An unusual white blood cell scan in a child with inflammatory bowel disease: a case report.

Technetium-99m-labeled leukocyte (WBC) imaging is a valuable screening method for inflammatory bowel disease, especially in children, because of its high rate of sensitivity, low cost, and ease of preparation. A 14-year-old girl is described who had juvenile arthritis and iritis complicated by inflammatory bowel disease. She was examined for recurrent abdominal pain. A Tc-99m stannous colloid WBC scan was performed, and tracer accumulation was seen in the small bowel in the region of the distal ileum on the initial 1-hour image. Delayed imaging at 3 hours also revealed tracer accumulation in the cecum and ascending colon, which was not seen on the early image. A biopsy of the colon during endoscopy showed no evidence of active inflammation in the colon. The small bowel was not seen. Computed tomography revealed changes suggestive of inflammatory bowel disease in the distal ileum. The appearance on the WBC study was most likely a result of inflammatory bowel disease involving the distal ileum, with transit of luminal activity into the large bowel.