brain, spinal cord, and nerve disorders
Progressive Multifocal Leukoencephalopathy (PML)
Symptoms of PML
The JC virus appears to cause no symptoms until it is reactivated. Symptoms of progressive multifocal leukoencephalopathy may begin gradually and usually worsen progressively. They vary depending on which part of the brain is infected. The first symptoms may be clumsiness, weakness, or difficulty speaking or thinking. As the disorder progresses, many people develop dementia and become unable to speak. Vision may be affected. People with progressive multifocal leukoencephalopathy eventually become bedbound. Rarely, headaches and seizures occur, mainly in people with AIDS. Death is common within 1 to 9 months of when symptoms start, but a few people survive longer (about 2 years). People who develop progressive multifocal leukoencephalopathy while taking a drug that suppresses the immune system (such asnatalizumab) may recover once the drug is stopped. However, many continue to have problems related to the infection. 