ELEVATION OF ACTIVITY OF CREATINE-PHOSPHOKINASE (CK) AND ITS ISOENZYMES IN THE NEWBORN IS ASSOCIATED WITH FETAL ASPHYXIA AND RISK AT BIRTH

Objective: To investigate the relationship of creatine phosphokinase a nd its isoenzymes with fetal asphyxia and risk at birth. Methods: Thir ty-five pregnant women with high-risk pregnancy were studied. Results: In 21 patients, fetal distress was diagnosed by interpretation of the fetal heart rate tracing (FHR). The remaining 14 women, having normal fetal cardiotocography, were considered as the control group. Total C K and its isoenzymes activity was measured in cord sera and 24 h after birth in peripheral blood. Abnormal FHR patterns correlate well with elevated enzyme activities. Total CK and its isoenzymes (CK-MM, CK-MB, and CK-BB) exhibited higher values in asphyxiated infants as compared to normal neonates. Electrocardiographic ischemia occurred in seven n ewborns who had elevated CK-MB and CK-BB levels, both at birth and wit hin 24 h postpartum. Chromatographic study showed in normal neonates t hat the predominant isoenzyme was CK-MM, whereas CK-BB activity was ne gligible. In the newborns with abnormal FHR, CK-MB and CK-BB were incr eased with predominance of CK-MB. Conclusions: Antepartum fetal distre ss is associated with release of CK-BB, and particularly CK-MB; theref ore, these biochemical markers may indicate either brain or myocardial damage.