Osteomyelitis and infarction in sickle cell hemoglobinopathies: differentiation by combined technetium and gallium scintigraphy.

Clinical records and scintigrams were reviewed of 18 patients with sickle cell hemoglobinopathies who had undergone combined technetium and gallium scintigraphy during 22 separate episodes of suspected osseous infection. The combined scintigrams were correctly interpreted as indicating osteomyelitis in four studies. Ga-67 localization was abnormally increased in all of these studies, including one where the Tc-99m MDP bone scan showed decreased activity, another where the bone scan was normal at the site of Ga-67 uptake, and two where the distribution of Tc-99m MDP and Ga-67 were incongruent. Of 18 studies in patients with infarction, the combined scintigrams were correctly interpreted in 16 and showed either no local accumulation of Ga-67 or less accumulation than that of Tc-99m MDP at symptomatic sites. In the other two studies, the scintigrams were falsely interpreted as indicating osteomyelitis and showed congruent, increased accumulation of both Tc-99m MDP and Ga-67 (with the latter of similar or greater intensity). This pattern must be considered indeterminate. Overall, the results indicate that the combination of technetium and gallium scintigraphy is an effective means to distinguish osteomyelitis from infarction in patients with sickle cell hemoglobinopathies.