2018 Volume 35 Issue 3 Pages 237-242
Peripheral neuropathy is caused by a variety of diseases. Early diagnosis and initiation of treatment is important because irreversible damage may occur. Although careful assessment of the mode of progression, symptoms and signs, blood and cerebrospinal fluid examinations, and electrophysiological studies may lead to diagnosis, nerve biopsy is also useful to determine the underlying diseases in some of the patients with neuropathy. Representative neuropathies are Guillain–Barré syndrome (GBS) and chronic inflammatory demyelinating polyneuropathy (CIDP). The degradation of the myelin sheath by macrophages has been reported in demyelinating form of GBS (i.e., acute inflammatory demyelinating polyneuropathy) and CIDP, and been considered to play an important role in the pathogenesis of these diseases. By contrast, recent studies suggested the association of autoantibodies directed against paranodal junctional proteins, such as anti–neurofascin 155 and anti–contactin 1 antibodies, to subpopulations of CIDP patients. Classical macrophage–induced demyelination is not observed in patients with these antibodies, whereas paranodal axo–glial dissection resulted from attachment of IgG4 antibodies to paranodal junctions plays a pivotal role in the mechanisms of neuropathy. Therefore, there are, at least, two distinct mechanisms that lead to nerve conduction abnormalities from pathological viewpoint. Physicians should take the variability of clinical and pathological findings of neuropathy.
