among these 50 patients, 13 had Marsh-type histology, and the remaining 37 had non-specific duodenitis. Of the 13 patients with Marsh-type histology, 4 were seropositive for CD and 9 were seronegative. The overall prevalence of CD was 4%. All 4 seropositive and 2 out of 9 seronegative patients responded to GFD in 3 to 6 weeks. Conclusion: Routine endoscopic distal duodenal biopsy is useful for the diagnosis of CD in patients with IBS as it could also detect the disease in patients with negative celiac serology.

irritable bowel syndrome, celiac disease, HLA-DQ2/DQ8, marsh classification, gluten free diet