Duodenal Hamartoma

Abstract

A 12-year-old boy presented with several months of intermittent early satiety, nonbilious vomiting, and weight loss. Duodenoscopy showed a narrowed pylorus (Fig. 1). Histology of antral and duodenal specimens was normal (no Helicobacter pylori). Abdominal ultrasound and computed tomography scan were unremarkable. Endoscopic ultrasound revealed abnormal thickening of the duodenal bulb wall with circumferential hypoechoic widening of the submucosal layer (Fig. 2). Fine needle biopsies displayed benign columnar epithelium only.Balloon dilatation of the proximal duodenum provided only temporary improvement. Laparascopy showed a hard and excentrically thickened proximal duodenum. Pyloroplasty was performed. Intraoperative biopsies revealed glandular elements surrounded by smooth muscle fibers, features suggestive of myoepithelial hamartoma (Figs. 3 and 4). The patient remains symptom free 12 months later.Beyond infancy, pediatric gastric outlet obstruction is rare. Incidence is reported to be as low as 1:100,000 (1). Causes of congenital narrowing of antrum and duodenum must be distinguished from acquired conditions such as peptic ulceration, inflammatory bowel disease, caustic injury, or neoplasms (2). Hamartomas remain an unusual cause of upper gastrointestinal obstruction, hemorrhage, and intussusception (3,4). Conventional imaging and endoscopy are nondiagnostic (1), and persistent symptoms warrant operative exploration. Transmural biopsies are crucial for diagnosis. Pyloroplasty leads to remission of symptoms of this otherwise benign condition.