title: Airway responsiveness to adenosine after a single dose of fluticasone propionate discriminates asthma from COPD.
abstract: BACKGROUND
  Regular treatment with inhaled corticosteroids (ICS) is known to reduce airway hyperresponsiveness (AHR) to adenosine 5'-monophosphate (AMP) in asthma even after a single dose of fluticasone propionate (FP).
  
  
  OBJECTIVE
  To determine whether this rapid protective effect of a single dose of FP is also present in COPD.
  
  
  METHODS
  23 mild asthmatic and 24 COPD subjects with documented AHR to both AMP and methacholine took part in a randomized, double-blind, placebo-controlled, crossover study to measure AHR to inhaled AMP and methacholine 2 h after either 1000 μg FP or matched placebo.
  
  
  RESULTS
  In subjects with asthma, 1000 μg FP in a single dose significantly attenuated the constrictor response to AMP, geometric mean (range) PC20AMP values increasing from a 19.2 (1.3-116.3) to 81.5 (9.6-1600.0) (p < 0.001; post-placebo vs post-FP) mg/ml. Change in the airways response to inhaled AMP after FP was well within test variability in patients with COPD, with PC20AMP values 59.6 (11.3-183.9) and 76.3 (21.0-445.3) (p = 0.022; post-placebo vs post-FP) mg/ml. Additionally, FP failed to significantly attenuate the bronchial response to methacholine in both asthma and COPD subjects. A change in doubling dilution, between placebo and following a single dose of FP, in AMP had a better sensitivity and specificity of 95.8% and 65.2%, compared to methacholine of 79.2% and 43.5% respectively in delineating between COPD and asthma.
  
  
  CONCLUSIONS
  A single dose of 1000 μg FP rapidly improves AHR to AMP in asthmatics but not in COPD subjects. This may provide a convenient way by which provocation challenge with inhaled AMP may help in discriminating asthma from COPD.
authors.affiliation: Dipartimento di Medicina Interna e Specialistica, Sez. Malattie Apparato Respiratorio, Università di Catania, Catania, Italy.
authors.forename: Lucia
authors.initials: L
authors.lastname: Spicuzza
authors.affiliation: Dipartimento di Medicina Interna e Specialistica, Sez. Malattie Apparato Respiratorio, Università di Catania, Catania, Italy.
authors.forename: Vincenza
authors.initials: V
authors.lastname: Scuderi
authors.affiliation: Dept of Cardiovascular and Respiratory Studies, Hull York Medical School, University of Hull, Castle Hill Hospital, Cottingham, UK.
authors.forename: Jaymin B
authors.initials: JB
authors.lastname: Morjaria
authors.affiliation: Dipartimento di Medicina Interna e Specialistica, Sez. Medicina Interna, Università di Catania, Catania, Italy.
authors.forename: Gaetano
authors.initials: G
authors.lastname: Prosperini
authors.affiliation: Dipartimento di Medicina Interna e Specialistica, Sez. Medicina Interna, Università di Catania, Catania, Italy.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Arcidiacono
authors.affiliation: Dipartimento di Medicina Interna e Specialistica, Sez. Medicina Interna, Università di Catania, Catania, Italy.
authors.forename: Massimo
authors.initials: M
authors.lastname: Caruso
authors.affiliation: Dipartimento di Medicina Interna e Specialistica, Sez. Malattie Apparato Respiratorio, Università di Catania, Catania, Italy.
authors.forename: Caterina
authors.initials: C
authors.lastname: Folisi
authors.affiliation: Dipartimento di Medicina Interna e Specialistica, Sez. Malattie Apparato Respiratorio, Università di Catania, Catania, Italy.
authors.forename: Giuseppe U
authors.initials: GU
authors.lastname: Di Maria
authors.affiliation: Dipartimento di Medicina Interna e Specialistica, Sez. Medicina Interna, Università di Catania, Catania, Italy. Electronic address: polosa@unict.it.
authors.forename: Riccardo
authors.initials: R
authors.lastname: Polosa
mesh_terms: D000249:Adenosine Monophosphate; D000280:Administration, Inhalation; D000328:Adult; D000368:Aged; D000730:Androstadienes / Q000008:administration & dosage / Q000494:pharmacology*; D001249:Asthma / Q000175:diagnosis* / Q000188:drug therapy / Q000503:physiopathology; D016535:Bronchial Hyperreactivity / Q000188:drug therapy / Q000209:etiology; D001993:Bronchodilator Agents / Q000008:administration & dosage / Q000494:pharmacology; D018592:Cross-Over Studies; D004311:Double-Blind Method; D005260:Female; D000068298:Fluticasone; D006801:Humans; D008297:Male; D016210:Methacholine Chloride; D008875:Middle Aged; D029424:Pulmonary Disease, Chronic Obstructive / Q000175:diagnosis* / Q000188:drug therapy / Q000503:physiopathology; D012680:Sensitivity and Specificity
chemical_list: D000730:Androstadienes; D001993:Bronchodilator Agents; D016210:Methacholine Chloride; D000249:Adenosine Monophosphate; D000068298:Fluticasone
keywords: Adenosine 5′-monophosphate; Airway hyperresponsiveness; Asthma; COPD; Fluticasone propionate