title: Infection, inflammation, and lung function decline in infants with cystic fibrosis.
abstract: BACKGROUND
  Better understanding of evolution of lung function in infants with cystic fibrosis (CF) and its association with pulmonary inflammation and infection is crucial in informing both early intervention studies aimed at limiting lung damage and the role of lung function as outcomes in such studies.
  
  
  OBJECTIVE
  To describe longitudinal change in lung function in infants with CF and its association with pulmonary infection and inflammation.
  
  
  METHODS
  Infants diagnosed after newborn screening or clinical presentation were recruited prospectively. FVC, forced expiratory volume in 0.5 seconds (FEV(0.5)), and forced expiratory flows at 75% of exhaled vital capacity (FEF(75)) were measured using the raised-volume technique, and z-scores were calculated from published reference equations. Pulmonary infection and inflammation were measured in bronchoalveolar lavage within 48 hours of lung function testing.
  
  
  RESULTS
  Thirty-seven infants had at least two successful repeat lung function measurements. Mean (SD) z-scores for FVC were -0.8 (1.0), -0.9 (1.1), and -1.7 (1.2) when measured at the first visit, 1-year visit, or 2-year visit, respectively. Mean (SD) z-scores for FEV(0.5) were -1.4 (1.2), -2.4 (1.1), and -4.3 (1.6), respectively. In those infants in whom free neutrophil elastase was detected, FVC z-scores were 0.81 lower (P=0.003), and FEV(0.5) z-scores 0.96 lower (P=0.001), respectively. Significantly greater decline in FEV(0.5) z-scores occurred in those infected with Staphylococcus aureus (P=0.018) or Pseudomonas aeruginosa (P=0.021).
  
  
  CONCLUSIONS
  In infants with CF, pulmonary inflammation is associated with lower lung function, whereas pulmonary infection is associated with a greater rate of decline in lung function. Strategies targeting pulmonary inflammation and infection are required to prevent early decline in lung function in infants with CF.
authors.affiliation: Department of Respiratory Medicine, Royal Children's Hospital Melbourne, Flemington Road, Parkville, 3052, Australia.
authors.forename: Naveen
authors.initials: N
authors.lastname: Pillarisetti
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Williamson
authors.forename: Barry
authors.initials: B
authors.lastname: Linnane
authors.forename: Billy
authors.initials: B
authors.lastname: Skoric
authors.forename: Colin F
authors.initials: CF
authors.lastname: Robertson
authors.forename: Phil
authors.initials: P
authors.lastname: Robinson
authors.forename: John
authors.initials: J
authors.lastname: Massie
authors.forename: Graham L
authors.initials: GL
authors.lastname: Hall
authors.forename: Peter
authors.initials: P
authors.lastname: Sly
authors.forename: Stephen
authors.initials: S
authors.lastname: Stick
authors.forename: Sarath
authors.initials: S
authors.lastname: Ranganathan
mesh_terms: D001992:Bronchoalveolar Lavage Fluid / Q000737:chemistry / Q000166:cytology; D003550:Cystic Fibrosis / Q000150:complications / Q000175:diagnosis / Q000382:microbiology / Q000503:physiopathology*; D018450:Disease Progression; D005260:Female; D005541:Forced Expiratory Volume; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D015997:Neonatal Screening; D011014:Pneumonia / Q000150:complications*; D011552:Pseudomonas Infections / Q000150:complications*; D012129:Respiratory Function Tests; D012141:Respiratory Tract Infections / Q000150:complications*; D013203:Staphylococcal Infections / Q000150:complications*; D014797:Vital Capacity