Oral and bronchial provocation tests with aspirin for diagnosis of aspirin-induced asthma

In 35 asthmatic patients with acetylsalicylic acid (aspirin; ASA) intoleran ce (AIA) and 15 asthmatics tolerating ASA well, the authors compared the di agnostic value of the placebo-controlled oral ASA versus inhaled L-lysine ( L) ASA challenges. All AIA subjects gave a history of asthmatic attacks following ingestion of ASA and in all of them the intolerance was confirmed by oral challenge tes t over the past 10 yrs. Doses of ASA increasing in geometric progression we re used in oral tests 10-312 mg (cumulative dose 500 mg); in bronchial test s 0.18-115 mg (cumulative dose 182 mg). Either challenge was considered as positive, if forced expiratory volume in one second (FEV1) dropped at least 20% from the baseline value and/or strong extrabronchial symptoms of intol erance occurred. Urinary leukotriene E-4 excretion was determined at baseli ne and following the challenges. In 24 out of 35 patients the oral test was positive, based on a 20% decreas e in FEV1. When including extrabronchial symptoms this was positive in 31 c ases. Bronchial LASA challenge led to greater than or equal to 20% fall FEV 1 in 21 out of 35 cases, and in 27 cases when including extrabronchial symp toms. No correlation was observed between ASA provocative dose causing a 20 % fall in FEV1, determined by the oral route compared to the inhalation rou te. Urinary LTE4 increased after both challenges the rise being higher foll owing oral as compared to inhalation provocation (p=0.0001). It is concluded that both tests had similar specificity whilst the oral tes t showed a tendency to higher sensitivity for the clinical diagnosis of ace tylsalicylic acid intolerance. The inclusion of extrabronchial symptoms int o the criteria of test positivity enhanced the diagnostic value of both pro cedures. In both tests the highest leukotriene E-4 increases were found in the presence of extrabronchial symptoms, suggesting the participation of ti ssues other than the lung in aspirin induced leukotriene E-4 release to uri ne.