A case report of olmesartan-associated sprue-like enteropathy: Diagnosis and healing confirmed by capsule endoscopy.

Herein, we describe a case of olmesartan-related sprue-like enteropathy in which improvement in villous atrophy was confirmed by small-bowel capsule endoscopy (CE). We successfully treated a 66-year-old man with a chief complaint of loose diarrhea. The patient had persistent watery diarrhea 10 times a day and experienced a weight loss of 9 kg in 3 months. An abdominal computed tomography scan showed fluid retention in the small intestine. Blood test results revealed no inflammatory reaction. Esophagogastroduodenoscopy detected villous atrophy in the stomach and duodenum. Moreover, small-bowel CE showed villous atrophy in about two-thirds of the small intestine. Based on other examinations, hyperthyroidism, intestinal tuberculosis, intestinal amyloidosis, and intestinal malignant lymphoma were ruled out. Therefore, the patient was suspected of having an olmesartan-related sprue-like disease. Early after discontinuation of medication, diarrhea symptoms improved, and a repeat CE indicated improvements in small intestinal villous atrophy. Since the patient had been administered olmesartan for a long time and CE showed villous atrophy throughout the small bowel, we suspected him of having the olmesartan-associated sprue-like disease. The findings of gastric mucosa atrophy on esophagogastroduodenoscopy may lead to an early diagnosis of this disease. Olmesartan-related sprue-like enteropathy should be considered as a differential diagnosis in patients with chronic severe watery diarrhea.