Progressive multifocal leukoencephalopathy (PML) is a rare disorder that damages the material (
Causes, incidence, and risk factors
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