High cord blood IL-10 levels in preterm newborns with respiratory distress syndrome.

BACKGROUND The development of respiratory distress syndrome (RDS) is closely related to fetal immaturity, although the participation of inflammatory mechanisms also seems to be likely. We previously reported high interleukin-10 (IL-10) levels in cord blood from preterm infants. In the present study, we investigate the possible role of IL-10 and IL-12 in preterm newborns with RDS, a disease that is also closely related to gestational age. PATIENTS AND METHODS Cord blood levels of IL-10 and IL-12 (p70 + p40) were determined by ELISA in 20 preterm infants who later developed RDS, in 21 preterm infants without RDS and in 31 full term newborns. In 11 patients follow-up samples could be also obtained between 2 and 14 days of life. RESULTS Preterm infants with RDS showed higher IL-10 (27 vs 10.8 pg/mL; p: 0.0003) and lower IL-12 (188 vs 384; p: 0.002) levels in cord blood than premature infants without RDS and full term newborns (IL-10: 3.2 pg/mL, p: 0.0001; IL-12: 352 pg/mL; p: 0.002). The differences remained statistically significant after correction for the effect of gestational age between both preterm groups. CONCLUSIONS The results obtained may be related to an immature cytokine response in premature infants, but the IL-12/IL-10 imbalance found in our patients also supports the hypothesis that inflammation plays a role in RDS.