Neuron-specific enolase and myelin basic protein: relationship of cerebrospinal fluid concentrations to the neurologic condition of asphyxiated full-term infants

Neuron-specific enolase (NSE) and myelin basic protein (MBP) levels in the cerebrospinal fluid during the first 72 hours of life may predict the extent of brain damage in oxygen-deficient infants. Enolase is an enzyme involved in the metabolism of glucose. Myelin is a protein-lipid complex that forms a protective sheath around nerve fibers. Of 69 infants evaluated, 49 had some brain damage. NSE and MBP concentrations were associated with the degree of brain damage. Infants who had brain damage had the highest levels of both NSE and MBP. Infants who died or developed cerebral palsy at one year had significantly higher NSE and MBP levels at both 12 and 72 hours after birth than did infants who remained healthy or had only minor motor impairment. NSE concentrations measured at 12 hours were more accurate predictors of health outcome than MBP levels measured at either 12 or 72 hours.
Objective. We questioned whether neuron-specific enolase (NSE) and myelin basic protein (MBP) concentrations in cerebrospinal fluid (CSF) in the first 72 hours of life are correlated with the neurologic condition of asphyxiated full-term infants in the neonatal period and at 1 year of age. Patients and methods. Sixty-nine asphyxiated infants were studied with serial neurologic examination, cranial ultrasonography, and neurologic follow-up. CSF samples were obtained by lumbar puncture at 12 and 72 hours of life. NSE was measured by enzyme immunoassay, and MBP was measured by radioimmunoassay. Results. Twenty infants had no neonatal encephalopathy and 49 exhibited different stages of encephalopathy. NSE and MBP concentrations in CSF at 12 and 72 hours of life were related to the degree of neonatal encephalopathy. Neither NSE nor MBP levels were correlated with any perinatal factors. Infants with documented brain injury had the highest concentrations of both NSE and MBP. The concentrations of these two biochemical markers at both 12 and 72 hours correlated with adverse outcome (death or cerebral palsy at 1 year). Based on a receiver operating characteristics curve analysis for any given specificity, NSE at 12 hours was a more accurate marker than MBP at either 12 or 72 hours for distinguishing infants with motor impairment at age 1 year from infants with normal outcome at the same age. Conclusions. Our findings suggest that NSE and MBP are reliable biochemical markers for early estimates of hypoxic-ischemic brain damage in asphyctic full-term newborns, NSE being superior to MBP. Pediatrics 1994;93:234-240; neuron-specific enolase, myelin basic protein, hypoxic-ischemic encephalopathy, asphyxia, neonatal brain injury.