Heterogeneity of Polyneuropathy Associated with Anti-MAG Antibodies

J Immunol Res. 2015:2015:450391. doi: 10.1155/2015/450391. Epub 2015 May 6.

Abstract

Polyneuropathy associated with IgM monoclonal gammopathy and anti-myelin associated glycoprotein (MAG) antibodies is an immune-mediated demyelinating neuropathy. The pathophysiology of this condition is likely to involve anti-MAG antibody deposition on myelin sheaths of the peripheral nerves and it is supposed to be distinct from chronic inflammatory demyelinating neuropathy (CIDP), another immune-mediated demyelinating peripheral neuropathy. In this series, we have retrospectively reviewed clinical and laboratory findings from 60 patients with polyneuropathy, IgM gammopathy, and anti-MAG antibodies. We found that the clinical picture in these patients is highly variable suggesting a direct link between the monoclonal gammopathy and the neuropathy. Conversely, one-third of patients had a CIDP-like phenotype on electrodiagnostic testing and this was correlated with a low titer of anti-MAG antibodies and the absence of widening of myelin lamellae. Our data suggest that polyneuropathy associated with anti-MAG antibodies is less homogeneous than previously said and that the pathophysiology of the condition is likely to be heterogeneous as well with the self-antigen being MAG in most of the patients but possibly being another component of myelin in the others.

MeSH terms

  • Aged
  • Aged, 80 and over
  • Antibodies, Monoclonal / immunology*
  • Autoantibodies / immunology*
  • Female
  • Humans
  • Immunoglobulin M / immunology
  • Male
  • Middle Aged
  • Myelin Sheath / immunology
  • Myelin-Associated Glycoprotein / immunology*
  • Peripheral Nerves / immunology
  • Polyneuropathies / immunology*
  • Polyradiculoneuropathy, Chronic Inflammatory Demyelinating / immunology*
  • Retrospective Studies

Substances

  • Antibodies, Monoclonal
  • Autoantibodies
  • Immunoglobulin M
  • MAG protein, human
  • Myelin-Associated Glycoprotein