Duodenal Villous Atrophy and Diarrhea Associated with Chronic Olmesartan Intake

Olmesartan is an angiotensin II receptor blocker (ARB) approved for the treatment of hypertension since 2002. Olmesartan-associated enteropathy (OAE), first described in 2012 by Rubio-Tapia, has seldom been considered as a diagnosis in patients with villous atrophy and negative serology for celiac disease. The clinical presentation could be extremely heterogenous. In contrast to celiac disease, there is no response to a gluten-free diet. The exact mechanism of intestinal injury still remains unknown. The histological pattern, at the upper gastrointestinal endoscopy, usually reveals a variable degree of villous atrophy and a moderate infiltration of lymphocytes at mucosal level. Symptoms usually improve upon olmesartan discontinuation and the repeat endoscopy could demonstrate complete resolution of inflammatory change with normal villous architecture. The differential diagnosis for this kind of clinical and pathological features include celiac disease, tropical sprue, autoimmune enteropathy, inflammatory bowel disease, and drug induced enteropathy. With this background, we report the case of a patient with a clinical picture compatible with seronegative celiac disease and symptoms that rapidly improved clinically and histologically after olmesartan discontinuation. In conclusion, although this condition is rare, physicians should be consider this medication in the differential diagnosis of this enteropathy.