Does the historical literature on encephalitis lethargica support a simple (direct) relationship with postencephalitic Parkinsonism?

Joel A. Vilensky, Sid Gilman, Sherman McCall

Research output: Contribution to journalReview article

15 Scopus citations


This article and the subsequent one suggest that the currently accepted view of a simplistic (direct) relationship between encephalitis lethargica (EL) and postencephalitic Parkinsonism (PEP) is based on a incomplete evaluation of the epidemic period literature. In this article we provide a detailed analysis of the literature from the period that demonstrates that Parkinsonism was not initially part of acute EL symptomatology, that PEP was not typically the prevailing type of chronic EL and that oculogyric crises were never part of acute EL symptomatology and not initially associated with PEP. The second paper uses these finding, and also examines the clinical justifications for concluding that all patients with PEP had prior acute episodes of EL, to reevaluate the presumed direct etiologic relationship between EL and PEP.

Original languageEnglish (US)
Pages (from-to)1124-1130
Number of pages7
JournalMovement Disorders
Issue number9
StatePublished - Jul 15 2010



  • Encephalitic Parkinsonism
  • Epidemic encephalitis
  • Oculogyric crises
  • Von Economo's disease

ASJC Scopus subject areas

  • Clinical Neurology
  • Neurology
  • Medicine(all)

Cite this