Immune pathogenesis and treatment of multifocal motor neuropathy.

Multifocal motor neuropathy (MMN) is a rare, probably immune-mediated chronic disorder characterized by asymmetric distal limb weakness and conduction block. The exact pathogenesis of MMN is still unclear, but IgM anti-GM1 antibodies, which can be detected in sera from approximately half of all MMN patients, are thought to play an important role. Treatment with intravenous immunoglobulin (IVIG) is effective in the vast majority of patients, but, despite IVIG maintenance treatment, many patients experience a slowly progressive decline in muscle strength. In this review we will summarize the results from studies on pathogenesis. We will discuss current treatment strategies of MMN and how insight into MMN pathogenesis may translate into novel therapies in the future.