title: Transient sputum eosinophilia may occur over time in non-eosinophilic asthma and this is not prevented by salmeterol.
abstract: OBJECTIVE
  Symptomatic, steroid-naïve asthmatic patients may have low sputum eosinophil numbers. The aim of the study was to determine whether low sputum eosinophil numbers persisted over time, during treatment with salmeterol monotherapy.
  
  
  METHODS
  Forty steroid-naïve, symptomatic asthmatic patients, with sputum eosinophils <3%, were randomized to receive open-label salmeterol (50 µg twice a day, n = 30) or fluticasone (125 µg twice a day, n = 10) and were then assessed at 1, 3 and 6 months. All patients underwent spirometry, a methacholine challenge test and sputum induction at each visit. Symptom scores and peak expiratory flow were recorded throughout the study. Patients were permitted to withdraw from the study at any time, if they experienced exacerbations or deterioration of symptoms.
  
  
  RESULTS
  The average sputum eosinophil percentage remained normal (≤1.9%) in both groups over the study period. The eosinophil percentages were ≤1.9% in 65 of the 80 samples obtained from salmeterol-treated patients throughout the study period. Eight patients had an asthma exacerbation or deterioration, during which one developed sputum eosinophilia. Twelve patients, 11 of whom were randomized to salmeterol and one to fluticasone, developed transient sputum eosinophilia at least once during the study. This was not associated with asthma exacerbation (except for one patient). Sputum neutrophil percentage did not change in either group.
  
  
  CONCLUSIONS
  Low sputum eosinophil numbers persisted over 6 months in a majority of patients with non-eosinophilic asthma who received salmeterol monotherapy. However, transient sputum eosinophilia occurred in 40% indicating that non-eosinophilic asthma may not be a stable phenotype.
authors.affiliation: CardioThoracic and Vascular Department, Pneumology Section, University of Pisa, Pisa, Italy.
authors.forename: Elena
authors.initials: E
authors.lastname: Bacci
authors.forename: Manuela
authors.initials: M
authors.lastname: Latorre
authors.forename: Silvana
authors.initials: S
authors.lastname: Cianchetti
authors.forename: Marialaura
authors.initials: M
authors.lastname: Bartoli
authors.forename: Francesco
authors.initials: F
authors.lastname: Costa
authors.forename: Antonella
authors.initials: A
authors.lastname: Di Franco
authors.forename: Laura
authors.initials: L
authors.lastname: Malagrinò
authors.forename: Federica
authors.initials: F
authors.lastname: Novelli
authors.forename: Barbara
authors.initials: B
authors.lastname: Vagaggini
authors.forename: Federico L
authors.initials: FL
authors.lastname: Dente
authors.forename: Pierluigi
authors.initials: P
authors.lastname: Paggiaro
mesh_terms: D000328:Adult; D000420:Albuterol / Q000009:adverse effects / Q000031:analogs & derivatives* / Q000627:therapeutic use; D000730:Androstadienes / Q000009:adverse effects / Q000627:therapeutic use; D001249:Asthma / Q000175:diagnosis / Q000188:drug therapy*; D001993:Bronchodilator Agents / Q000009:adverse effects / Q000627:therapeutic use*; D004802:Eosinophilia / Q000139:chemically induced*; D005260:Female; D000068298:Fluticasone; D006801:Humans; D008297:Male; D016210:Methacholine Chloride; D008875:Middle Aged; D009504:Neutrophils / Q000187:drug effects; D000068299:Salmeterol Xinafoate; D013183:Sputum / Q000166:cytology*; D055815:Young Adult
chemical_list: D000730:Androstadienes; D001993:Bronchodilator Agents; D016210:Methacholine Chloride; D000068299:Salmeterol Xinafoate; D000068298:Fluticasone; D000420:Albuterol