1. Unit of Pediatrics and Pediatric Emergency, University-Hospital “Policlinico-Vittorio Emanuele,” University of Catania, Catania, Italy
2. Section of Pediatrics and Child Neuropsychiatry, Department of Clinical and Experimental Medicine, University of Catania, Catania, Italy
3. Department of Pediatrics, University of Perugia, Perugia, Italy
4. Department of Biomedical and Biotechnological Sciences, University of Catania, Catania, Italy