Evaluation of serum markers of neuronal damage following severe hypoglycaemia in adults with insulin-treated diabetes mellitus

Background Neurone-specific enolase (NSE) and protein S-100 (S-100) may be used as markers of acute neuronal damage in humans with neurological disord ers. Method To evaluate their use following a single episode of severe hypoglyca emia (defined as an episode requiring external assistance to aid recovery), serum concentrations of NSE and S-100 were measured following hypoglycaemi a which had not caused persistent neurological impairment in 16 patients wi th insulin-treated diabetes (the 'hypo' subjects), and in three diabetic pa tients who died following severe hypoglycaemia. The serum proteins were als o measured in 10 subjects with insulin-treated diabetes who had not experie nced an episode of severe hypoglycaemia within the preceding year (the 'con trol' subjects). Results No differences in serum concentrations of NSE and S-100 were observ ed between the 'control' and the 'hypo' subjects at either 36 hours or seve n days after the episode of severe hypoglycaemia (p>0.05). However, in two of the three subjects who died following hypoglycaemia, serum concentration s of the markers were markedly elevated. Conclusions. Any neuronal injury occurring during severe hypoglycaemia that is not associated with persistent neurological deficit is insufficient to provoke elevation of these serum markers. However, the measurement of serum concentrations of NSE and S-100 may have a prognostic role in evaluating c linical outcome following severe hypoglycaemia which is associated with neu rological damage. Copyright (C) 1999 John Wiley & Sons, Ltd.