Antibiotic resistance in the topical treatment of acne vulgaris.

Topical antimicrobial agents are the first line of treatment in mild to moderate acne vulgaris. The primary pathogenic agent implicated in the development of inflammatory acne is Propionibacterium acnes. P acnes also may play a secondary role in noninflammatory acne or comedogenesis. Over the past 20 years, concern has grown about the gradual worldwide increase in the prevalence of antibiotic-resistant P acnes strains. Factors associated with the development of resistant P acnes following treatment with topical antibiotics, clinical relevance of antibiotic resistance, and strategies to reduce the incidence of P acnes resistance are discussed in this review.