Meckel's diverticulum presenting as massive gastrointestinal bleeding in a 2-year-old child: A case report.

Massive lower gastrointestinal bleeding in young children is a rare but potentially life-threatening emergency requiring rapid localization of the bleeding source. We report the case of a 2-year-old child who presented with abrupt onset of profuse rectal bleeding, profound anemia (hemoglobin 4.6 g/dL), and hemodynamic instability. Emergency computed tomography angiography demonstrated active intraluminal contrast extravasation within the small bowel, associated with imaging signs of hypovolemic shock. No target vessel amenable to endovascular treatment was identified, and urgent surgical exploration was performed. Resection of an ileal lesion confirmed Meckel's diverticulum with ectopic gastric mucosa as the source of bleeding. This case highlights the value of CT angiography for early diagnosis and management of massive gastrointestinal bleeding in pediatric patients.