Progressive Multifocal Leukoencephalopathy
by Cynthia M. Johnson, MA
Progressive Multifocal Leukoencephalopathy (PML) is a rare disease that gets worse over time. It harms brain cells.
PML is caused by an infection by a specific virus. Many people get this virus as a child, but do not get sick until later. It stays in the body and does not cause problems in most.
If the immune system becomes weak, the virus can start to cause problems. It attacks the coating around the brain cells. Messages can't be passed between cells without this coating.
Risk Factors TOP
PML is most common in people who have problems with their immune system. These problems may be from:
You will feel worse over time. You may have:
Your doctor will ask about your symptoms and health history. A physical exam will be done.
An MRI scan will be needed to see any damage to the brain cells. This may help to rule out other causes.
To confirm PML, your doctor may need:
There is no way to treat the infection or PML. Treatment is aimed at ways to make your immune system better to stop further harm. It will depend on your health needs, but here are some methods:
Harm to the cells can't be fixed. This can cause severe disability.
You can’t prevent the virus that causes PML. Keep your immune system as healthy as you can. It may help prevent certain infections.
AIDS Information, Education, Action
NORD—National Organization for Rare Disorders
Canadian AIDS Society
CORD—Canadian Organization for Rare Disorders
Grebenciucova E, Pruitt A. Infections in patients receiving multiple sclerosis disease-modifying therapies. Curr Neurol Neurosci Rep. 2017;17(11):88.
NINDS progressive multifocal leukoencephalopathy information page. National Institute of Neurological Disorders and Stroke website. Available at https://www.ninds.nih.gov/Disorders/All-Disorders/Progressive-Multifocal-Leukoencephalopathy-Information-Page. Accessed June 25, 2018.
Progressive multifocal leukoencephalopathy. EBSCO DynaMed Plus website. Available at: http://www.dynamed.... Updated December 1, 2017. Accessed June 25, 2018.
Progressive multifocal leukoencephalopathy (PML). AETC National Resource Center website. Available at:
...(Click grey area to select URL)
Updated May 1, 2013. Accessed June 25, 2018.
Warnke C, Menge T, Hartung HP, et al. Natalizumab and progressive multifocal leukoencephalopathy: what are the causal factors and can it be avoided? Arch Neurol. 2010;67(8):923-930.
Last reviewed June 2018 by EBSCO Medical Review Board Rimas Lukas, MD
Last Updated: 6/25/2018
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