Progressive Multifocal Leukoencephalopathy (PML)

Neuroinfectious disease experts diagnose and treat PML, along with its causes.

Neuroinfectious disease experts diagnose and treat PML, along with its causes.

Progressive multifocal leukoencephalopathy, or PML, is a rare, life-threatening infectious disease of the brain. PML is caused by the reactivation of a common virus, polyomavirus JC, that infects and destroys parts of the brain.

Around 85 percent of adults have antibodies to JC virus, a virus typically contracted in childhood. Most people infected with JC virus never have a problem.

However, JC virus can be reactivated and cause PML in a small percentage of people who have this virus. This happens more frequently in people with compromised immune systems.

PML Symptoms

The symptoms of PML vary, depending on where the virus affects the brain and the extent of the damage. Some of the more frequent symptoms include the following:

  • A lack of control during movement of the voluntary muscles (ataxia), particularly in the limbs or when walking
  • Weakness on one half of the body (hemiparesis) or in one limb (monoparesis)
  • Vision changes, such as blindness in half of your field of vision (hemianopia) or double vision (diplopia)
  • Altered mental state

PML Risk Factors

  • Compromised immune system
  • Untreated AIDS
  • Use of monoclonal antibodies, particularly those used to treat multiple sclerosis (natalizumab) and lymphoma (rituximab)
  • Use of long-term immune-suppressing drugs, such as for organ transplants, rheumatoid arthritis, systemic lupus erythematosus and cancer

PML Treatment at Rush

PML Diagnosis

Neuroinfectious disease neurologists at Rush can diagnose whether you have PML. Your diagnostic testing may include the following:

  • Neurological exam
  • Magnetic resonance imaging (MRI)
  • Spinal tap or a brain biopsy to test for the JC virus in the cerebral spinal fluid

PML Treatment

At this time, there is not a treatment that directly targets the JC virus. All our treatments at Rush focus on rebuilding your immune system, as that can help your body clear the JC virus infection.

Your treatment will depend on why the JC virus became reactivated. For example, your plan may include the following:

  • Antiretroviral therapy if you have HIV and PML
  • Stopping the drug natalizumab if you have multiple sclerosis (MS) and PML and working with your MS provider to find another medication
  • Use of the drug filgrastim to restore your immune function

Rush Excellence in Progressive Multifocal Leukoencephalopathy

  • PML expertise: Neuroinfectious disease experts at Rush are skilled at diagnosing and treating PML. They also understand the long-term neurologic complications of any underlying conditions that lead to its development.
  • Coordinated care: PML typically occurs because of another condition, such as MS, cancer or HIV. Neuroinfectious disease providers work closely with cancer, infectious disease and other specialists at Rush so you have comprehensive care that takes each condition into consideration.
  • Nationally recognized care: Rush's neurology and neurosurgery program is consistently rated among the best in the country by U.S. News & World Report. That means you can rest assured that you are receiving high-quality, up-to-date care.
  • Clinical trials: As an academic health system, Rush offers ongoing research into newer, more effective treatments. This research includes clinical trials for PML and the conditions (such as MS, cancer and HIV) that can lead to its development.

Get a Second Opinion

A second opinion can confirm your PML diagnosis and point to new treatment options.

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Clinical Trials

Researchers at Rush are investigating new PML treatments.

See open clinical trials