Management of the Meckel's diverticulum consists of hemodynamic stabilization followed by surgical resection. A child who experiences gastrointestinal bleeding from a Meckel's diverticulum typically presents acutely, with large volume (>30 mL) rectal bleeding that may require transfusion. The diagnostic imaging modality of choice is the nuclear medicine Technetium-99m pertechnetate scan (Meckel's scan).7 It localizes ectopic gastric mucosa that is found within the Meckel's diverticulum (Fig. 49-1) and elsewhere such as in enteric duplication cysts.2,8 A technetium-99m pertechnetate scan identifies the lesion in approximately 80% to 90% of cases.
False-positive results can occur with ureteral obstruction, inflammatory masses such as those seen in Crohn's disease, abscess, arteriovenous malformation, or intussusception. A negative scan should not delay surgical intervention if bleeding from a Meckel's diverticulum is strongly suspected. Technetium 99m-labeled red cell scan, also called a “bleeding scan,” can also help to localize a lesion that bleeds intermittently or at a low rate (0.1–0.3 mL/min or 500 mL/day) and eludes endoscopic detection. Labeled red cells remain in circulation for up to 5 days, which allows detection of intermittent bleeding. In rare cases in which Meckel's diverticulum is strongly suspected and the Meckel's scan yields negative results, abdominal computed tomography scan, angiography, and exploratory laparoscopy can be considered.9 Once confirmed, the definitive treatment is excision of the lesion.
Other possibilities for painless rectal bleeding include juvenile colonic polyps, and, less commonly, hemangiomas, venous malformations, or a brisk upper gastrointestinal bleed. The investigations for these conditions are beyond the scope of ED management.