Treatment of multifocal motor neuropathy with intravenous immunoglobulin.

Multifocal motor neuropathy (MMN) is a rare inflammatory, chronically progressive, unremitting disorder affecting the peripheral nervous system. Although the etiology of this condition is not known, high titers of IgM Ab to GM1 may serve as a biomarker for this disease. Clinical findings of motor weakness are associated with focal conduction blocks and with time, axonal destruction. Evidence supporting an immune etiology as well as the use of intravenous immunoglobulin to limit the disease progression is reviewed.