Isotretinoin and lymecycline treatments modify the skin microbiota in acne

Oral retinoids and tetracyclines have a major role in acne treatment. Here, we report for the first time the effect of isotretinoin and lymecycline therapy on the skin microbiota in cheek, back and armpit swab samples of acne patients using 16S rRNA gene amplicon sequencing. An OTU likely to correspond to Propionibacterium acnes was the most common in sebaceous areas of healthy and untreated acne skin and more abundant in back than cheek samples. Five taxa differed significantly between the cheek samples of healthy controls and acne patients, but not in back samples. Both treatments reduced the clinical acne grades and the abundance of Propionibacterium especially in cheek samples, while the abundances of several taxa were significantly higher in treated cheek samples compared with untreated ones. Less differences were observed in back samples and none in armpit samples. There were no differences in alpha diversity between control and acne cases in any location, but after both treatments, the microbiota in cheek and back samples were significantly more diverse than in untreated skin. The data obtained in this study provides insights into the skin microbiome in acne and its modification by systemic treatments.