Elevated S100B level in cerebrospinal fluid could predict poor outcome of carbon monoxide poisoning

Abstract Objective S100B is a calcium-binding protein produced by astroglia in the brain and has been used as a marker of neuronal damage after brain trauma. We investigated the utility of S100B in cerebrospinal fluid (CSF) measured during the early phase of carbon monoxide (CO) poisoning in predicting the subsequent clinical course. Methods The study included 31 patients who were admitted to the hospital with loss of consciousness following CO poisoning. S100B levels were measured by enzyme-linked immunosorbent assay in CSF, and serum samples collected simultaneously within 24 hours and on the fourth day after CO exposure. All patients were followed for at least 3 months and divided into 3 groups based on the clinical course: persistent vegetative state (PVS), delayed encephalopathy (DE), and complete recovery with no complications (NC). Results During the 3-month period, 3 patients developed PVS, 5 developed DE, and 23 were classified as NC. The mean S100B levels in the CSF within 24 hours after CO exposure were higher in the PVS group (9.25 ng/mL) than in the DE (2.03 ng/mL) and NC groups (1.86 ng/mL). However, the mean serum S100B levels were not elevated in the 3 groups (0.21, 0.59, and 0.16 ng/mL, respectively). Conclusion Early elevation of S100B in CSF after CO poisoning could be a suitable predictor of subsequent development of PVS.