Plasma exchange in neurological diseases. A critical approach.

The rationale for and results of plasma exchange (PE) in the therapy of different immune-mediated neurological diseases such as myasthenia gravis, multiple sclerosis, acute and chronic-relapsing Guillain-Barré syndromes, polymyositis, dermatomyositis and amyotrophic lateral sclerosis are reviewed. Dialysis dementia and Refsum's disease, subacute sclerosing panencephalitis and schizophrenia are mentioned, too. If we exclude the treatment of acute Guillain-Barré syndrome, where PE alone appears to be sufficient to produce recovery or improvement, the combined use of immunosuppressive drugs and/or lymphocytapheresis is probably needed in the treatment of the other diseases. PE allows the disease to be controlled rapidly while long-term pharmacological control is established. An underlying theme in this review is the need of adequately controlled studies or at least of large case lists with exhaustive reports concerning both positive and negative results since a new perspective is needed for this topic. Nonetheless, a number of uncontrolled observations suggest that probably PE effectiveness in most immune-mediated neurological diseases could be proven if the requisite trials were performed.