Adrenal mass and renal vessels mimicking intestinal bleeding on Tc-99m red blood cell scintigraphy

Technetium-labeled erythrocyte scintigraphy in acute gastrointestinal bleeding

PURPOSE

Optimal management of acute gastrointestinal (GI) bleeding requires accurate localization of the bleeding source. The role of technetium-labeled erythrocyte scintigraphy (tagged red blood cell (TRBC) scan) in evaluating acute GI bleeding has been controversial, though recent literature suggests that it is a reliable tool and may be used as a first-line diagnostic test. We evaluated our recent experience with and the clinical outcomes of the TRBC scan in patients presenting with acute GI bleeding.

METHODS

A retrospective study of 100 consecutive TRBC scans performed between April 2006 and January 2009 was conducted. Medical records of each corresponding patient were queried for pertinent data. Twenty TRBC scans performed for occult GI bleeding or >48 h after hospital admission were excluded.

RESULTS

Of the 80 TRBC scans, 29 (36%) were positive and 51 (64%) were negative for bleeding. Eight (10%) were incorrect positive (leading to five incorrect operations), 12 (15%) true positive, 9 (11%) unconfirmed positive, 17 (21%) false negative, and 34 (43%) unconfirmed negative. The cause of bleeding was confirmed in 31 cases, of which the scan result was incorrect positive in 2 (7%), true positive in 12 (39%), and false negative in 17 (55%).

CONCLUSIONS

TRBC scans have low positive yield as well as high incorrect positive and high false negative rates in patients with acute GI bleeding. Further research is needed to improve scan technique, refine patient selection, and determine in what setting TRBC scanning may be more clinically useful.