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Isolation of Brain-infiltrating Leukocytes
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Published on: June 13, 2011

Progressive multifocal leukoencephalopathy in an immunocompetent patient

Panos G Christakis1, Daniel Okin, Anita J Huttner

  • 1Yale School of Medicine, New Haven, Connecticut, United States.

Journal of the Neurological Sciences
|February 5, 2013
PubMed

Insights

Progressive multifocal leukoencephalopathy (PML) is rare in immunocompetent individuals. This case highlights a potential treatment approach using serotonin receptor targeting therapy, showing promising results in stabilizing the patient's condition.

Area of Science:

  • Neuroimmunology
  • Viral Neurology

Background:

  • Progressive multifocal leukoencephalopathy (PML) is a rare demyelinating disease of the central nervous system.
  • PML is typically associated with profound cellular immunodeficiency.
  • JC virus (JCV) is the causative agent of PML.

Observation:

  • A 69-year-old immunocompetent male presented with subacute confusion, anxiety, and gait disturbance.
  • Brain MRI showed extensive white matter abnormalities in the parieto-occipito-temporal regions.
  • Cerebrospinal fluid (CSF) PCR confirmed JCV positivity, leading to a diagnosis of PML.

Findings:

  • Despite being immunocompetent, the patient's PML diagnosis was confirmed via biopsy.
  • Initiation of mirtazapine and mefloquine led to a 100-fold decrease in JCV DNA titre within six months.
  • Clinical stabilization and neuroimaging improvement were observed one year post-treatment.

Implications:

  • This case suggests PML can occur in immunocompetent individuals, challenging typical etiological assumptions.
  • Serotonin receptor targeting therapy (mirtazapine) may represent a novel therapeutic strategy for PML.
  • Further research is warranted to explore the efficacy of pharmacological interventions in PML management.

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