Successful oral pristinamycin therapy for osteoarticular infections due to methicillin-resistant Staphylococcus aureus (MRSA) and other Staphylococcus spp

OBJECTIVES: Oral treatment regimens for multiresistant methicillin-resistant Staphylococcus aureus (MRSA) infections are limited. In Australia, rifampicin plus fusidic acid is the usual treatment regimen following glycopeptide therapy but many patients are intolerant of this; some isolates are resistant; new oxazolidinones are expensive for routine use. Pristinamycin is a possible alternative and we report our experience with this agent. METHODS: The Department of Microbiology and Infectious Diseases, South Western Area Pathology Service treats patients drawn from the South Western Sydney Area Health Service that houses approximately 800,000 people and contains approximately 2000 acute care public hospital beds. Patients prescribed pristinamycin between 1 September 2000 and 31 January 2000 were identified from hospital pharmacy records. A retrospective chart review was performed. Accepted clinical definitions of osteomyelitis and septic arthritis were used. RESULTS: Twenty-seven patients were identified with osteoarticular infections. Twenty-four cases involved Staphylococcus aureus (multiresistant MRSA in 21 cases); three involved Staphylococcus epidermidis sensu stricto; four cases involved multiple organisms. Nineteen cases received pristinamycin monotherapy; the others received various combinations (fusidic acid with five; other antibiotics with three). Therapy was generally well tolerated; no haematological or biochemical toxicity was detected. Seven patients had minor gastrointestinal disturbance; and one developed rash. Four patients required dose reduction. Only four patients ceased pristinamycin due to intolerance. Treatment outcome was evaluated in 23 cases; cure was effected in 16 cases, five were successfully suppressed and two failed. There were no deaths. CONCLUSIONS: Oral pristinamycin is well tolerated and an important additional agent to treat osteoarticular infections with multiresistant MRSA and other staphylococci.