Technetium-99m-nanocolloid scintigraphy in orthopedic infections: a comparison with indium-111-labeled leukocytes

Twenty-three patients with clinically suspected acute or chronic osteomyelitis and 21 patients with suspected joint prosthetic infection underwent scintigraphy using both 99mTc-nanocolloid and 111In-labeled leukocytes. The scintigrams of the two tracers were blindly interpreted by three independent observers. Their evaluations showed high correspondence. Patients were classified as having no infection, probable infection or proven infection according to specific criteria which included results of bacteriological cultures and histopathological examinations. For proven and probable infection taken together, the sensitivity with 99mTc-nanocolloid was 94%, the specificity 84% and the accuracy 87%, compared with 75%, 90% and 85% with 111In-labeled leukocytes. We conclude that 99mTc-nanocolloid scintigraphy is at least equivalent with 111In-leucocyte scintigraphy, and its additional advantages are shorter examination time, less complexity and better radiation dosimetry.