Abstract

Isotretinoin, a retinoid – can be used to treat patients with moderate to severe acne despite the adverse effects of mucosal surface drying and the contraindication of use during pregnancy. Commonly, patients prescribed systemic isotretinoin have previously not responded to treatment with oral or topical antibiotics. Broad-spectrum antibacterial therapy attempts have, however, promoted changes in the diversity and antibiotic resistance status of the patients’ skin microbiota. The present study involved the recovery and analysis of skin organisms from 53 patients (mean age 23 y range 15-37 y) before, during and after treatment with a 16-week course of isotretinoin. Isotretinoin has been shown to lead to profound reductions in the microflora of patients. Many bacteria had high levels of antibiotic resistance from the outset. The work has progressed with the analysis of the diversity and resistance of Propionibacterium acnes strains present originally and during recolonisation.