Evolution of skin microbiome during puberty in individuals with acne

The exact role of the skin microbiome in the development of acne is still unknown, but in addition to the well-known Cutibacterium spp., large populations of Staphylococcus spp. and Malassezia spp. are positively correlated with inflammatory acne. When microbial shifts occur during puberty or in relation to acne onset are still obscure. We performed a cross-sectional study with shotgun sequencing to identify the skin’s surface microbiome as related to pubertal development, sebum output and presence of acne. Forty-eight individuals, males and females, ages 7-17, with or without acne were enrolled. Subjects with acne had their acne graded by a dermatologist using an IGA scale. The pubertal stage of all subjects was documented according to Tanner staging criteria. Both sebum output and collection of the skin microbiome were done on the forehead. Age, race, ethnicity, use of medications, and use of makeup or lotion on the forehead at the time of sampling was documented for each individual. Increased sebum output positively correlated with pubertal development (rs = 0.901) in normal individuals, yet was not correlated in acne individuals. Globally, the skin microbiome was composed of 320 species comprising ∼80% bacteria, ∼15% virus and ∼5% fungus in this young population. As expected, the relative abundance of C. acnes significantly increased with pubertal development, regardless of acne status (p < 0.05); however, C. acnes levels were not correlated with sebum output. Interestingly, individuals with acne in early puberty (Tanner Stage 1) had 3-fold more C. acnes and 20-fold more Malassezia compared with normal individuals at the same stage (p <0.01). In contrast, the relative abundance of Malassezia significantly decreased (p < 0.01) and was negatively correlated with pubertal development (rs = -0.53; p < 0.01). Understanding the microbiome composition as it changes throughout puberty in relation to the development of acne may identify novel targeted therapeutic interventions.