Rare Case of Olmesartan Induced Enteropathy

Olmesartan (brand name Benicar) is an antihypertensive drug clinicians commonly use to treat high blood pressure. Olmesartan induced enteropathy (OSE) is a rare entity that authors first identified in 2012. The etiological basis of OSE remains unclear, although authors have suggested that this condition could be due to alternations in cell mediated immune responses induced by the drug. The objective of the case report is to describe a patient who presented with diarrhea and was eventually diagnosed with OSE. A female patient in her later 60s presented to an emergency room after two recent hospitalizations with profound diarrhea, generalized weakness and weight loss. She underwent a diagnostic workup including endoscopy and colonoscopy. The patient's endoscopy with duodenal biopsy revealed villous atrophy with attenuated and blunted villi with intraepithelial CD3 positive T lymphocytes, suggestive of gluten-induced enteropathy. When the patient's symptoms did not improve after the authors placed her on a gluten free diet for a few days, they further investigated her for secretory diarrhea, including Gastrin, Somatostatin and Vasoactive Intestinal Peptide lab values that they found to be within normal limits. Due to the patient's lack of improvement with initial treatment, the authors suspected OSE and stopped her olmesartan and the patients' symptoms gradually improved in three weeks.