Von Economo's disease and postencephalitic parkinsonism responsive to carbidopa and levodopa.

Postencephalitic parkinsonism (PEP) is currently perceived as having a very close etiologic relationship with encephalitis lethargica (von Economo's disease [EL]), with PEP developing immediately after the acute phase of EL or at some time later. EL was classically described by von Economo and has somnolent-ophthalmoplegic, hyperkinetic, and amyostatic-akinetic forms. Previous cases have reported success with levodopa in PEP. We report a case with PEP showing success after administration of levodopa and carbidopa. This case would support the hypothesis that this syndrome effects dopamine neurotransmission.