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Progressive multifocal leukoencephalopathy in a patient without apparent immunosuppression

Christos Vaklavas1, Elsa P Sotelo-Rafiq, Jordan Lovy

  • 1Department of Internal Medicine, The University of Texas Medical School at Houston, Houston, Texas, USA. Chris.Vaklavas@ccc.uab.edu

Virology Journal
|October 6, 2010
PubMed

Insights

This case study details a rare instance of progressive multifocal leukoencephalopathy (PML) in an elderly man without known immune compromise. Diagnosis was confirmed by brain biopsy and JC virus detection, despite initial negative tests.

Area of Science:

  • Neurology
  • Virology
  • Pathology

Background:

  • Progressive multifocal leukoencephalopathy (PML) is a rare, demyelinating disease affecting the brain's white matter.
  • PML is typically associated with severe immune deficiency, often caused by the John Cunningham (JC) virus.

Observation:

  • An 80-year-old man presented with dysphagia and left-sided weakness.
  • Initial MRI showed white matter abnormalities; CSF PCR for JC virus was negative.
  • Brain biopsy revealed foamy macrophages and positive staining for anti-simian virus 40 antibodies.

Findings:

  • Postoperative CSF PCR confirmed JC viral DNA, establishing the diagnosis of PML.
  • Extensive investigations failed to identify any underlying immunocompromising disorder.
  • The patient experienced rapid neurologic deterioration and died 3.5 months post-diagnosis.

Implications:

  • This case highlights the possibility of PML in elderly individuals without apparent immune compromise.
  • It underscores the diagnostic utility of brain biopsy when initial PCR tests are negative.
  • The findings prompt consideration of atypical presentations of PML and the need for thorough etiological investigation.

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