Study objective: Previous studies have suggested that aggressive treatment of sinusitis can decrease bronchial hyperresponsiveness (BHR). However, there is still too little evidence to draw this conclusion, and the concept remains controversial.
Design: A prospective, open-label study.
Setting: University children's hospital allergy and immunology center and radiologic department.
Patients: Sixty-one children with mild asthma and allergic rhinitis participated in the study. Forty-one of these 61 children had sinusitis, and the remainder had no sinusitis. Ten matched, nonatopic, healthy children were used as a control group.
Intervention: Children with chronic sinusitis were placed into two groups. One group was treated with amoxicillin-clavulanate for 6 weeks and then with nasal saline solution irrigation for 6 weeks. For the other group, the treatment order was reversed. Children without chronic sinusitis received nasal saline solution irrigation for 12 weeks.
Measurements: Clinical symptoms and signs of sinusitis, FEV(1), and BHR were analyzed in the patients before and after treatment.
Results: The clinical symptoms and signs of sinusitis, but not FEV(1), showed a significant improvement after antibiotic treatment. After aggressive treatment for sinusitis, it was found that the provocative concentration of methacholine causing a 20% fall in FEV(1) of children with mild asthma and sinusitis was significantly higher after treatment.
Conclusion: The results suggest that every asthmatic patient needs to carefully evaluate to determine whether the patient has concomitant sinusitis. Respiratory infections that meet criteria for sinusitis, even if they do not exacerbate asthma, should be treated. It is suggested that sinusitis should always be kept in mind as a possible inducible factor for BHR, and that aggressive treatment of chronic sinusitis is indicated when dealing with an asthmatic patient who shows an unpredictable response to appropriate treatment. Moreover, the findings of this study provide more evidence for an association between sinusitis and asthma with respect to BHR.