Chronic inflammatory demyelinating polyneuropathy

Abstract Chronic inflammatory demyelinating polyneuropathy (CIDP) is the commonest treatable neuropathy in the western world. Untreated it may result in severe disability but if diagnosed and treated early there is effective treatment for the majority of patients. Typical CIDP is readily recognised but the diagnosis of other subgroups can be more challenging. The pathology of polyradiculoneuropathies such as CIDP characteristically affects the most proximal regions of the peripheral nervous system, nerve roots and major plexuses. It is important to test these regions with electrodiagnostic studies since routine neurophysiology may not encounter regions of pathology. Although accepted as an autoimmune disorder with an underlying immunopathology involving T cell and B cell responses, there is no agreement on major target antigens; however recent studies have highlighted a role for molecules in non compact myelin which play an essential role in the formation and maintenance of the nodal structures and hence in the function of ion channels central to saltatory conduction. Controlled trials have proven the efficacy of corticosteroid, intravenous immunoglobulin and plasma exchange in the short term and intravenous immunoglobulin also in the long term. Immunosuppressive agents are widely used but their efficacy has not been proven in controlled trials. Recent trials have shown the importance of attempting treatment withdrawal in patients apparently in remission to conserve treatments that are very expensive and in short supply, since a significant proportion of patients may enter long lasting remission following short term therapy. For the relatively small group of patients who do not respond to these first line therapies new agents including monoclonal antibodies may have a role.