Pediatric emergency medicine trisk 3780 3780

complication of a Meckel diverticulum is a bleeding ulcer, typically presenting as
painless rectal bleeding. Ectopic gastric mucosa in such patients is usually present
in the diverticulum. The acid secretion produces ulceration at the junction of the
normal ileal mucosa with the ectopic mucosa. Currant jelly stools or hemorrhage
may be present. Other modes of presentation include diverticulitis, perforation
with peritonitis, or intussusception with the diverticulum serving as a lead point.
Enteral contrast studies usually fail to outline a Meckel diverticulum. The
imaging modality of choice for detection of ectopic gastric mucosa in a bleeding
Meckel diverticulum is nuclear scintigraphy. A well-defined focal accumulation
of radionuclide (99m-technetium pertechnetate) usually appears at or about the
same time as activity in the stomach and gradually increases in intensity ( Fig.
116.19 ). A duplication cyst with gastric mucosa shows the same focal
accumulation of radionuclide. Preoperative differentiation between two lesions as
a cause of GI bleeding is not important. The accuracy of scintigraphy in detection
of ectopic gastric mucosa in Meckel diverticula is approximately 95%. Falsenegative results may rarely occur in patients with rapidly bleeding Meckel
diverticula and with those diverticula that do not contain gastric mucosa.
In any child with a major rectal bleed and a negative scan, further workup is
required, including an arteriogram if the bleeding continues to be active or
colonoscopy when the bleeding is not active.