1. Pediatric Dermatology Division; Hospital General de Agudos, JM Ramos Mejía; Buenos Aires; Argentina
2. Section of Dermatology; Fondazione IRCCS Cà Granda-Ospedale Maggiore Policlinico di Milano, Department of Pathophysiology and Transplantation, University of Milan; Milan; Italy
3. Department of Dermatology; Ospedali Riuniti di Bergamo; Bergamo; Italy
4. Section of Dermatology; DISSAL and Institute of Pathology, University of Genoa; Genoa; Italy