Acoustic Rhinometry and Aspirin Nasal Challenge in the Diagnosis of Aspirin-Intolerant Asthma: Clinical Finding and Safety Aspects

Background: The safety and utility of nasal provocation tests with lysine-aspirin (l-ASA) in the diagnosis of aspirin-intolerant asthma (AIA) have previously been described in a short series of patients. Objectives: To describe the clinical features and safety of an l-ASA challenge test in patients with AIA. Methods: We evaluated 72 patients (79% women), with a mean ± SD age of 47.9 ± 14.5 years. All patients were submitted to an l-ASA nasal provocation test (29 mg in each nostril) under acoustic rhinometry (AcR) control. Symptom score (0–3), visual analogical scale and nitric oxide determinations were performed at baseline and at 15, 30, 60 and 90 min. A decrease in nasal volume of at least 25% was considered a positive test. Nasal nitric oxide (nNO) and forced expiratory volume in 1 s were measured. Results: Nasal congestion and rhinorrhea represented 51 and 32%, respectively, of total symptoms. According to AcR data, the l-ASA challenge test was positive in 20% of patients at 15 min, an additional 36% were positive at 30 min, 18% at 60 min, and the remaining 26% at 90 min. nNO nasal values decreased but did not reach statistical significance. No pulmonary or systemic reactions were observed. Conclusions: Symptoms of nasal congestion associated with the reduction in nasal volume measured by AcR are the most useful parameters for establishing the diagnosis of AIA using the l-ASA nasal challenge. The method is very well tolerated and can be safely used even in patients with severe asthma.