Residual spleen found on denatured red blood cell scan following negative colloid scans

The technetium-sulfur colloid liver-spleen examination is widely used to evaluate patients with idiopathic thrombocytopenic purpura for residual splenic tissue following splenectomy. Technetium-labeled heat-damaged red blood cell imaging is another sensitive test for residual splenic tissue. We recently encountered a patient with idiopathic thrombocytopenic purpura who was initially evaluated with a technetium sulfur colloid scan which was negative. A denatured red blood cell scan was subsequently performed which revealed intense focal activity in the region of the splenic bed. Surgery confirmed this to be splenic tissue. Our results emphasize the utility of the denatured red blood cell examination in the setting of strong clinical suspicion for residual splenic tissue following a negative sulfur colloid study.