pH and Acne.

Acne is based on a complex, multifactorial pathophysiology beginning with a microcomedo. Comedogenesis involves follicular hyperproliferation and disturbed keratinization, hyperseborrhea and hyperplasia of sebaceous glands as well as disturbances in skin microbiome. Acne is treated with antibiotics, retinoids, keratolytics, hormonal and anti-inflammatory agents. Efficacy and side effects of given medications are well known. The uppermost layer of the stratum corneum is acidic. The low pH provides protection by slowing down the growth of some bacteria. Increase of skin surface pH leads to impaired barrier function, disturbances in skin microbiome and inflammation. Acne-predisposed skin is in a constant state of subclinical inflammation. Subclinical inflammation may be linked to changes in skin surface pH and disturbances of the stratum corneum, allowing microorganisms to stimulate the production of pro-inflammatory cytokines. Here, based on the current literature, the possible link between the skin surface pH, epidermal barrier function and acne is reviewed.