1. Department of Internal Medicine University of Pavia and Department of the Mother and Child Health, Pediatric Unit, IRCCS Policlinico San Matteo Foundation, Pavia, Italy.
2. Biometry & Clinical Epidemiology, Scientific Direction, IRCCS Policlinico San Matteo Foundation, Pavia, Italy.
3. First Department of Medicine, IRCCS Policlinico San Matteo Foundation, Pavia, Italy.
4. Laboratory of Clinical Chemistry, IRCCS Policlinico San Matteo Foundation, Pavia, Italy.
5. Pediatric and Infectious Disease Unit, Department of Pediatrics, Bambino Gesù Children's Hospital, Rome, Italy.
6. Department of Internal Medicine University of Pavia and Department of the Mother and Child Health, Auxologic Unit, IRCCS Policlinico San Matteo Foundation, Pavia, Italy.