Electrodiagnosis of demyelinating neuropathies

The inflammatory demyelinating neuropathies constitute a significant propor tion of the acquired polyneuropathies. Major progress in finding the causes and in the treatment of these neuropathies has been made over the last dec ade. Early recognition is of paramount importance, because timely and appro priate treatment carl largely reduce morbidity and disability. Electrodiagn osis plays a key role in the detection and characterization of the inflamma tory demyelinating neuropathies. Electrodiagnostic criteria for primary dem yelination have therefore been developed They are empirically based on chan ges of nerve conduction parameters in populations of patients with a confir med clinical and laboratory diagnosis of inflammatory demyelinating neuropa thy. The challenge consists of defining criteria sets that are highly speci fic but also as sensitive as possible. Most of the hereditary demyelinating neuropathies are part of Charcot-Marie-Tooth disease type 1. The pattern o f nerve conduction abnormalities usually provides valuable clues for the di stinction from chronic inflammatory demyelinating neuropathies.