The Role of Neuron-Specific Enolase (NSE) as a Biomarker in Perinatal Central Nervous System Injury in Small-for-Gestational-Age Newborns

Perinatal central nervous system injury is a significant source of morbidity in the newborn population, especially among vulnerable groups such as small for gestational age newborns. Chronic intrauterine hypoxia related to growth restriction may make neurons vulnerable to injury during the birth and early postnatal adaptation process. Early diagnosis of neuronal damage is often difficult, as clinical signs can either be subtle or nonspecific. Biochemical markers have thus received growing interest as adjuvant diagnostic tools. This was a prospective comparative study to assess the diagnostic importance of neuron-specific enolase as a biomarker of perinatal CNS injury in small for gestational age babies. A total of 82 term newborns were recruited between 2024 and 2025, including 41 growth-restricted newborns and 41 appropriate for gestational age controls. Serum NSE levels were measured within the first 24 hrs of life and then on the fifth day. Clinical neurological evaluation and neurosonography were done in all participants. Small for gestational age newborns had significantly higher concentrations of NSE than controls. Elevated levels were related to poor Apgar scores and abnormal neurosonographic findings. In a subset of growth-restricted infants, NSE elevation was present on the fifth day of life, indicating protracted neuronal stress. Notably, increased NSE values were found even in some of the infants that did not have overt neurological symptoms. The results support the possible role of neuron-specific enolase as a sensitive adjunct biomarker for early detection of perinatal CNS injury in growth-restricted neonates. Incorporation of NSE assessment into neonatal monitoring may lead to better identification of the vulnerability of the neurons and timely intervention.