Neuropathologic correlates of persistent neurologic deficit in lithium intoxication.

While acute neurological symptoms complicating lithium therapy are well recognized, persistent neurologic dysfunction is uncommon. Regardless of the duration of symptoms, neuropathological correlates of lithium toxicity are few. We report the case of a 67-year-old man who developed lithium toxicity manifested by encephalopathy and coma followed by persistent dysarthria and ataxia. Autopsy revealed neuronal loss and gliosis in the cerebellar cortex and dentate nuclei; the cerebellar white matter exhibited prominent spongy change. Persistent cerebellar syndrome may occur with lithium intoxication and should be considered in the differential diagnosis of chronic cerebellar dysfunction.