1 Division of Dermatology, Department of Specialized, Experimental and Diagnostic Medicine, S. Orsola-Malpighi Hospital, University of Bologna, Bologna, Italy.
2 Department of Health Sciences, University of Florence and Department of Paediatric Medicine, Anna Meyer Children's University Hospital, Florence, Italy.
3 Department of Histopathology and Transplantation Pathology, S. Orsola-Malpighi Hospital, University of Bologna, Bologna, Italy.