Phase III Randomized, Double-Blind, Sham-Controlled Study of Plasma Exchange for Acute Severe Attacks of Inflammatory Demyelinating Disease Refractory to Intravenous Methylprednisolone

PROTOCOL ENTRY CRITERIA: --Disease Characteristics-- Idiopathic inflammatory demyelinating syndrome, as follows: biopsy-proven if necessary - established diagnosis of multiple sclerosis (MS) using Poser criteria; acute disseminated encephalomyelitis; Marburg's variant of MS Balo's concentric sclerosis Eligible without biopsy: acute transverse myelitis; Devic's syndrome Acute neurologic deficit markedly affecting consciousness, language, or brainstem/spinal cord function, i.e., aphasia, paraplegia, coma, quadriplegia, hemiplegia, severe organic brain syndrome Deficit unresponsive to 5 days of high-dose intravenous methylprednisolone (MePRDL), as follows: deficit duration of 21 days to 3 months AND no improvement 14 days after beginning MePRDL OR deficit duration of 12 to 20 days AND continued deterioration after completion of MePRDL No chronically progressive demyelinating disease No HIV-associated demyelinating syndrome No progressive multifocal leukoencephalopathy No optic neuritis --Prior/Concurrent Therapy-- No more than 3 months of prior steroid therapy Failure on prior MePRDL required Minimum dose 7 mg/kg per day for 5 days At least 6 weeks since other immunosuppressives, e.g., cyclophosphamide, azathioprine, cyclosporine --Patient Characteristics-- Renal: Creatinine less than 1.5 mg/dL Cardiovascular: No hypovolemia; no infarction; no vasculitis; no other major systemic cardiovascular illness Pulmonary: No major respiratory illness Other: No infection, including hepatitis or human immunodeficiency virus; no recent intravenous drug abuse; no high-risk sexual behavior; no cardiac, cerebrovascular, or autonomic dysfunction that would increase risk of hypotension; no other major systemic illness that would preclude protocol therapy; no pregnant or nursing women; negative serum pregnancy test required of fertile women; effective contraception required