EEG with triphasic waves in Borrelia burgdorferi meningoencephalitis.

We describe a case of encephalopathy in which the clinical picture and triphasic waves in the EEG indicated a metabolic cause. However, the illness was caused by neuroborreliosis. The occurrence of triphasic waves in the EEG is a strong evidence of metabolic encephalopathy, but triphasic waves are not specific for metabolic encephalopathy. Triphasic waves have been described in a number of non-metabolic encephalopaties and structural brain lesions. To our knowledge, this is the first report of triphasic waves in Borrelia burgdorferi meningoencephalitis.