Different distribution of demyelination in chronic inflammatory demyelinating polyneuropathy subtypes.

In demyelinating polyneuropathies, distribution patterns of demyelination reflect underlying pathogenesis. Median and ulnar nerve conduction studies were reviewed in 85 typical chronic inflammatory demyelinating polyneuropathy (CIDP) patients and 29 multifocal acquired demyelinating sensory and motor neuropathy (MADSAM). Distal latencies were prolonged in typical CIDP and near normal in MADSAM. Abnormal amplitude reductions in the nerve trunks were more frequent in MADSAM than typical CIDP. Presumably because the blood-nerve barrier is anatomically deficient at the distal nerve terminals, antibody-mediated demyelination is a major pathophysiology in typical CIDP. In contrast, blood-nerve barrier breakdown is likely to be predominant in MADSAM. Unlabelled Image • A total of 136 CIDP patients was included and classified, based on clinical subtypes. • The distribution pattern of demyelination in each subtype was investigated. • Demyelination patterns were different and may reflect underlying pathophysiology. [ABSTRACT FROM AUTHOR]