Interleukin-4 and interleukin-13 concentrations in bronchoalveolar lavage fluid in neonates with respiratory distress syndrome and concurrent ventilator-associated pneumonia

OBJECTIVE: To study the concentrations of IL-4 and IL-13 in bronchoalveolar lavage fluid (BALF) in neonates with respiratory distress syndrome (RDS) and concurrent ventilator-associated pneumonia (VAP). METHODS: Sixty-eight neonates with RDS undergoing mechanical ventilation for over 48 hrs were enrolled. IL-4 and IL-13 levels in BALF were measured using ELISA 1, 72 and 96 hrs after mechanical ventilation. The results were compared between the neonates with concurrent VAP (n=37) and without (n=31). RESULTS: The levels of BALF IL-4 96 hrs after ventilation in the VAP group (35.34+/-1.78 ng/mL) were significantly higher than those in the non-VAP group (13.69+/-2.47 ng/mL, P<0.05). The levels of BALF IL-13 96 hrs after ventilation in the VAP group (33.74+/-2.74 ng/mL) also increased significantly compared with those in the non-VAP group (13.50+/-3.81 ng/mL) (P<0.05). There were significant differences in BALF IL-4 and IL-13 levels between 1 hr and 96 hrs in the VAP group (P<0.05). CONCLUSIONS: BALF IL-4 and IL-13 levels increase in neonates with RDS and concurrent VAP. IL-4 and IL-13 may involve in the regulation of the inflammatory immune response.