title: Blood eosinophil counts during bronchiolitis are related to bronchial hyper-responsiveness and lung function in early adolescence.
abstract: OBJECTIVE
  To assess whether inflammatory markers measured in urine and blood during acute bronchiolitis in infancy were associated with asthma, lung function, bronchial hyper-responsiveness (BHR) and atopy at 11 years of age.
  
  
  METHODS
  We included 105 children hospitalised for bronchiolitis during their first year of life. At hospitalisation, urinary (U-) eosinophil protein X, U-leukotriene E4 , U-prostaglandin 9α, 11β-PGF2 and blood eosinophil counts were measured. Ninety-five children (90%) were available for follow-up at 11 years of age.
  
  
  RESULTS
  At follow-up, higher blood eosinophil counts obtained during bronchiolitis were observed in the group with asthma than in the group without asthma (median 0.27 versus 0.09 × 10(9) /L, respectively, p = 0.048). By regression analyses, blood eosinophil counts during the acute bronchiolitis were positively associated with BHR (p = 0.006) and negatively associated with forced expiratory volume in first second (p = 0.025) at 11 years of age. None of the other inflammatory markers were associated with asthma, lung function, BHR or atopy at 11 years of age.
  
  
  CONCLUSIONS
  Eosinophil inflammation during bronchiolitis may have a long-term impact on lung function and airway responsiveness. The associations could be related to virus-host interactions during bronchiolitis or to predisposed children.
authors.affiliation: Department of Paediatrics, Stavanger University Hospital, Stavanger, Norway.
authors.forename: Ingvild Bruun
authors.initials: IB
authors.lastname: Mikalsen
authors.forename: Thomas
authors.initials: T
authors.lastname: Halvorsen
authors.forename: Knut
authors.initials: K
authors.lastname: Øymar
mesh_terms: D001249:Asthma / Q000209:etiology*; D016535:Bronchial Hyperreactivity / Q000209:etiology*; D001988:Bronchiolitis / Q000097:blood / Q000150:complications* / Q000276:immunology* / Q000652:urine; D002648:Child; D004804:Eosinophils; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007223:Infant; D007958:Leukocyte Count; D016014:Linear Models; D008297:Male; D008407:Mast Cells; D011446:Prospective Studies; D012129:Respiratory Function Tests
keywords: Asthma in children; Bronchial hyper-reactivity; Bronchiolitis; Inflammatory mediators; Lung function