Cerebrospinal fluid neuron-specific enolase in non-selected patients

The degree to which cerebrospinal fluid (CSF) neuron-specific enolase (NSE) contributes to the diagnosis and prognosis of disorders of the central nervous system (CNS) or peripheral nervous system (PNS) is still under debate. The aim of the study was thus to assess the validity of CSF-NSE levels in the diagnostic work-up of these conditions. The study consecutively included 106 adult patients who had undergone a diagnostic spinal tap or myelography during the diagnostic work-up for various CNS or PNS disorders. Thirty-five of these patients (16 F, 19 M, aged 24-88 years) without indication of a CNS disorder and with normal routine CSF investigations served as controls. The remaining 71 patients (31 F, 40 M, aged 28-87 years) constituted the disease group. CSF-NSE was independent of sex and age. The upper reference limit of CSF-NSE was 0.01536 ng/L. CSF-NSE was elevated in 13 of the 71 patients (18%): 6 with metabolic myopathy, 4 with polyneuropathy and 3 with hepatic encephalopathy, multiple sclerosis and paraspasticity, respectively. Only 6 of the 13 patients (46%) showed CNS involvement. The study shows that CSF-NSE is elevated in only one-fifth of unselected patients who consecutively undergo a spinal tap. CSF-NSE is elevated most frequently in patients with metabolic myopathy and polyneuropathy, even in cases without CNS abnormalities.