Clinical and neuropathological aspects of long-term damage to the central nervous system after lithium medication

A female patient, who died at the age of 61 and had suffered from several manic-depressive psychoses for more than 30 years, developed three phases of intoxication under lithium therapy. There was a 15-year history of electro- and Pentetrazol-induced convulsive therapy prior to lithium medication; neuroleptics were still administered during lithium therapy. The last lithium intoxication, 3 years prior to death was during a low-dosage therapy with normal lithium levels followed by severe lasting impairment: akinesia, rigidity, dysarthria, ataxia, and an organic alteration in character. For the first time, neuropathological findings could be established in such a case: extensive damage to granule and Purkinje cells in the cerebellum; gliosis in the dentate nucleus, the inferior olives, and the nucleus ruber; cytoplasmic inclusions in various nerve cells of the cranial nerve nuclei; cytoplasmic vacuoles, especially in the cells of the supra-optic nucleus. Surprisingly little damage could be found in the substantia nigra and in the neostriatum. The clinical course as well as the pattern and intensity of the brain damage oppose an interpretation as a consequence of preceding convulsive shock therapy.