Progressive Multifocal Leukoencephalopathy

Excerpt

Progressive multifocal leukoencephalopathy (PML) is a neurological condition caused by the JC virus. PML is a demyelinating disease preferentially affecting the central nervous system. In most individuals, it remains a latent infection however, it is particularly virulent in patients with immunosuppressive conditions such as AIDS, post solid organ and bone marrow transplant recipients, malignancies, and chronic inflammatory conditions. It has also been known to cause disease in patients who receive antiretroviral therapy as therapy can incite immune reconstitution. These cases of PML are termed PML- IRIS. Certain monoclonal antibodies, specifically, natalizumab used in the treatment of multiple sclerosis can also cause PML. It is an important differential to be considered when assessing neurological symptoms in patients with these specific risk factors.