Epidemiologic data about polymorphous light eruption in Italy

Aim. Polymorphous light eruption (PLE) is the most common idiopathic photodermatosis. It describes a broad clinical spectrum with chronic recurrences. It is often characterized by non scarring pruritic erythematous papules, vesicles or plaques. UV exposure is the main pathogenetic factor. The aim of this study was to evaluate the prevalence of PLE in Italy, the main clinical features and the clinical course and recurrences in a Mediterranean population. Methods. The study was carried out on 4 416 subjects in 8 Dermatological Units in Italy, distributed over the whole country. Subjects were required to fill a simple questionnaire (43 questions) exploring the following topics: phototype and phenotype, and modalities of solar exposure. In the subjects with a previous PLE another questionnaire was submitted to investigate the clinical features of PLE, number of recurrences, familiar, pathological and pharmacological anamnesis. The study was carried out in healthy volunteers, not affected by any dermatological disease. Results. Among the 4 416 apparently healthy subjects who filled out the survey, 212 gave a history consistent with a diagnosis of PLE. The PLE prevalence was 5.89% without significant differences among the Dermatological Units distributed at different latitudes in our Country. The coalescent papules type of PLE was the most common clinical picture (36.4%); the body site most frequently affected was the trunk (61.1%). On the contrary, chronically sun exposed body site (i.e. the face) is affected just in few cases. Also people chronically sun exposed developed PLE less frequently than occasionally sun exposed people. Sometimes, PLE developed after a particularly intense sun exposure (37.7% of PLE). Conclusion. No correlations with drug assumption or environmental chemical compound have been underlined