Pityriasis versicolor: clinical-epidemiological characterization of patients in the urban area of Buerarema-BA, Brazil

BACKGROUND: Pityriasis versicolor (PV) is a cutaneous pigmentation disorder caused by a lipophilic yeast of the genus Malassezia sp. It is a superficial mycosis characterized by well-defined, slightly scaly skin lesions of variable color. In Brazil, the number of reported cases is small, and there are few epidemiological studies. OBJECTIVES: to assess incidence, characteristics of the lesions, effectiveness of the Zileri's Sign procedure, and the epidemiological profile of PV in the urban area of Buerarema - Bahia. METHODS: Biological samples were collected on pre-established days at Basic Health Care Units from July to September 2010. Sample collection was followed by laboratory diagnosis using Porto's Method. RESULTS: Of the 158 patients with suspected PV participating in the study, 105 (66.5%) were positive; 72 (68.6%) were female and 33 (31.4%) were male. Sex and location of lesions showed statistically significant differences (p<0.05). The region with the highest rate of cases of PV was found to be the center of the city, with 40.9% of diagnosed cases. The most affected age group was between 10 and 19 years. There was a significant association between the results produced through Zileri's Sign and Porto's Method in relation to positive and negative results (p<0.05). CONCLUSIONS: The results showed a higher prevalence of PV among individuals at puberty. The Zileri's Sign method proved to be counterproductive, because it showed low efficacy as a method for clinical diagnosis, yielding negative results for 36 (34.3%) patients who had been diagnosed with PV through laboratory examination.