BACKGROUND: Allergic rhinitis (AR) is a global health problem and is characterised by one or more symptoms, including sneezing, itching, nasal congestion and rhinorrhea. OBJECTIVE: We investigated the features of AR and the physician's approach to the management of AR patients in four geographical regions. METHODS: In this cross-sectional study, a questionnaire survey concerning AR was completed by Honorary and Corresponding Members of the Italian Society of Rhinology from different countries among 4 world geographical regions—Asia, Europe, the Americas, and Africa. RESULTS: The prevalence of AR was reported to be 15%–25%. Children and adolescents, as well as young adults, were the age groups more affected by AR with comorbidities of asthma, sinusitis, conjunctivitis, and nasal polyposis. Nasal symptoms of AR were more intense in the spring (51.92%) and autumn (28.85%). The most common aero-allergens were pollen and mites (67.31%), animal dander and pollutants (23.08%), and fungal allergens (21.15%). Allergen-specific immunotherapy was prescribed for both perennial and seasonal allergens (32.69%) via sublingual swallow (46.15%) and subcutaneous (32.69%) routes. For the AR patients, the most prescribed drugs were intranasal corticosteroids (86.54%) and oral H₁-antihistamines (82.69%). CONCLUSION: A network of experts can improve our knowledge concerning AR epidemiology, and together with guidelines, could assist practitioners and otolaryngologists in standardising the diagnosis and treatment of AR.
Adolescent ; Adrenal Cortex Hormones ; Africa ; Allergens ; Americas ; Animals ; Asthma ; Child ; Comorbidity ; Conjunctivitis ; Cross-Sectional Studies ; Dander ; Diagnosis ; Epidemiology ; Estrogens, Conjugated (USP) ; Europe ; Global Health ; Humans ; Immunotherapy ; Mites ; Pollen ; Prevalence ; Pruritus ; Rhinitis, Allergic ; Seasons ; Sinusitis ; Sneezing ; Sublingual Immunotherapy ; Young Adult

OBJECTIVES: The aim of this study is to investigate the role of platelet-derived growth factor (PDGF) in the pathogenesis of sinonasal polyps. METHODS: Study group (groups 1-3) consisted of nasal polyp samples of patients with sinonasal polyps and the control group consisted of inferior turbinate samples of patients without nasal polyp. In group 1, 14 specimens from ethmoid sinus; in group 2, 10 specimens from nasal cavity; in group 3, 10 specimens from maxillary sinus; and in group 4 (control), 9 specimens from inferior turbinate were included. By immunohistochemical staining technique, the PDGF positivity index (PI) in mucosal layers and in the inflammatory cells were assessed at the epithelium (EP), subepithelial layer of lamina propria (SE), and deep paraglandular layer of the mucosa (D). RESULTS: Polymorphonuclear cell (PMNC)-percentage (%) values of ethmoid and maxillary sinus, and the PDGF PI from all cells of ethmoid sinus and nasal cavity were significantly higher than those of the control group. As mononuclear cell-% (MNC-%) increased, the PDGF_EP_basal PI, PDGF_SE_endothelial PI, and PDGF_D_endothelial PI decreased. As PMNC-PDGF PI increased, the PDGF_D_perivascular PI decreased and PDGF_D_endothelial PI increased. As PDGF-MNC PI increased, the PDGF_EP_apical PI, PDGF_SE_endothelial PI, and PDGF_D_endothelial PI decreased. As PDGF-all cells (PMNCs, MNCs, and fibroblasts) PI increased, the PDGF_EP_basal PI and PDGF_D_endothelial PI decreased, and the PDGF_D_perivascular PI increased. CONCLUSION: We concluded that the PDGF systems play important roles in polyp pathogenesis. Fibroblast-derived PDGF may be more important than MNC-derived PDGF in polyp developing process. Increased perivascular-PDGF-PI in deep layers of the mucosa may result in sinonasal polyp formation by causing an increase in vascular permeability and extracellular edema, and thus promoting migration of inflammatory cells to extracellular area. Tissue oxygenization may be important for the initiation of PDGF release system. Because of this reason, nasal obstruction should be medically treated earlier, and, if necessary, by surgical approaches.
Capillary Permeability ; Edema ; Epithelium ; Ethmoid Sinus ; Humans ; Maxillary Sinus ; Mucous Membrane ; Nasal Cavity ; Nasal Obstruction ; Nasal Polyps ; Oxygen ; Platelet-Derived Growth Factor ; Polyps ; Turbinates