Mupirocin resistance and methicillin-resistant Staphylococcus aureus (MRSA).

Mupirocin has become the topical agent of choice for the elimination of methicillin-resistant Staphylococcus aureus (MRSA) carriage. The increased use of this antibiotic has been followed by reports of outbreaks due to MRSA with both low- and high-level resistance. Whilst low-level resistance is becoming more widespread, it is unlikely to have a major impact upon current practice. High-level resistance is plasmid borne, and although uncommon, can lead to problems with elimination especially in an outbreak situation. Alternatives are available but uncertainty exists as to their efficacy and safety. Any strategy to limit the increase of mupirocin resistance in MRSA should emphasize the importance of controlled antibiotic use both for mupirocin and other agents.