Clinical and erythema-directed imaging evaluation of papulo-pustular rosacea with topical ivermectin: a 32 weeks duration study.

Background: Ivermectin (IVM) 1% cream represents an emerging therapy for papulo-pustular rosacea (PPR) and erythema-directed photography is a useful tool for evaluation of patient's erythema. Objective: The aim of our study was to assess the efficacy of IVM in PPR in achieving clear status at 8 weeks or at 20 weeks followed by respectively 24 and 12 weeks follow-up, using clinical/instrumental evaluation. Methods: Twenty patients with PPR were instructed to apply IVM for 8 weeks. At week 8, in case of complete response the therapy was stopped and a follow-up period up to 24 weeks was carried out, whereas in case of improvement the treatment was extended for additional 12 weeks followed by a 12 weeks follow-up. Instrumental evaluation was performed by erythema-directed digital photography (VISIA-CRTM- RBXTM). Results: At week 8, complete response was observed in 31.6% of cases along with a significant decrease of erythema degree. During treatment extension, additional improvement in terms of complete response, respectively at 12 (42%), 16 (47%) and 20 (58%) weeks, and reduction of erythema degree was observed. Conclusions: IVM is a valuable therapeutic option in mild/moderate PPR. Erythema-directed digital photography enhances erythema changes visualization compared to clinical observation alone.