Small airway impairment and bronchial hyperreactivity in patients with house dust mites-allergic rhinitis.

Background: Patients with allergic rhinitis (AR) and bronchial hyperreactivity (BHR) may be at higher risk of developing asthma.

Objective: The study was to investigate whether reactivity to house dust mites (HDM) and serum IgE level can be used to predict BHR.

Methods: A total of 75 asthmatic patients were included in the study. All patients performed spirometry and underwent a bronchial challenge with histamine.

Results: Seventy-five patients with HDM-positive skin prick tests who underwent airway provocation tests were included in this study. Small airway dysfunction was found in 19 patients. After the histamine challenge, the change of forced expiratory volume in the first second (FEV1) was more than 15% in 48 patients and more than 20% in 42 patients. There were positive associations between serum IgE levels and FEV1 fall value. The following cutoff values showed the best combination of sensitivity and specificity for AR with BHR: Serum total IgE 104.2 IU/mL (area under the curve [AUC]: 0.711, P = 0.0019), Dermatophagoides pteronyssinus-specific IgE 13.7 IU/mL (AUC: 0.799, P < 0.0001), Dermatophagoides farinae-specific IgE 27.8 IU/mL (AUC: 0.743, P = 0.0009).

Conclusion: AR patients with HDM allergy have small airway dysfunction and airway hyperresponsiveness, and airway hyperresponsiveness is related to the degree of allergy. Simple measurement of allergen-specific IgE may be the best predictor of HDM-induced asthma in patients with AR.