Early increase of TNF alpha and IL-6 in tracheobronchial aspirate fluid indicator of subsequent chronic lung disease in preterm infants

Aim-To investigate if early changes in concentrations of proinflammatory cytokines in tracheobronchial aspirate fluid (TAF) from preterm infants could be used to detect infants at risk of chronic lung disease (CLD) and help in the selection of patients for early steroid treatment. Methods-Twenty eight preterm infants less than 34 weeks of gestation (median 26 weeks) were intubated and daily measurements of TAF concentration of tumour necrosis factor alpha (TNF alpha) and the interleukins IL-1 beta, IL-6, and IL-8 were made, using enzyme immunoassay techniques. Results-Seventeen of the infants developed CLD. The infants who developed CLD had significantly increased concentrations of TNF alpha, IL-1 beta, IL-6 on days 2 and 3. TNF alpha, IL-6, and IL-8 concentrations were significantly related to gestational age and duration of supplemental oxygen; TNF alpha, IL-6, and IL-8 concentrations also correlated with length of time on the ventilator. Conclusion-These data indicate that tracheobronchial aspirate fluid cytokine concentrations may be used as a predictor of subsequent CLD and may help select a group of preterm infants at high risk of developing CLD for early treatment.