Rinitis alérgica e hiperreactividad bronquial

Bronchial hyperreactivity (BHR) is a characteristic of bronchial asthma. Patients with allergic rhinitis who do not report symptoms of bronchial asthma on spirometry show BHR, which could indicate the presence of subclinical inflammation of the lower respiratory airway. The aim of this study was to investigate whether the patients diagnosed with allergic rhinitis in our unit without symptoms of bronchial asthma had bronchial hyperreactivity and to determine which allergens caused these symptoms in our patients.We performed a retrospective, observational study of patients diagnosed with allergic rhinitis in our Allergy Unit between August 2000 and December 2001. The patients' medical records were reviewed and data on the following were gathered: demographic information, age, sex, rhinitis symptoms (perennial or seasonal), conjunctivitis, atopic dermatitis, bronchitis, sensitization (specific IgE, skin tests, nasal challenge tests), total IgE levels, spirometry performed through stress test (positive with a decrease of FEV1 > 15 % with stress or an increase of FEV1 of 12 % after bronchodilation) and family history of allergic disease. A total of 135 medical records of patients with allergic rhinitis were reviewed. Of these, 68 did not report symptoms of bronchial asthma (35 men and 33 women aged between 4 and 18 years). Most of our patients (50/68) reported perennial asthma and were sensitized to mites (44/68). In 14/68 spirometry was not performed at diagnosis. Stress test was positive in 13/54 (24 %). All patients who showed bronchial hyperreactivity were sensitized to mites and only one of these reported seasonal rhinitis.According to the latest guidelines on the treatment and control of allergic rhinitis --The Allergic Rhinitis and its Impact on Asthma Workshop Report-- bronchial asthma and allergic rhinitis are distinct manifestations of a single airway and of the same disease. In view of our results, we recommend systematic evaluation of bronchial hyperreactivity in the study protocol of allergic rhinitis in patients who do not report symptoms of bronchial asthma.