Feasibility of Reflectance Confocal Microscopy Monitoring in Oily, Acne-Prone Facial Skin Treated with a Topical Combination of Alpha and Beta-Hydroxy Acids, Anti-Inflammatory Molecules, and Herculane Thermal Water: A Blinded, One-Month Study.

Oily, acne-prone skin is a common skin type which may be monitored in vivo using reflectance confocal microscopy (RCM). The aim of the study was to assess the feasibility of RCM in evaluating the effectiveness of a topical combination of alpha- and beta-hydroxy acids, anti-inflammatory and antibacterial molecules, and Herculane thermal water on acne-prone skin. Thirty-five subjects with oily, acne-prone skin were prescribed topical combination products and were evaluated by clinical, Wood's lamp, and RCM imaging at baseline and after 28 days. At 28 days, the RCM-evaluated number of dilated infundibula, infundibula filled with keratotic material, and infundibula with thickened bright borders, as well as the density of the inflammatory infiltrate, were significantly decreased. Wood's light images at 28 days showed a significantly reduced number of C. acnes -colonized infundibula, and both the median area and the intensity of the red-orange fluorescence were decreased. The reduction in the clinical score was concurrent with the improvement in the RCM parameters, suggesting that this non-invasive imaging technique is appropriate for efficiency evaluations of topical acne treatments.