Multidrug-resistant Acinetobacter baumannii infection following para-articular steroid injection in the knee--a case report.

Acinetobacter baumannii is an emerging gram-negative nosocomial pathogen that rarely causes infections in orthopaedic patients. We report a case of imipenem-resistant Acinetobacter baumannii paraarticular infection of the knee occurring in a healthy patient following one ambulatory steroid injection for the treatment of quadriceps tendinopathy. The infection was reduced by early surgical debridement of infected tissues, abscess drainage, and prolonged antibiotic therapy with colistin. To our knowledge, this is the first case in the literature reporting such an infection following single steroid injection in orthopaedic patients.