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 disorders. Method To evaluate their use following a single episode of severe hypoglycaemia (defined as an episode requiring external assistance to aid recovery), serum concentrations of NSE and S-100 were measured following hypoglycaemia which had not caused persistent neurological impairment in 16 patients with insulin-treated diabetes (the 'hypo' subjects), and in three diabetic patients who died following severe hypoglycaemia. The serum proteins were also measured in 10 subjects with insulin-treated diabetes who had not experienced an episode of severe hypoglycaemia within the preceding year (the 'control' subjects). Results No differences in serum concentrations of NSE and S-100 were observed between the 'control' and the 'hypo' subjects at either 36 hours or seven days after the episode of severe hypoglycaemia (p>0.05). However, in two of the three subjects who died following hypoglycaemia, serum concentrations 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 clinical outcome following severe hypoglycaemia which is associated with neurological damage. Copyright (C) 1999 John Wiley & Sons, Ltd.