1 Allergy Center, Department of Pediatrics, Istituto Giannina Gaslini, Genoa, Italy.
2 Health Science Department, University of Genoa, Genoa, Italy.
3 Allergy Clinic, Department of Outpatients, Casa di Cura Villa Montallegro, Via Montezovetto 27, 16132 Genoa, Italy. Electronic address: gio.cip@libero.it.