Trace elements in whole blood of multiple sclerosis.

Fe, Zn, and Cu were determined by atomic absorption spectrometry in samples of whole blood after weighing and wet ashing with HNO3. 35 healthy persons were compared with 119 multiple sclerosis (MS) patients and 13 patients with other diseases of the CNS. The values from normal persons are in full agreement with those cited in the literature, men showing a significantly higher level of Fe than women, whereas for Zn and Cu there is no significant sex difference. In comparison with the reference group the patients show no difference at all for Fe and only a minor one for Cu, but Zn values are greatly increased in MS patients (by 25-75%). The increase is higher in the relapsing form of MS than in the chronic form, suggesting some connection with the activity of the disease. On the other hand, the duration of the illness and (implicitly) the age of the patient seem to be unimportant. As patients with other diseases of the CNS show a similar though somewhat smaller increase, we conclude that Zn elevation in whole blood is not a feature specific for MS. From the present results, however, we cannot decide if such deviations are causally connected with affections of the CNS or if they are only a concomitant manifestation.