Progressive multifocal leukoencephalopathy: failure of response to transfer factor and cytarabine

A 57-year-old woman with a 2-year history of neurologic symptoms was shown on brain biopsy to have progressive multifocal leukoencephalopathy. Although cell-mediated immune mechanisms were impaired, no underlying disease was found. The administration of transfer factor enhanced cell-mediated immunity, but the neurologic symptoms did not improve. Separate courses of glucocorticoids and cytarabine were associated with rapid neurologic deterioration.