THE SPECTRUM OF MYOSITIS AND RHABDOMYOLYSIS ASSOCIATED WITH BACTERIAL-INFECTION

Objective. (1) To describe the clinical and radiographic features of 6 patients with myositis or rhabdomyolysis associated with bacterial in fection. (2) To analyze the role of computed tomography (CT) in myosit is associated with bacterial infection. Methods. Review of cases treat ed by the authors with literature review. Results. Two patients had cl assical pyomyositis with Staphylococcus aureus as the etiologic agent. One patient had pyomyositis with Enterobacter cloacae (the first repo rted to our knowledge), 2 had myositis/fasciitis (one due to Clostridi um perfringens and one due to S. aureus), and one had fatal toxic rhab domyolysis in association with C. perfringens bacteremia without evide nce of gas gangrene. No patient had a completely normal CT scan of aff ected muscles, but CT scans in 3 patients failed to show abscesses tha t were subsequently discovered at surgery, while in another patient CT scanning falsely suggested a large abscess that was not present at su rgery. Conclusion.Infection associated muscle involvement represents a spectrum of clinical manifestations that include pyomyositis, myonecr osis, fasciitis/myositis, and toxic rhabdomyolysis. Diagnosis may be d elayed by the often mild clinical presentation. CT scanning alone may be unreliable in distinguishing muscle abscess from swollen muscle unl ess combined with CT guided needle biopsy.