title: Anti-sulfatide IgM antibodies in peripheral neuropathy: to test or not to test?
abstract: OBJECTIVE
  Anti-sulfatide immunoglobulin M (IgM) antibodies have been associated with different forms of neuropathies but their diagnostic role in neuropathy remains unclear.
  
  
  METHODS
  The clinical association of increased titers of anti-sulfatide IgM antibodies in 570 patients with neuropathy and related disorders examined in our laboratory since 2004 was reviewed. Sera were tested by enzyme-linked immunosorbent assay at the initial serum dilution of 1:32,000 and titrated by serial two-fold dilution. In all positive patients IgM antibodies to myelin-associated glycoprotein (MAG) were also measured by western blot.
  
  
  RESULTS
  High titers of anti-sulfatide antibodies were found in 39 patients including 33 (85%) who also had anti-MAG IgM. Six patients did not have anti-MAG IgM including five in whom moderately increased anti-sulfatide titers were associated with different forms of neuropathy. One patient with a demyelinating neuropathy and IgM monoclonal gammopathy had markedly increased anti-sulfatide titers (1:256,000).
  
  
  CONCLUSIONS
  Increased titers of anti-sulfatide IgM antibodies are not infrequent in patients with neuropathy where they are often associated with a concomitant reactivity to MAG. A selective reactivity to sulfatide, however, is rarely found and is associated with different forms of neuropathy limiting its usefulness in the diagnosis of neuropathy.
authors.affiliation: Second Neurology, Humanitas Clinical and Research Centre, Department of Medical Biotechnology and Translational Medicine, Milan University, Rozzano, Milan, Italy.
authors.forename: C
authors.initials: C
authors.lastname: Giannotta
authors.forename: D
authors.initials: D
authors.lastname: Di Pietro
authors.forename: F
authors.initials: F
authors.lastname: Gallia
authors.forename: E
authors.initials: E
authors.lastname: Nobile-Orazio
mesh_terms: D000368:Aged; D000906:Antibodies / Q000097:blood*; D005260:Female; D006801:Humans; D007075:Immunoglobulin M / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D018992:Myelin-Associated Glycoprotein / Q000276:immunology; D010523:Peripheral Nervous System Diseases / Q000276:immunology*; D013433:Sulfoglycosphingolipids / Q000276:immunology*
chemical_list: D000906:Antibodies; D007075:Immunoglobulin M; D018992:Myelin-Associated Glycoprotein; D013433:Sulfoglycosphingolipids
keywords: IgM; antibodies; autoimmunity; neuropathy; sulfatide