title: Early increase in endothelin-1 in tracheal aspirates of preterm infants: correlation with bronchopulmonary dysplasia.
abstract: OBJECTIVE
  To determine whether endothelin-1 (ET-1) in tracheal aspirates (TA) is a specific marker for acute lung injury in preterm infants with respiratory distress syndrome (RDS) who progress to bronchopulmonary dysplasia (BPD); and to investigate the relationship between TA ET-1 and the proinflammatory cytokines, interleukin-6 (IL-6) and IL-8, as early mediators of BPD.
  
  
  METHODS
  We measured TA ET-1, IL-6, and IL-8 levels in preterm infants whose lungs were mechanically ventilated for RDS, categorized into two groups, BPD or non-BPD, on the basis of oxygen requirement at 36 weeks' postconceptional age.
  
  
  RESULTS
  A total of 106 TA samples were obtained from 34 infants with gestational ages ranging from 24 to 28 weeks on days 1, 3, 5, and 7 of life. There was a wide range of ET-1 concentration. TA ET-1 levels were significantly elevated on days 1, 3, and 7 in infants in whom BPD developed, in comparison with the non-BPD group (Mann-Whitney U test: p < 0.01). TA IL-8 levels were elevated on days 1, 3, 5, and 7 in the BPD group (p < 0.01); TA IL-6 levels were elevated (p < 0.05) only on day 5. There was a similarity in pattern of increase of TA ET-1 and TA IL-8 levels in the BPD group, with both being elevated in the first 24 hours of life and through the first week. There was no correlation between ET-1 and IL-8 values.
  
  
  CONCLUSIONS
  Early significant increase in the TA ET-1 and IL-8 concentrations in preterm infants with acute lung injury correlates with subsequent progression to BPD.
authors.affiliation: Department of Pediatrics (Division of neonatal Medicine), State University of New York at Stony Brook 11794-8111, USA.
authors.forename: J O
authors.initials: JO
authors.lastname: Niu
authors.forename: U K
authors.initials: UK
authors.lastname: Munshi
authors.forename: M M
authors.initials: MM
authors.lastname: Siddiq
authors.forename: L A
authors.initials: LA
authors.lastname: Parton
mesh_terms: D015415:Biomarkers / Q000032:analysis; D001997:Bronchopulmonary Dysplasia / Q000175:diagnosis / Q000378:metabolism*; D016022:Case-Control Studies; D019332:Endothelin-1 / Q000378:metabolism*; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D015850:Interleukin-6 / Q000378:metabolism; D016209:Interleukin-8 / Q000378:metabolism; D008297:Male; D012121:Respiration, Artificial; D013997:Time Factors; D014132:Trachea / Q000378:metabolism
chemical_list: D015415:Biomarkers; D019332:Endothelin-1; D015850:Interleukin-6; D016209:Interleukin-8