Unusual scintigraphic presentation of a shifting Meckel's diverticulum.

A Tc-99m red blood cell (RBC) study in a child with acute gastrointestinal bleeding of unknown origin suggested Meckel's diverticulum because of free pertechnetate uptake in the ectopic gastric mucosa. This finding has not been reported in the literature. A scan with Tc-99m pertechnetate then demonstrated a focal area of uptake with an unusual pattern of abdominal shifting consistent with a Meckel's diverticulum. A large Meckel's diverticulum containing gastric mucosa was found at surgery. A shifting pattern of focal uptake on a meckelogram study should be included among the diagnostic criteria for Meckel's diverticulum.