title: Bronchial inflammation and hyperresponsiveness in well controlled asthma.
abstract: BACKGROUND
  Little research has been devoted to the characteristics of bronchial inflammation in patients with stable, well controlled asthma.
  
  
  OBJECTIVE
  The aim of this study was to assess the degree and type of airway inflammation and to investigate the relationship between inflammation and bronchial hyperresponsiveness in patients with well controlled asthma.
  
  
  METHODS
  A cross-sectional study was conducted in 84 adult patients (43 men, mean age 43 years) with documented well controlled asthma. Induced sputum samples were obtained and cell types determined by differential cell count. Spirometry and methacholine challenge testing were performed. Asthma Control Questionnaire (ACQ) was used to assess symptoms. Patients were included if their ACQ score was < 0.75.
  
  
  RESULTS
  A total of 59 patients had persistent bronchial inflammation: 28 cases were considered eosinophilic, 28 neutrophilic, and 3 mixed. Median (range) percentage of eosinophils was 4% (0-64) in patients testing positive to methacholine challenge (n = 66) and 1% (0-3) in those testing negative (n = 18) (P = 0.003). A positive correlation was found between eosinophil percentage and the methacholine dose/response ratio (r = 0.477, P = 0.0001). The geometric mean (95% CI) of the methacholine PC20 was 1.74 mg/mL (1.04-2.93) in patients with eosinophilic inflammation and 4.14 mg/mL (2.5-6.84) in those with neutrophilic inflammation (P = 0.03).
  
  
  CONCLUSIONS
  Inflammation and bronchial hyperresponsiveness persist in most patients with well controlled asthma.
  
  
  CONCLUSIONS
  The study demonstrates that eosinophilic or neutrophilic inflammation persisted in most well controlled asthma patients despite the fact that their condition was controlled and therefore, measurement of bronchial inflammation seems essential to achieve proper asthma control.
authors.affiliation: Pulmonology Service, Medicine Department, Hospital Vall d'Hebron, Universitat Autònoma de Barcelona, Barcelona, Spain. xmunoz@vhebron.net
authors.forename: X
authors.initials: X
authors.lastname: Muñoz
authors.forename: S
authors.initials: S
authors.lastname: Sanchez-Vidaurre
authors.forename: O
authors.initials: O
authors.lastname: Roca
authors.forename: F
authors.initials: F
authors.lastname: Torres
authors.forename: F
authors.initials: F
authors.lastname: Morell
authors.forename: M J
authors.initials: MJ
authors.lastname: Cruz
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001249:Asthma / Q000503:physiopathology* / Q000517:prevention & control*; D016535:Bronchial Hyperreactivity / Q000276:immunology / Q000503:physiopathology; D001985:Bronchial Provocation Tests; D003430:Cross-Sectional Studies; D004804:Eosinophils / Q000166:cytology / Q000276:immunology; D005260:Female; D006801:Humans; D006969:Hypersensitivity, Immediate / Q000276:immunology / Q000503:physiopathology; D007249:Inflammation / Q000276:immunology / Q000503:physiopathology; D008297:Male; D016210:Methacholine Chloride / Q000008:administration & dosage; D008875:Middle Aged; D009504:Neutrophils / Q000166:cytology / Q000276:immunology; D013147:Spirometry; D013183:Sputum / Q000166:cytology / Q000378:metabolism; D055815:Young Adult
chemical_list: D016210:Methacholine Chloride