New aspects in the clinical course of pityriasis versicolor.

BACKGROUND Pytiriasis versicolor is an infectious disease caused by several Malassezia species which has a tendency to become relapsing or chronic. OBJECTIVES This study was conducted in an attempt to investigate the clinical course of pityriasis versicolor with regard to the number of relapses after a 12-month therapy and correlate this number with isolates of Malassezia species. MATERIAL AND METHODS 102 patients with clinical and laboratory diagnosis of pityriasis versicolor were monitored for 12 months to investigate the number of relapsing episodes of the disease. RESULTS After appropriate treatment, pityriasis versicolor presented three types of clinical course: pityriasis versicolor without relapsing episodes (32.35%), relapsing pityriasis versicolor with one to four relapsing episodes (52.94% ) due to associated predisposing factors, and chronic pityriasis versicolor with more than four relapsing episodes (14.70%) with no relation to predisposing factors. CONCLUSIONS The clinical course of pityriasis versicolor varied according to the number of relapsing episodes of the disease analyzed over a period of 12 months and can be classified as follows: pityriasis versicolor with clinical and mycological clearing, relapsing pityriasis versicolor and chronic pityriasis versicolor.