66 - Autoimmune peripheral neuropathies

Abstract

Abstract Autoimmune peripheral neuropathies (APNs) occur when immunological tolerance to peripheral nerve components (myelin, axon, or ganglionic neurons) is lost. The most common APNs are acute inflammatory polyneuropathies, such as Guillain-Barre syndrome (GBS), chronic inflammatory demyelinating polyneuropathy (CIDP), multifocal motor neuropathy (MMN), immunoglobulin M (IgM)–anti–myelin-associated glycoprotein (MAG) antibody–mediated paraproteinemic neuropathy, and those caused by vasculitis or viral infections. Both cellular and humoral factors, either independently or in concert with each other, appear to play a role, but the specific immune mechanisms have not been fully elucidated. Infectious agents, such as Campylobacter jejuni or even Zika virus, via molecular mimicry, are implicated in some GBS subtypes, but the factors that break tolerance in the other APNs remain unknown. In some acute or chronic APN, antibodies against peripheral nerve glycolipids or glycoproteins are pathogenic and well characterized. Newly identified antibodies against antigens at the nodes of Ranvier that cause conduction block define distinct CIDP subtypes and may best explain the acute worsening or rapid recovery after immunotherapy, as seen in CIDP and MMN. The current immunotherapies in all APNs are described based on controlled trials or clinical experience.