ABNORMAL UPTAKE OF TC-99M HIG IN HEMATOMAS

A Tc-99m human immunoglobulin (HIG) scan was performed In a 37-year-ol d woman who was suspected of having osteomyelitis at the site of a rig ht knee prosthesis. Early and delayed images were suggestive of synovi al reaction to prosthesis material. Multiple superficial spots mimicki ng urinary contamination were visible on both upper legs, They corresp onded with sites of hematomas caused by intramuscular injection of an analgesic 3-6 days before administration of Tc-99m HIG. Laboratory eva luation revealed no coagulation disorder, and the hematomas disappeare d within 2 weeks without clinical evidence of inflammation. The author s conclude that Tc-99m HIG can show increased uptake in pre-existing h ematomas without clinical evidence of inflammation.