This article points out the differences in NSE levels in different clinical groups, such as patients after an incident of hypoxic/ischemic encephalopathy (HIE), neuroinfection, or particular inflammatory processes in the nervous system region, as well as central nervous system (CNS) injury, selected MD, neurodegenerative disorders (NGDs), headaches, or epilepsy (EP). The gene discussed is ENO2; the disease is epilepsy.