Plasma and cerebrospinal fluid concentrations of magnesium in epileptic children.

In order to discriminate between conflicting reports in the literature, plasma and cerebrospinal fluid magnesium levels from epileptic children were compared with those of control children. To exclude the possibility of methodological artifacts, two methods for Mg determination were used: atomic absorption spectrophotometry and a colorimetric procedure. By both methods a significantly decreased concentration of Mg in plasma was found in epileptics. A positive correlation of the hypomagnesemia with the severity of epilepsy was found: the more severe the epilepsy, the lower was the plasma Mg. A significant increase of Mg concentration in CSF of epileptics was found. The most likely origin of Mg in CSF in epilepsy is the CNS tissue from which Mg is released. It is suggested that these alterations of Mg concentrations in plasma and CSF originate from a functional impairment of the cell membranes which might occur in epilepsy.