Rossana Schianchi1, Michela Brena2, Stefano Veraldi2. 1. Dermatological Center in Milan (C.D.M.), Milan, Italy. 2. Department of Pathophysiology and Transplantation, Università degli Studi di Milano, I.R.C.C.S. Foundation, Cà Granda Ospedale Maggiore Policlinico, Milan, Italy.