Elevated cerebrospinal fluid lactic acid levels in Creutzfeldt-Jakob disease.

The concentration of cerebrospinal fluid (CSF) lactic acid was determined in three patients with biopsy proven Creutzfeldt-Jacob disease (CJD). When compared with twenty demented patients diagnosed as having either Alzheimer's disease or multi-infarct dementia, the CSF lactic acid values of the CJD patients were significantly elevated (p less than .001). Elevated CSF lactic acid levels may be an important biochemical marker of CJD and useful in the differential diagnosis of dementia.