1. Department of Paediatrics, University Medical Centre Maribor, Ljubljanska ulica 5, 2000 Maribor, Slovenia
2. Faculty of Medicine, University of Maribor, Taborska ulica 8, 2000 Maribor, Slovenia
3. Pediatric Outpatient Clinic, Maistrova ulica 22, 2230 Lenart v Slovenskih Goricah, Slovenia
4. Pediatric Allergy Outpatient Clinic, Lavričeva ulica 1, 2000 Maribor, Slovenia
5. Laboratory for Clinical Immunology and Molecular Genetics, University Clinic of Respiratory and Allergic Diseases Golnik, 4204 Golnik, Slovenia