Progressive multifocal leukoencephalopathy (PML) is a rare disorder that damages the material (myelin) that covers and protects nerves in the white matter of the brain.
The JC virus (JCV) causes PML. By age 10, most people have been infected with this virus, but it hardly ever causes symptoms.
Anyone with a weakened immune system, however, are at greater risk of developing PML. Causes of a weakened immune system include:
AIDS (less common now because of better AIDS treatments)
- Certain medications used to treat multiple sclerosis, rheumatoid arthritis, and related conditions
- Leukemia and lymphoma
- Loss of coordination, clumsiness
- Loss of language ability (aphasia)
- Memory loss
- Vision problems
- Weakness of the legs and arms that gets worse
Tests may include:
PML is a life-threatening condition. Talk to your doctor about care decisions.
In people with AIDS, treatment to strengthen the immune system can lead to recovery from the symptoms of PML. No other treatments have proved effective for PML.
Boren EJ, Cheema GS, et al. The emergence of progressive multifocal leukoencephaloparhy (PML) in rheumatic diseases. J Autoimmun. 2008;30(1-2):90-98.
Review Date: 2/6/2010
Reviewed By: David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine; Luc Jasmin, MD, PhD, Department of Neurosurgery at Cedars-Sinai Medical Center, Los Angeles, CA, and Department of Anatomy at UCSF, San Francisco, CA. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.
The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. © 1997- 2009 A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.