Progressive multifocal leukoencephalopathy

Alternative names:

P.M.L.

Definition:

A rare disorder involving advancing inflammation that occurs at multiple locations in the white matter of the brain. It tends to be a virus-induced disease seen in an immunocompromised host.

Symptoms and signs include loss of coordination, clumsiness, recent and progressively worsening weakness of one extremity (legs, most commonly). Other signs may include loss of language capability (aphasia), visual field defects, and headaches. The greatest risk is being immunosuppressed.