TECHNETIUM-LABELED RED-BLOOD-CELL SCINTIGRAPHY - IS IT USEFUL IN ACUTE LOWER GASTROINTESTINAL-BLEEDING

Radionuclide scintigraphy is commonly utilized as a screening examinat ion before performing more invasive procedures in the work-up of patie nts with lower gastrointestinal (GI) bleeding. We reviewed our institu tional experience with technetium-labelled red blood cell scintigraphy (TRCS) in detecting and localising acute lower GI bleeding. The study group included 72 patients who had 80 red cell scans over a five year period. Thirty-eight scans were positive (47.5%), and 42 were negativ e (52.5%). Sites of lower GI bleeding were confirmed by endoscopy, art eriography, surgery and/or pathology in 22 of the 38 positive scans. T here were four false-negative scans (9.5%). The overall sensitivity an d specificity of TRCS in detecting lower GI bleeding was 84.6% (22/26) and 70.4% (38/54), respectively. The accuracy of localization of blee ding sites in the patients with confirmed positive scans was 72.7% (16 /22). Thirty mesenteric arteriograms were performed on patients in thi s series. Eleven arteriograms were performed after negative TRCS; one was positive. Technetium-labelled red blood cell scintigraphy appears to be a useful screening examination for patients with lower GI bleedi ng who are hemodynamically stable. This may avoid the potential morbid ity of arteriography in patients who are not actively bleeding.