Progressive multifocal leukoencephalopathy Health Article

Definition

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.

Alternative Names

PML

Causes, incidence, and risk factors

The JC virus (JCV) causes PML. This virus is found in a lot of people, but usually does not cause symptoms. However, it triggers PML in people who have poor immune function (immunocompromised).

The disease occurs in 4% of adults with AIDS.

Symptoms

• Headaches
• Loss of coordination, clumsiness
• Loss of language ability (aphasia)
• Memory loss
• Vision problems
• Weakness of the legs and arms that gets worse

Signs and tests

Tests may include:

• Cytology exam of the urine
• CT scan
• Electroencephalogram (EEG)
• MRI

Treatment

Treatment consists of antiviral drugs and other medications.

Expectations (prognosis)

PML is a very serious condition. Talk to your doctor about care decisions.

References

Mandell GL, Bennett JE, Dolin R. Principles and Practice of Infectious Diseases. 5th ed. London: Churchill Livingstone; 2000:1856-1861.

Cohen J, Powderly WG. Infectious Diseases. 2nd ed. New York, NY: Elsevier; 2004:2046.