Context (archaeology)

Biology

Gammopathy

Myelin-associated glycoprotein

Paleontology

Immunology

Monoclonal antibody

Immunoglobulin G

Central nervous system

Internal medicine

Myelin

Monoclonal

Medicine

Monoclonal gammopathy of undetermined significance

Immunohistochemistry

Immunoglobulin M

Antibody

Monoclonal gammopathy

Pathology

Scientific Reports

Antibodies against myelin-associated glycoprotein (MAG) almost invariably appear in the context of an IgM monoclonal gammopathy associated neuropathy. Very few cases of anti-MAG neuropathy lacking IgM-monoclonal gammopathy have been reported. We investigated the presence of anti-MAG antibodies in 69 patients fulfilling diagnostic criteria for CIDP. Anti-MAG antibodies were tested by ELISA and confirmed by immunohistochemistry. We identified four (5.8%) anti-MAG positive patients without detectable IgM-monoclonal gammopathy. In two of them, IgM-monoclonal gammopathy was detected at 3 and 4-year follow-up coinciding with an increase in anti-MAG antibodies titers. In conclusion, anti-MAG antibody testing should be considered in chronic demyelinating neuropathies, even if IgM-monoclonal gammopathy is not detectable.

Clinical and laboratory features of anti-MAG neuropathy without monoclonal gammopathy