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Published on: July 4, 2007

Inflammatory infratentorial progressive multifocal leukoencephalopathy in a patient with rheumatoid arthritis

Boleslaw Lach1, Barbara Connolly, Christian Wüthrich

  • 1Department of Pathology & Molecular Medicine, McMaster University, Hamilton Health Sciences, Hamilton General Hospital (Neuropathology), Hamilton, Ontario, Canada.

Neuropathology : Official Journal of the Japanese Society of Neuropathology
|May 21, 2013
PubMed

Insights

A patient with rheumatoid arthritis (RA) on methotrexate developed progressive multifocal leukoencephalopathy (PML) with unusual cerebellar and brainstem inflammation. Neuropathology confirmed JC virus in affected cells, highlighting an atypical presentation of this opportunistic infection.

Area of Science:

  • Neuroimmunology
  • Neuropathology
  • Infectious Diseases

Background:

  • Rheumatoid arthritis (RA) is a chronic autoimmune disease.
  • Methotrexate is a common immunosuppressive therapy for RA.
  • Progressive multifocal leukoencephalopathy (PML) is a rare, often fatal, demyelinating disease caused by the JC virus.

Observation:

  • An 84-year-old male RA patient on methotrexate presented with confusion and cerebellar dysfunction.
  • The patient's condition progressed over two months, leading to death.
  • Autopsy revealed neuropathological evidence of PML.

Findings:

  • PML lesions were predominantly located in the cerebellum and brainstem.
  • Immunohistochemistry showed significant infiltration of CD8+ T-cells and microglia in affected areas.
  • JC virus DNA was detected within oligodendrocytes and cerebellar granule cells.

Implications:

  • This case demonstrates an unusual inflammatory presentation of PML.
  • The findings suggest that methotrexate-associated immunosuppression may contribute to atypical PML localization.
  • Highlights the importance of considering opportunistic infections in immunocompromised patients with neurological symptoms.
Keywords:
cerebellar syndromedemyelinationmethotrexateprogressive multifocal leukoencephalopathyrheumatoid arthritis

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