Propionibacterium acnes resistance: a worldwide problem.

Antibiotic therapy directed against Propionibacterium acnes has been a mainstay of treatment for more than 40 years. Despite years of widespread use of systemic tetracyclines and erythromycin, change in P. acnes sensitivity to antibiotics was not seen until the early 1980s. The first clinically relevant changes in P. acnes antibiotic sensitivity were found in the USA shortly after the introduction of topical formulations of erythromycin and clindamycin. By the late 1980s, P. acnes strains with very high MIC levels for erythromycin and elevated MICs for tetracycline were increasingly found in the UK and the USA. Mutations in the genes encoding the 23S and 16S subunits of ribosomal RNA were first identified in the UK and also seen in a recent survey from clinics in Europe, Japan, Australia and the USA. In addition, strains were found in which these known mutations could not be identified, indicating that as yet unidentified resistance mechanisms have evolved. These findings indicate the need to develop strategies to minimize the use of antibiotics in acne therapy.