19. Postencephalitic Parkinsonism

  1. Dennis W. Dickson MD2 and
  2. Roy O. Weller MD, PhD, FRCPath3
  1. Kurt A. Jellinger

Published Online: 21 SEP 2011

DOI: 10.1002/9781444341256.ch19

Neurodegeneration: The Molecular Pathology of Dementia and Movement Disorders, Second Edition

Neurodegeneration: The Molecular Pathology of Dementia and Movement Disorders, Second Edition

How to Cite

Jellinger, K. A. (2011) Postencephalitic Parkinsonism, in Neurodegeneration: The Molecular Pathology of Dementia and Movement Disorders, Second Edition (eds D. W. Dickson and R. O. Weller), Wiley-Blackwell, Oxford, UK. doi: 10.1002/9781444341256.ch19

Editor Information

  1. 2

    Departments of Pathology (Neuropathology) and Neuroscience Mayo Clinic, Jacksonville, FL, USA

  2. 3

    Clinical Neurosciences, University of Southampton School of Medicine, Southampton General Hospital, Southampton, UK

Author Information

  1. Institute of Clinical Neurobiology, Medical University Vienna, Vienna, Austria

Publication History

  1. Published Online: 21 SEP 2011
  2. Published Print: 2 SEP 2011

ISBN Information

Print ISBN: 9781405196932

Online ISBN: 9781444341256

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Keywords:

  • astrocytes;
  • encephalitis lethargica;
  • multisytem degeneration;
  • oculogyric crisis;
  • postencephalitic parkinsonism;
  • tauopathy (3R/4R tau);
  • tuft-shaped neurofibrillary tangles

Summary

Postencephalitic parkinsonism is a progressive neurodegenerative disease with clinical features referable mainly to the extrapyramidal and oculomotor systems. It represents the most common (and only permanent) sequel of encephalitis lethargica and clinically may resemble idiopathic Parkinson's disease. Morphologically it is characterized by severe neuronal depletion and gliosis in many brainstem nuclei, in particular the substantia nigra, associated with widespread globose neurofibrillary tangles and tau-positive glial inclusions that are usually immunoreactive for both three- and four-repeat tau isoforms. Postencephalitic parkinsonism shares histopathological features with other tauopathies as a multisystem degeneration with tau-positive neurofibrillary tangles that have biochemical and ultrastructure features similar to Alzheimer's disease while α-synuclein and TDP-43 pathologies are absent. Postencephalitic parkinsonism differs both clinically and morphologically from both idiopathic Parkinson's disease and other tau-related movement disorders. There is no known genetic factor associated with postencephalitic parkinsonism and its etiopathogenesis is still unknown; despite its suggested relationship with EL, recent research has failed to identify a causative agent.