Iperreattività bronchiale aspecifica in pazienti monosensibili con rinite allergica: variazioni stagionali in rapporto alle IgE sieriche totali ed agli eosinofili ematici

Introduction: The significance of the association between allergic rhinitis and abnormal airway responsiveness is unclear. For this reason, we have studied, in patients with seasonal allergic rhinitis, non specific bronchial hyperreactivity, total serum IgE and blood eosinophils, with reference to the responsible allergen, during and out of the pollen season. Materials and methods: Fourty-nine, non-smoking patients, living in Palermo, with clinical diagnosis of allergic rhinitis, skin prick tests and specific serum IgE mono-sensitive to pollen allergens, were enrolled in the study. Twenty patients suffered from seasonal rhinitis to Parietaria pollen, 15 patients to Graminacee pollen and 14 patients to Olea pollen. In all patients lung function measurements (assessed as response to methacholine), total serum IgE and blood eosinophil counts were measured, during and out of the pollen season. Results: During pollen season, 16 out of 49 rhinitis patients demonstrated values of bronchial responsiveness, measured as response to inhaled methacholine, in the asthmatic range (PC20-FEV1 ≤ 1,500 μg/mL), whereas, out of the pollen season, only 8 patients were in the asthmatic range. By analyzing the results with reference to the responsible allergen, during the pollen season, 15 out of 16 patients were Parietaria-sensitive and, out of the pollen season, 7 out of 8 patients. Finally, in Parietaria-sensitive rhinitis, bronchial responsiveness significantly correlated, during and out of the pollen season, with total serum IgE and blood eosinophil counts. Conclusions: The results of this study underline that the percentage of allergic patients to Parietaria with a PC20-FEV1 to methacholine in the asthmatic range is greater to that of allergic patients to Graminacee and Olea. Besides, our results are consistent with the hypothesis that Parietaria is more important than Graminacee and Olea as a risk factor for developing of non specific bronchial hyperresponsiveness, expecially during the pollen season.