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:

Heat-inactivated, severely lipemic, contaminated, or hemolyzed 
specimens.  Plasma and other body fluids. No ambient or refrigerated 
specimens.

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:

Elevated antibody levels to ganglioside-monosialic acid (GM1), a 
glycolipid, have been shown in some instances to be associated with 
certain neurological disorders such as: lower motor neuron syndrome, 
amyotrophic lateral sclerosis, multiple sclerosis, other multifocal 
neuropathies, and systemic lupus erythematosus (SLE) with central 
nervous system involvement.  Some normal individuals have low levels of 
GM1 antibodies.  GM2 and GD1a antibodies have been associated with 
Guillaino-Barrvariants, motor neuropathies and sensory demyelinating 
neuropathy while FD1b has been associated with sensory neuropathy.  
GQ1b has been associated with motor and sensorimotor neuropathies, 
Miller-Fisher syndrome and Bickerstaff's brainstem encephalitis. The 
cause of such disorders is not fully understood and, therefore, the 
significance of elevated antibody levels has not been adequately 
established.  The test has been designed to be an aid in the monitoring 
of changes in antibody levels before, during, and after treatment and 
may be helpful to the clinician in conjunction with other tests and 
clinical symptoms for the evaluation of treatment in these patients.

Methodology:

Enzyme-Linked Immunosorbent Assay (ELISA)

CPT Code:

83516 (x6)