Importance of dressing removal before radiolabeled WBC imaging for musculoskeletal infection.

Leukocyte imaging performed with in-111 or Tc-99m is gaining widespread acceptance as a method for detection of osteomyelitis associated with soft tissue injury or infection. The authors present three cases in which initial imaging was suggestive of a focal infectious process in bone and soft tissue. However, repeat imaging after the removal of wound dressings, which revealed sero-sanguineous discharge in all cases, resulted in a scan appearance that was much less remarkable for focal radiotracer accumulation in the bone. The authors conclude that accumulation of labeled WBCs in wound discharge can result in scans that are false-positive for osteomyelitis. Therefore, the authors recommend that wounds should be cleaned and dressings changed before imaging in order to avoid scans that are false-positive for osteomyelitis.