The Usefulness of Oral Rifampin as Switch Therapy for the Soft Tissue and Bone Infections Caused by Methicillin-Resistant Staphylococcus aureus

ABSTRACT

BACKGROUND: Rifampin is sometimes used in combination with other anti-staphylococcal agents to treat methicillin-resistant Staphylococcus aureus (MRSA) infections but few reports are available about the usefulness of rifampin against MRSA infections, especially in soft tissue and bone infections. Thus, we evaluated the efficacy of rifampin as switch therapy for soft tissue and bone infections caused by MRSA and assessed the risk factors for treatment failure. MATERIALS AND METHODS: We retrospectively studied 44 patients who had soft tissue and bone infections caused by MRSA and were treated with rifampin in combination or as monotherapy as switch therapy from January 2001 to September 2004. RESULTS: The mean age of the subjects was 50.2 years and the number of male and female were 34 and 10, respectively. Median duration of rifampin use was 32 days and 25% of the patients had artificial prostheses. Thirty one patients (79.5%, 31/39) were cured with parenteral glycopeptide followed by rifampin in combination or as monotherapy. Eight patients (8/39) recurred after the completion of treatment. The presence of hip prosthesis was the only significant risk factor (P= 0.027) in multivariate logistic regression test. Rifampin was tolerable in all cases. CONCLUSION: Rifampin as switch therapy for soft tissue and bone infection caused by MRSA was effective in 79.5% (31/39) of sujects. The treatment failure seems to be associated with unremovable infected prosthesis.