[Induced sputum supernatant prostaglandin E2 during oral aspirin challenge of asthmatic patients with and without aspirin hypersensitivity and healthy controls--pilot study].

The aim of this pilot study was to evaluate changes in the concentration of prostaglandin E2 (PGE2) in induced sputum supernatant in 3 groups: sub- jects with NSAID-exacerbated respira- tory disease (NERD), aspirin tolerant asthma (ATA) and healthy controls (HC), before and after oral aspirin chal- lenge test. The study was conducted in the years 2014-2015 at the Clinical Department of the Pulmonology Clinic at the University Hospital in Cracow. 43 patients were enrolled in the study (NERD - n = 15, ATA - n = 15 and HC - n = 13). All of them underwent a placebo-controlled oral aspirin challenge. Sputum was induced 24 hours before the challenge and immediately after the test. Induced sputum was processed in order to obtain cystospin slides to depict inflammatory cell patterns and supernatants, in which PGE2 was measured. The concentration of PGE2 was determined using mass spectrometry coupled with gas chromatography (gas chromatography/mass spectrometry - GC/MS). After aspirin challenge, the concentration of PGE2 in induced sputum supernatant decreased in both asthmatics hypersensitive to aspirin (p = 0.01) and those who tolerated aspirin well (p = 0.17). The change in the healthy control group was not statistically significant. These results support the cyclooxygenase theory of PGE2 inhibition by aspirin. However, the mechanism of bronchoconstriction after aspirin administration alone in patients with NSAID-exacerbated respiratory disease remains unclear.