Interleukin-1beta in the bronchoalveolar lavage fluid of premature neonates: a marker for maternal chorioamnionitis and predictor of adverse neonatal outcome

J Matern Fetal Neonatal Med. 2003 Sep;14(3):205-11. doi: 10.1080/jmf.


Objective: To determine whether the presence of the proinflammatory cytokine interleukin (IL)-1beta in the lungs of preterm infants immediately after birth was associated with maternal inflammation and could predict adverse neonatal outcome.

Study design: Prospective evaluation of serially obtained tracheal aspirates for the presence of IL-1beta in 25 preterm infants (birth weight 595-1700 g; gestational age 24-32 weeks) with respiratory distress syndrome. The initial tracheal aspirate was obtained within 1 h after delivery.

Results: An initial tracheal aspirate positive for IL-1beta had a highly significant correlation with documented maternal chorioamnionitis for the given patient. In addition, the presence of IL-1beta correlated significantly with elevated total cell count (2.62 vs. 0.96 x 10(6)/ml, p = 0.0097), granulocyte count (2.12 vs. 0.22 x 10(6)/ml, p = 0.001), macrophage count (0.28 vs. 0.01 x 10(6)/ml, p = 0.02) and the presence of proinflammatory cytokines IL-6, IL-8 and tumor necrosis factor (TNF)-alpha. Preterm neonates positive for IL-1beta in their initial sample were on prolonged assisted ventilation (38 vs. 16 days, p = 0.013) and oxygen supplementation (62 vs. 40.5 days, p = 0.0462) and required prolonged hospitalization (69 vs. 46 days, p = 0.0165).

Conclusions: The concentration of IL-1beta in the initial tracheal aspirate obtained from the lungs of preterm infants within the first hour of life may serve as a marker of antenatal/perinatal inflammation, probably due to maternal chorioamnionitis, and could predict an adverse clinical course and short-term outcome.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Biomarkers / analysis
  • Bronchoalveolar Lavage Fluid / cytology*
  • Cesarean Section / statistics & numerical data
  • Chorioamnionitis / immunology*
  • Cytokines / metabolism
  • Female
  • Humans
  • Infant, Newborn
  • Infant, Premature / metabolism*
  • Interleukin-1 / metabolism*
  • Intubation, Intratracheal
  • Length of Stay / statistics & numerical data
  • Male
  • Outcome Assessment, Health Care
  • Oxygen Inhalation Therapy
  • Pregnancy
  • Prospective Studies
  • Respiration, Artificial
  • Respiratory Distress Syndrome, Newborn / immunology
  • Respiratory Distress Syndrome, Newborn / metabolism


  • Biomarkers
  • Cytokines
  • Interleukin-1