Category: Immunoglobulin/ Complement
Test Code: 402
Methodology: Nephelometry
Reference Range: Normal Range: Accompanies report (age dependent).
CPT Code: 83883
Schedule / Turnaround Time: Report availability is one week from the time of specimen receipt.
Specimen Requirements:

Specimen need not be refrigerated or frozen. Collect 2-3 ml of blood in a red top or serum separator tube. If possible, separate serum from clot and place into white tube provided with Immco Diagnostics’ collection kits. If separation facilities are not available, the blood can be sent in the tube used for collection.

Sample Stability:

Sample is stable at ambient temperature during shipment. If sample is stored prior to shipment, it is stable refrigerated (2-8˚C) up to five days and frozen (-20˚C or lower) up to one year.


IgM is the first class of immunoglobulin synthesized in response to particulate antigens. On active immunization, IgM rapidly appears in the serum, but levels normally drop after a week, usually in parallel with the increase in IgG. Elevated IgM levels are associated with hepatitis, myeloma, Waldenstrom’s macroglobulinanemia and other infections. Reduced levels can occur in antibody deficiency syndrome. Normal serum levels vary with age and race.