Late-onset hypertrophic pyloric stenosis with gastric outlet obstruction: case report and review of the literature.

We report late-onset hypertrophic pyloric stenosis in a 17-year-old female. She presented with abdominal pain and an episode of upper gastrointestinal hemorrhage and subsequently developed gastric outlet obstruction. Work-up revealed circumferential pyloric thickening, delayed gastric emptying, and a stenotic, elongated pyloric channel. Biopsies showed benign gastropathy, negative for Helicobacter pylori, without eosinophilic infiltrates. Botulinum toxin injection provided limited relief. Diagnostic laparoscopy confirmed the hypertrophic pylorus and we performed laparoscopic pyloromyotomy. The patient tolerated the procedure well and had complete symptom resolution at 1-year follow-up. Hypertrophic pyloric stenosis is a rare cause of gastric outlet obstruction in adolescents and may be managed successfully with laparoscopic pyloromyotomy.