Sorted By Test Name - Mayo Medical Laboratories

GM1B
83189
Ganglioside Antibody Panel, Serum
Clinical Information: Peripheral neuropathies are a group of disorders that results from lesions on
peripheral nerves. Patients with a peripheral neuropathy can have symptoms of weakness, sensory loss,
and/or autonomic dysfunction. The causes of acquired peripheral neuropathies are varied, and include
vitamin deficiencies, metabolic abnormalities, infections, malignancies (paraneoplastic disorders), and
autoimmune diseases. A subset of the autoimmune-mediated peripheral neuropathies is associated with
the presence of circulating autoantibodies that bind to specific gangliosides. Gangliosides are
glycosphingolipids that contain sialic acid residues. Although present in the plasma membranes of many
cell types, gangliosides are particularly abundant in neural tissue. Guillain-Barre syndrome is one class of
autoimmune peripheral neuropathies, and comprises a spectrum of disorders including acute inflammatory
demyelinating polyradiculoneuropathy, acute motor axonal neuropathy, and acute motor and sensory
axonal neuropathy. This class of autoimmune neuropathies is generally characterized by an acute onset.
Although the diagnosis of these disorders is based significantly on clinical evaluation and
electrophysiologic studies, assessment of ganglioside antibodies, particularly against GM1, asialo GM1,
and GD1b, can provide useful information. It is thought that the Guillain-Barre syndrome disorders are
triggered by an infection, which results in production of infection-associated lipooligosaccharide-specific
antibodies. These antibodies subsequently bind to endogenous gangliosides, due to molecular mimicry,
which leads to immune-mediate damage to the peripheral nerves, ultimately resulting in the clinical
symptoms associated with the disorders.(1)
Useful For: Supporting diagnosis of neurological diseases-primarily motor neuron disease and motor
neuropathies
Interpretation: High titers (>1:2,000) have been found only in patients with multifocal motor
neuropathy and not with motor neuron disease. About 30% to 50% of patients with these clinical
syndromes or the pure motor variant of chronic inflammatory demyelinating polyneuropathy have
increased antibody titers. Increased antibody titers, therefore, appear to be a specific but not sensitive
marker of those related disorders. For IgG and IgM antibodies directed against monosialo GM1 and
disialo GD1b, 99% of 182 age- and sex-stratified normal individuals had titers 1:1,000
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