title: Effect of inhalation aspirin challenge on exhaled nitric oxide in patients with aspirin-inducible asthma.
abstract: BACKGROUND
  A complex relationship between arachidonic acid metabolites and nitric oxide (NO) synthesis has been reported in asthma. The effects of inhaled aspirin on fractional exhaled NO (FENO) in patients with aspirin-tolerant (ATA) and aspirin-inducible (AIA) asthma compared with normal controls have been investigated.
  
  
  METHODS
  The FENO was measured baseline, after saline and lysine-aspirin (L-ASA) bronchial challenge in 10 patients with ATA and in 10 patients with AIA [mean (PD(20)FEV(1) L-ASA): 14.7 +/- 12.7 mg], who had comparable age and baseline FEV(1). Ten healthy subjects served as controls. Sputum eosinophils were counted after saline and after L-ASA challenge in the two groups of asthmatics.
  
  
  RESULTS
  Asthmatic patients had baseline FENO significantly higher than controls (29.7 +/- 6.8 vs 9.8 +/- 2.05 p.p.b. respectively, P < 0.0001). No difference was observed in methacholine PD(20)FEV(1) and baseline FENO between ATA and AIA patients. After L-ASA inhalation, FENO increased significantly only in patients with AIA, reaching the peak value 4 h after bronchoconstriction (from 31.1 +/- 6 to 43 +/- 4.8 p.p.b., P < 0.001), while no change was observed in patients with ATA and in controls. Sputum eosinophils increased significantly after L-ASA inhalation only in patients with AIA (from 8.1 +/- 2.7 to 11.1 +/- 2.8%, P < 0.005) and there was a significant relationship between the increase in sputum eosinophils and the increase in FENO after ASA challenge.
  
  
  CONCLUSIONS
  Exhaled NO may indicate eosinophilic airway inflammation during ASA exposure in patients with ASA inducible asthma.
authors.affiliation: Allergologia e Immunologia Cinica, Università di Torino and Ospedale Mauriziano Umberto I di Torino, Largo Turati 62, 10128 Turin, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Rolla
authors.forename: A
authors.initials: A
authors.lastname: Di Emanuele
authors.forename: L
authors.initials: L
authors.lastname: Dutto
authors.forename: P
authors.initials: P
authors.lastname: Marsico
authors.forename: F
authors.initials: F
authors.lastname: Nebiolo
authors.forename: F
authors.initials: F
authors.lastname: Corradi
authors.forename: L
authors.initials: L
authors.lastname: Brussino
authors.forename: C
authors.initials: C
authors.lastname: Bucca
mesh_terms: D000280:Administration, Inhalation; D000328:Adult; D000368:Aged; D001241:Aspirin / Q000008:administration & dosage* / Q000009:adverse effects*; D001249:Asthma / Q000139:chemically induced* / Q000378:metabolism; D001944:Breath Tests; D004311:Double-Blind Method; D004804:Eosinophils / Q000502:physiology; D005260:Female; D005541:Forced Expiratory Volume / Q000187:drug effects; D006801:Humans; D008297:Male; D008875:Middle Aged; D009569:Nitric Oxide / Q000378:metabolism*; D013183:Sputum / Q000166:cytology
chemical_list: D009569:Nitric Oxide; D001241:Aspirin