Ambulante, inhalative Bronchoprovokation mit L-Acetylsalicylsäure: diagnostischer Test bei Verdacht auf Aspirin/NSAID-Intoleranz

Background: Approximately 20% of subjects with asthma experience an acute bronchoobstruction after ingestion of ASA/NSAID. In specialized clinics the inhalative broncho-provocation test (IPT) with L-ASA is a well-established method to confirm the diagnosis of aspirin-induced asthma (AIA). The objective of this investigation was to establish a new, short-during IPT with L-ASA as a diagnostic tool in an outpatient clinic. Method: In the years 2001 to 2005, 65 patients (35 F, 30 M, mean age 42 years (16 - 73 years), performed an IPT with L-ASS. Group 1 comprised 37 patients with asthma and nasal polyposis, Group 2 17 patients with asthma but without nasal polyposis, and Group 3 11 patients with only cutaneous symptoms after intake of aspirin/NSAID. The IPT was performed stepwise with 5, 15 and 40 mg L-ASA up to a cumulative dose of 60 mg. Patients with a negative IPT underwent an oral provocation test with aspirin. Results: In group 1 11/37 (30%), in group 2 6/17 (35%), and in group 3 none of 11 (0%) had a positive IPT. The threshold dose was in 13 out of 17 reactors (76%) ≤ 20 mg L-ASA. Except in 1 patient, the bronchial-obstructive reaction was well-reversible after the inhalation ofsalbutamol. 24 out of 48 patients with a negative IPT with L-ASA underwent consecutively an oral provocation test with aspirin. 4 of them reacted with mild clinical symptoms after a cumulative dose of> 500 mg ASA. Conclusion: Our modified schema of IPT with L-ASA up to a cumulative dose of 60 mg L-ASA is suitable for diagnosing an AIA in an ambulatory setting. The IPT with L-ASA is a sensitive and safe provocation test lasting about 3 h. A negative IPT at 60 mg L-ASA excludes a significant reaction following the intake of low-dose aspirin (100 - 300 mg), this information may be essential in the prophylaxis and treatment of cardiovascular diseases.