TC-99M-LABELED RED-BLOOD-CELL SCINTIGRAPHY FOR LOCALIZATION OF GASTROINTESTINAL-BLEEDING IN CHRONIC-RENAL-FAILURE

Angiodysplasia (AD) may be the source of bleeding in patients with gas trointestinal hemorrhage, with special occurrence in the elderly popul ation and in patients with chronic renal failure (CRF). Although sever al techniques have been tested for its diagnosis, the gold standard is not well defined yet. We analyze the usefulness of Tc-99m-labelled re d blood cell (Tc-99m RBC) scintigraphy in the localization of bleeding from AD lesions in a cohort of 21 patients. Other investigative metho ds include fibrocolonoscopy examination, angiography, or diagnostic la parotomy. Group A (AD and CRF): 11 patients. Group B (AD without CRF): 10 patients. Tc-99m RBC scintigraphy showed 88.9% sensitivity and spe cificity in group A, while in group B it had 100% sensitivity and spec ificity. Arteriography showed 100% sensitivity and specificity. On the contrary, fibrocolonoscopy had a very low sensitivity (30%). Our resu lts suggest that Tc-99m RBC scintigraphy may be the preferred diagnost ic tool for AD, especially in patients with CRF, in whom arteriography may accelerate the decline of renal function.