NASAL PROVOCATION TEST WITH LYSINE-ASPIRIN FOR DIAGNOSIS OF ASPIRIN-SENSITIVE ASTHMA

Nasal provocation tests (NPTs) with lysine-aspirin (L-ASA) have been r ecently introduced for assessment of aspirin-induced asthma (AIA). The y differ in dose and means of aspirin instillation, duration of observ ation period, and criteria for positivity. Thus far they have not beco me a routine part of clinical diagnosis. Fifty-one patients with AIA, confirmed by oral challenge test, were recruited to undergo diagnostic NPTs with L-ASA. In 10 of these patients (19.6%), NPTs could not be p erformed because of total obstruction of at least one nostril or marke d fluctuations in nasal hows, leaving 41 patients with AIA for the stu dy. Control groups consisted of 13 aspirin-tolerant asthmatic patients and 10 healthy subjects. L-ASA at a total dose of 16 mg of acetylsali cylic acid applied bilaterally into the inferior nasal conchae caused significant fall in inspiratory nasal how in at least one nostril (>40 %), which nas measured by anterior rhinomanometry, and clinical Sympto ms of watery discharge and nasal blockage in 35 of 41 patients with AI A, one of 10 healthy subjects, and none of 13 aspirin-tolerant asthmat ic patients. No relationship was found between the baseline nasal flow values and the intensity of response to L-ASA. No systemic: reactions , including bronchospasm, were noticed, even in patients whose initial FEV1 was lower than 70% of predicted value. This test is highly speci fic (95.7%) and sensitive (86.7%), but negative results do not exclude possible intolerance to aspirin (predictive value of a negative resul t 78.6%). In conclusion, the NPT described is a simple, safe, and quic k test for diagnosis of AIA. It can be used in patients with unstable asthma. It may be a method of choice to confirm hypersensitivity to as pirin manifested only by symptoms from the upper respiratory tract. Pa tients suspected of aspirin intolerance who have negative NPT results should undergo bronchial or oral challenge tests with aspirin.