A case of cap polyposis investigated by scintigraphy with human serum albumin labeled with Tc-99m DTPA.

Cap polyposis is a rare intestinal disease that can be difficult to differentiate from inflammatory bowel disease. When cap polyposis is suspected, it is important to confirm protein loss. A 54-year-old woman who had been treated for ulcerative colitis for 7 years had severe hypoproteinemia. Scintigraphy with Tc-99m-labeled DTPA complexed with human serum albumin showed protein loss from the descending colon. Left hemicolectomy and sigmoid colectomy were performed. Cap polyposis was diagnosed on the basis of histologic findings from an operative specimen. The patient's diarrhea resolved after surgery and her hypoproteinemia improved. Scintigraphy with this label gave information helpful in the diagnosis of cap polyposis.