Is the EEC helpful in diagnosing and monitoring lithium intoxication? A case report and review of the literature

Lithium is potentially toxic to the central nervous system. Clinical lithiu m neurotoxicity may appear at any time during therapy and may go unrecogniz ed. Failure to appreciate this fact leads to delays in diagnosis and treatm ent, placing the patient at risk of permanent neurological damage or death. In spite of a largely clinical diagnosis of lithium intoxication, the EEC; provides an objective criterion of intoxication. We report a case of lithi um intoxication with neurotoxic symptoms associated with marked EEC changes despite moderate lithium serum levels. In contrast to the interindividuall y varying EEC changes under uncomplicated lithium therapy, pathological EEC findings are the rule in the case of intoxication. Several reports evince a closer relationship between neurotoxic symptoms with EEG changes than wit h serum levels of lithium. This is of clinical interest with respect to int oxication under therapeutic lithium serum levels, since the EEG is the only examination indicating an intoxication. In patients with intoxication, the phenomenon of long-lasting EEC changes after discontinuation of lithium is discussed with respect to neuronal storing of lithium and persisting neuro logical disturbances.