How should nasal symptoms be investigated in asthma? A comparison of radiologic and endoscopic findings.

Background: To improve asthma control, the management of rhinosinusitis often leads the physician to perform sinonasal imaging and/or nasal endoscopy, but their respective contributions are still insufficiently understood.

Objective: To evaluate the potential contribution of a symptoms questionnaire, sinus radiography (SR) and computed tomography (CT) scan to the diagnosis of nasal diseases in asthmatic patients when compared with ENT examination.

Methods: A total of 124 patients completed a questionnaire on nasal symptoms administered by the chest physician. Then, they underwent ENT examination. On the same day, SR and CT scans were performed independently.

Results: Patients (80.3%) had nasal symptoms during the month preceding the consultation. The ENT examination was normal in 8.1% (n = 10) and revealed rhinitis in 57.3% (n = 71), rhinosinusitis in 14.5% (n = 18) and nasal polyposis in 20.2% (n = 25). For rhinitis, the negative predictive value of bilateral nasal obstruction was 87.8%. Both SR and CT had low sensitivity and specificity. For rhinosinusitis, the negative predictive value of nasal symptoms varied from 85.4 to 95.2%. Sinus CT was at least as accurate as SR for the diagnosis of rhinosinusitis. In a multivariate analysis, only the CT scan (score > or =12) appeared to be significantly associated with the diagnosis of nasal polyposis.

Conclusion: In asthmatic patients, physicians need to enquire systematically about the existence of nasal symptoms by using this simple questionnaire which is sensitive for rhinitis, and has good negative predictive value for excluding rhinosinusitis and nasal polyposis.