Role of red blood cell scintigraphy for determining the localization of gastrointestinal bleeding

We aimed to evaluate the role of Tc-99m labeled red blood cell (RBC) scintigraphy for determination of localization of gastrointestinal system (GIS) bleeding.

Fifty-seven cases (27 females, 30 males; mean age 43.9±24; range 1 to 91 years) who referred to our clinic between 1995-2010 were evaluated for determination of localization of GIS bleeding with RBC scintigraphy. Prior to scintigraphy, gastroscopy in 51, colonoscopy in 45, and angiography in 9 patients were performed.

RBC scintigraphies were positive and negative in 31 and 26 patients, respectively. Positive scintigraphic findings were obtained within the 1st hour of dynamic imaging in 19 patients, within the 1st-4th hour static images in 7, and within the 4th-24th hour images in 5 patients. Fourteen patients underwent surgical exploration. In 13 patients, the surgery confirmed the diagnosis by RBC scintigraphy (accuracy: 92.8%). Of 43 patients without surgical exploration, 12 had anemia due to iron deficiency and their scintigraphic evaluation were negative. Four patients died and in 27 patients, GIS bleeding ceased spontaneously or with conservative measures.

Scintigraphy should be the primary tool for accurate diagnosis of patients with active GIS bleeding. Positive dynamic images obtained within the first hour of imaging may be more accurate for demonstrating bleeding localization and a good predictor of requirement of surgical exploration.