"False-negative" Meckel's scan caused by a recent barium study

An 18-year-old girl was hospitalized because of acute gastrointestinal bleeding. A Meckel's scan (with Tc-99m pertechnetate) was falsely interpreted as negative for Meckel's diverticulum as a result of contrast material attenuation in the lower abdomen after recent enteroclysis with barium. A Tc-99m-labeled red blood cell scan obtained during a second hospitalization was positive for gastrointestinal bleeding in the ileocecal region. A missed Meckel's diverticulum was considered the cause of this bleeding, and another Meckel's scan was obtained. Surgery after this positive Meckel's scan showed a Meckel's diverticulum containing gastric mucosa. After barium is used in an evaluation of the gastrointestinal tract, a Meckel's scan should be delayed until barium has cleared from the bowel, as documented by radiographic evaluation, or until its clearance would be expected. Repeated examination can improve diagnostic accuracy when this barium pitfall is not avoided.