Olmesartan-Induced Enteropathy: A Report of an Unusual Cause of Chronic Diarrhea.

Olmesartan, an angiotensin II receptor blocker indicated in the treatment of hypertension, has been associ-ated with a seronegative sprue-like enteropathy that should be considered in the differential diagnosis of patients with unexplained chronic diarrhoea. It typically presents with severe chronic diarrhoea, considerable weight loss, and villous atrophy on biopsy and may be difficult to recognize because of its clinical and histological similarities to other clinical entities. Practically, discontinuation of the drug leads to dramatic recovery of the symptoms. We report a 76-year-old Caucasian female who was admitted to our hospital with complaints of chronic diarrhea and significant weight loss. Medical history was notable for hypertension being treated with olmesartan. Initially, investigation for all potential infectious causes and celiac disease was negative. Both upper and lower endoscopy was performed with duodenal biopsies revealing total villous atrophy and colonic biopsies showing lymphocytic colitis. In the presence of negative serology for celiac disease and after a thorough review of the patient's medications, olmesartan in-duced-enteropathy was the most possible diagnosis. Olmesartan was discontinued and the symptoms rapidly resolved. A follow-up done a few months later showed no recurrence of the symptoms. In olmesartan-associated enteropathy, discontinuation of olmesartan results in immediate clinical recovery. Although rare, it is considered an emerging and underdiagnosed enteropathy. This case report illustrates the need for a thorough medication history evaluation and regular review during workup. We aim to increase the awareness of olmesartan-induced enteropathy among clinicians and gastroenterologists. We hope it will add to the current literature and help to understand this rare phenomenon in order to avoid unnecessary testing.