RESUMEN
Brunner's gland hyperplasia (BGH) is a diagnostic challenge where in the pathophysiology and natural history remain poorly understood. This Case Report describes BGH arising at the ampulla of Vater, causing abdominal pain and vomiting in a 46-year-old man. Owing to the inconclusive nature of imaging studies and suspicious intraoperative findings, a Whipple resection was performed without any complications. Histological analysis showed that the obstructing lesion was BGH, with no evidence of malignancy. This is only the second such case of its kind at the ampulla of Vater to be reported. In addition, we present the previously unreported endoscopic ultrasound findings. The subsequent literature review focuses on the pathophysiology, clinical presentation, diagnosis and management of BGH.