Specimen:

Serum

Collection Medium:

Minimum:

Pediatrics: 0.25 ml
Adults:  1 ml (absolute minimum:  0.5 ml)
  If MAG Ab is ordered on the same patient, submit two 1 ml aliquots.

Rejection Criteria:

Ambient and refrigerated specimens. Plasma and other body fluids. 
Heat-inactivated, severely lipemic, contaminated, or hemolyzed 
specimens.

Delivery Instructions:

Deliver to laboratory immediately after collection.  Critical frozen.

Analytic Time:

1 week

Reference Range:

Ganglioside (asialo-GM1) Antibody, IgG/IgM
  29 IV or less: Negative
  30-50 IV: Weak Positive
  51-150 IV: Positive
  151 IV or greater: Strong Positive

Ganglioside (GM1) Antibody, IgG/IgM
  29 IV or less: Negative
  30 IV-50 IV: Weak Positive
  51 IV-150 IV: Positive
  151 IV or greater: Strong Positive

Ganglioside (GM2) Antibody, IgG/IgM
  29 IV or less: Negative
  30 IV-50 IV: Weak Positive
  51 IV-150 IV: Positive
  151 IV or greater: Strong Positive

Ganglioside (GD1a) Antibody, IgG/IgM
  29 IV or less: Negative
  30 IV-50 IV: Weak Positive
  51 IV-150 IV: Positive
  151 IV or greater: Strong Positive

Ganglioside (GD1b) Antibody, IgG/IgM
  29 IV or less: Negative
  30 IV-50 IV: Weak Positive
  51 IV-150 IV: Positive
  151 IV or greater: Strong Positive

Ganglioside (GQ1b) Antibody, IgG/IgM
  29 IV or less: Negative
  30 IV-50 IV: Weak Positive
  51 IV-150 IV: Positive
  151 IV or greater: Strong Positive

Interpretive Data:

Ganglioside antibodies are associated with diverse peripheral 
neuropathies. Elevated antibody levels to ganglioside-monosialic acid 
(GM1) and the neutral glycolipid, asialo-GM1 are associated with motor 
or sensorimotor neuropathies, particularly multifocal motor neuropathy. 
Anti-GM1 may occur as IgM (polyclonal or monoclonal) or IgG antibodies. 
These antibodies may also be found in patients with diverse connective 
tissue diseases

as well as normal individuals. GD1a antibodies are associated with 
different variants of Guillain-Barré syndrome (GBS) particularly acute 
motor axonal neuropathy while GD1b antibodies are predominantly found 
in sensory ataxic neuropathy syndrome. Anti-GQ1b antibodies are seen in 
more than 80% of

patients with Miller-Fisher syndrome and may be elevated in GBS 
patients with ophthalmoplegia. The role of isolated anti-GM2 antibodies 
is unknown. These tests by themselves are not diagnostic and should be 
used in conjunction with other clinical parameters to confirm disease.

Methodology:

Enzyme-Linked Immunosorbent Assay (ELISA)

CPT Code:

83516 (x6)