A study on the dynamic changes of S-100 B protein for the early diagnosis of neonatal hypoxic ischemic encephalopathy

Objective To study the dynamic changes of the S-100B protein level for early diagnosis of neonatal hypoxic-ischemic encephalopathy(HIE).Methods From May 2009 to May 2011,neonates with mild-to-severe asphyxia admitted to neonatal intensive care unit and 40 healthy neonates born in the hospital were enrolled into the study.Serum S-100B protein levels within 6 hours after birth and(72 ± 6) h were compared between these groups and the diagnosis value for HIE were assessed.Results Mild asphyxia group and severe asphyxia group had higher S-100B protein levels than that of the the control group within 6 hours after birth [(0.40 ± 0.24) μg / L,(0.89 ± 0.34) μg / L vs.(0.28 ± 0.14) μg / L,P 0.01 ],severe asphyxia group even higher than the mild group.72 h after birth,S-100B protein levels in mild asphyxia group showed no significant differences than the control group(P 0.05),severe asphyxia group still had higher S-100B protein level than the mild group [(0.44 ± 0.21) μg / L vs.(0.26 ± 0.10) μg / L,P 0.01].S-100B protein levels in neonates with asphyxia and intracranial hemorrhage were higher than that of the severe asphyxia group within 6 h and 72 h after birth [(2.61 ±1.08) μg/L vs.(0.89 ± 0.34) μg/L,(1.64 ± 0.71) μg/L vs.(0.44 ± 0.21) μg/L,P 0.01].The sensitivity and negative predictive value of S-100B protein level for the diagnosis of HIE within 6 h after birth were 97.4% and 97.7%,but specificity and positive predictive value were lower.The specificity and positive predictive value of S-100B protein level for the diagnosis of HIE at 72 h were 100%,but sensitivity and negative predictive value were lower.Therefore,serum S-100B protein level within 6 h could be considered for use as a preliminary screening test for HIE,combining with resampling at 72 h to improve the specificity for the diagnosis of severe HIE.Conclusions Serum S-100B protein level in asphyxia neonates could be used as a sensitive indicator(index) of early brain damage and objective evidence for early diagnosis and intervention of HIE.