Obscure Gastrointestinal Bleeding in an Adolescent Masked by Gastric Erosions: Meckel's Diverticulitis Complicated by Adhesive Obstruction and Small Bowel Perforation.

Meckel's diverticulum is the most frequent congenital anomaly of the gastrointestinal tract, yet its identification can be challenging when symptoms mimic those of more common conditions. In adolescents, this often leads to misdirection during the diagnosis and delays in identifying the true source of bleeding. A 16-year-old male presented with recurrent melena and abdominal pain. Initial esophagogastroduodenoscopy (EGD) revealed mild gastric erosions, and colonoscopy was normal, prompting treatment for gastritis and temporary symptom resolution. Ten months later, he returned with massive gastrointestinal bleeding. CT imaging suggested Meckel's diverticulitis, which was confirmed intraoperatively, and the patient underwent segmental small bowel resection with appendectomy. Histopathology confirmed Meckel's diverticulitis, which contained ectopic gastric mucosa. This case highlights the diagnostic pitfalls of obscure gastrointestinal bleeding in young patients. Mild gastric erosions should not preclude the evaluation of the small bowel when bleeding persists. Early consideration of Meckel's diverticulum can help prevent avoidable morbidity and ensure timely, effective management.