1 Section of Dermatology, Department of Medical, Surgical and Neurological Science, S. Maria alle Scotte Hospital, University of Siena, Siena, Italy.
2 Section of Dermatology, Department of Medical, Surgical and Neurological Science, S. Maria alle Scotte Hospital, University of Siena, Siena, Italy - lucaprovvidenziale@gmail.com.
3 Department of Dermatology, University Hospital of St-Etienne, St-Etienne, France.