Pathology of CIDP

Abstract

Chronic inflammatory demyelinating polyneuropathy (CIDP) is a form of chronic neuropathy caused by heterogeneous immununological processes. In addition to the typical CIDP, several variants, such as distal, multifocal, focal, motor, and sensory CIDPs, have also been included as subtypes of CIDP. Demyelination caused by macrophages has been reported in CIDP and is considered to play an important role in the pathogenesis of this disease irrespective of subtypes. By contrast, recent studies have suggested the association of IgG4 antibodies directed against paranodal junction components, such as aneurofascin 155 and contactin 1, to subpopulations of typical and distal CIDP patients. Paranodal dissection resulting from the deposition of IgG4 at paranodal junctions and the absence of macrophage–induced demyelination are the characteristic pathological features in patients with these antibodies. Therefore, patients with these antibodies are now considered to have an independent disease entity, called as autoimmune nodopathy, because the mechanism leading to nerve conduction abnormalities is distinct from that in conventional CIDP patients with macrophage–induced demyelination.