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Test Code IGM or LAB72 Immunoglobulin M (IgM), Serum or Plasma

Specimen Requirements

Container Type:

Optimal: Gold or Mint*

*For STAT requests

Acceptable: Red or Green

Optimal Collection Volume: 

4.5mL; full tube

Minimum Volume:

1 mL whole blood

Collection Instructions:

Gently invert the sample 5-6 times after collection.

Specimen Transport:

Refrigerate

Processing Instructions: 

1. If serum, allow the specimen to clot for 30 minutes.

2. Centrifuge specimen within 2 hours of collection.

3. After centrifugation, specimen tubes without a gel barrier should have the serum or plasma aliquoted to a false bottom container.

4. Keep serum or plasma refrigerated until testing can be performed.

Specimen Stability

Specimen Type Temperature Time
Serum* Refrigerated 4 months
Room Temperature 2 months
Frozen 6 months

*Note: Heparinized plasma in gel separator tubes is less stable than serum and is only suitable for add-on testing up to 2 days following sample collection.

Specimen Rejection Criteria

Hemolysis Mild OK; Moderate OK; Gross Reject
Lipemia Mild OK; Moderate OK; Gross Reject
Icterus Mild OK; Moderate OK; Gross Reject
Other Quantity not sufficient

Useful For

Detecting and monitoring IgM-related disorders

Methodology

Roche Cobas - Immunoturbidimetric assay

Reference Ranges

Age Reference Range (mg/dL)
Adults 53-334
Newborns 6-25
1-6 months 19-103
7-12 months 32-132
1-3 years 41-190
4-5 years 41-186
6-8 years 46-197
9-10 years 49-230

Interpretive

Increased serum immunoglobulin concentrations occur due to polyclonal or oligoclonal immunoglobulin proliferation in hepatic disease (eg, hepatitis, liver cirrhosis), connective tissue diseases, acute and chronic infections, as well as in the cord blood of neonates with intrauterine and perinatal infections.

 

Elevation of IgM may occur in monoclonal gammopathies such as macroglobulinemia, primary systemic amyloidosis, monoclonal gammopathy of undetermined significance, and related disorders.

 

Decreased levels are found in patients with primary or secondary immune deficiencies.

 

Source: Mayo Medical Labs

Day(s) Performed

24/7

Expected TAT

Same day

Performing Laboratory

Bronson Laboratory, Chemistry - Kalamazoo

Sample Retention Time

7 days

CPT Code

82784

LOINC Code

2472-9