Topical 5-aminolevulinic acid photodynamic therapy in the treatment of verruca plana: Report of 6 cases.

Verruca plana, also known as flat wart, is a common viral skin infection by human papillomavirus types 3, 10, 28 and 41. It's mostly prevalent on the facial area of children and young adults, becoming a heavy cosmetic burden on these patients. In this study, we report 6 cases of verruca plana predominantly affecting the visage, which are treated with 10% 5-aminolevulinic acid-based photodynamic therapy (ALA-PDT). In general, all 6 patients showed complete clearance of lesions 1 month after treatment. And clearance of lesions sustained in 4 out of 6 patients for at least 12 months after treatment. The results of this study suggest that ALA-PDT could be an effective treatment modality for verruca plana, especially for cases recalcitrant to other treatments. Nevertheless, more measures should be taken to prevent PDT-related adverse events.