[Progressive multifocal leukoencephalopathy confirmed by PCR for JC virus in cerebrospinal fluid: case report].

A case of progressive multifocal leukoencephalopathy (PML) is presented, with literature review. PML diagnosis and its differential diagnosis are presented, with emphasis on neuroradiology, cerebrospinal fluid analysis and polymerase chain reaction studies. The prognosis of PML is usually poor, with a median survival of 1-6 months.