Umbilical cord serum creatine kinase BB in the diagnosis of brain damage in the newborn: problems in interpretation.

Abstract
Raised values of creatine kinase BB (CKBB) in umbilical cord serum were obtained with some normal babies and those with fetal distress. Further investigation showed that the umbilical artery and vein tissue contain high CKBB activity, indicating that some cord blood samples may not solely reflect CKBB liberated from the brain.