UMEM Educational Pearls

Category: Neurology

Title: Progressive Multifocal Leukoencephalopathy (PML)

Keywords: pml, progressive multifocal leukoencephalopathy, HIV, AIDS, opportunistic infections, demyelinating diseases (PubMed Search)

Posted: 8/5/2009 by Aisha Liferidge, MD (Updated: 10/21/2021)
Click here to contact Aisha Liferidge, MD

  • Progressive Multifocal Leukoencephalopathy (PML) is a life-threatening demyelinating condition that results from the reactivation of the polyomavirus JC. It primarily affects the immunocompromised (most commonly individuals with CD4 counts of < 200).
  • Prior to the advent and widespread use of anti-retroviral therapy, 1 to 5% of those with AIDS developed PML.  HAART is now considered a mainstay of treatment, along with cessation of immunosupressant therapies.
  • PML lesions typically occur bilaterally in the peri-ventricular white matter portions of the brain and do not conform to specific cerebrovascular territories
  • Non-contrast CT and MRI may reveal PML lesions, but definitive diagnosis is made via brain biopsy
  • Symptoms of PML include subacute neurologic deficits such as:  mental status abnormality, gait ataxia, limb ataxia, hemiparesis, monoparesis, and visual abnormalities such as diplopia and hemianopia.  Seizure occurs in up to 18% of cases.