Copper, zinc, magnesium, and calcium in plasma and cerebrospinal fluid of patients with neurological diseases.

We investigated whether information on concentrations of some trace-mental concentrations in blood plasma or cerebrospinal fluid, or both, could be of value in diagnosis or management of various neurological diseases, and whether concentrations in plasma could serve as a means of estimating the protein or metal concentrations in cerebropsinal fluid. Samples of both from 82 patients were analyzed for copper, zinc, magnesium, and calcium by atomic absorption spectrophotometry. Protein concentrations in cerebrospinal fluid were also determined. Metal and protein concentrations in plasma and in cerebrospinal fluid were not strongly enough correlated to permit the estimation of one from the other. However, the correlation coefficients between calcium in plasma and cerebrospinal fluid (r = 0.41), magnesium and protein in cerebrospinal fluid (r = 0.40), magnesium in plasma and calcium in cerebrospinal fluid (r = 0.36), and magnesium and calcium in cerebrospinal fluid (r = 0.66) were statistically significant (P less than .01). Patients with cerebral infarctions had abnormally high copper concentrations in their plasma and cerebrospinal fluid. The ratio of plasma copper to plasma zinc was also significantly higher in cases of cerebral infarction.