Interleukin-6 in preterm premature rupture of membranes as an indicator of neonatal outcome

Abstract

Background: The aim of this study was to investigate whether the levels of interleukin-6 (IL-6) can be used as markers of adverse outcome in preterm neonates born after preterm premature rupture of membranes (PPROM).

Methods: This study involved 109 preterm neonates and their mothers. The PPROM group consisted of 58 neonates who were born after PPROM, and the control group consisted of 51 neonates. IL-6 levels were measured in umbilical cord blood, maternal blood sampled during delivery and in neonatal blood taken on the fourth day of life.

Results: In the PPROM group, IL-6 concentrations in maternal blood, cord blood, and neonatal blood were significantly higher in neonates with sepsis, compared with those without sepsis (P < 0.001). Choosing 108.5 pg/ml as a cut-off concentration of IL-6 in umbilical cord blood for neonatal sepsis resulted in sensitivity 95%, specificity 100%, positive predictive value 100%, and negative predictive value 97.4%. Concerning IL-6 in maternal blood, a cut-off concentration of 81 pg/ml showed sensitivity 90%, specificity 97.4%, positive predictive value 94.7%, and negative predictive value 94.9%. Eighteen of 20 neonates with early sepsis and seven of nine neonates, who died in the PPROM group, were born of mothers with IL-6 levels above the cut-off concentration in their blood during delivery.

Conclusions: IL-6 in umbilical cord blood was the most significant variable for predicting early onset sepsis in preterm neonates. IL-6 in maternal blood was indicative of intrauterine environmental threats and might be used to identify pregnancies where intervention would be appropriate.