Detecting or monitoring of IgM monoclonal gammopathies and IgM-related immune deficiencies
Nephelometry
IgM (Immunoglobulin M)
IgM single test
IgM, Serum
Immune Competence
Serum
Collection Container/Tube:
Preferred: Serum gel
Acceptable: Red top
Submission Container/Tube: Plastic vial
Specimen Volume: 1 mL
Collection Instructions: Centrifuge and aliquot serum into a plastic vial.
If not ordering electronically, complete, print, and send a Gastroenterology and Hepatology Test Request (T728) with the specimen.
0.5 mL
Gross hemolysis | OK |
Gross lipemia | Reject |
Gross icterus | OK |
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Serum | Refrigerated (preferred) | 28 days | |
Frozen | 28 days | ||
Ambient | 14 days |
Detecting or monitoring of IgM monoclonal gammopathies and IgM-related immune deficiencies
The gamma globulin band as seen in conventional serum protein electrophoresis consists of 5 immunoglobulins. In normal serum, about 5% is IgM.
Elevations of IgM may be due to polyclonal immunoglobulin production. Monoclonal elevations of IgM occur in macroglobulinemia.
Monoclonal gammopathies of all types may lead to a spike in the gamma globulin zone seen on serum protein electrophoresis.
Decreased immunoglobulin levels are found in patients with congenital deficiencies.
0-<5 months: 26-122 mg/dL
5-<9 months: 32-132 mg/dL
9-<15 months: 40-143 mg/dL
15-<24 months: 46-152 mg/dL
2-<4 years: 37-184 mg/dL
4-<7 years: 37-224 mg/dL
7-<10 years: 38-251 mg/dL
10-<13 years: 41-255 mg/dL
13-<16 years: 45-244 mg/dL
16-<18 years: 49-201 mg/dL
> or =18 years: 37-286 mg/dL
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.
Electrophoresis is usually required to interpret an elevated immunoglobulin class as polyclonal versus monoclonal. Immunofixation is usually required to characterize a monoclonal protein.
If there is a discrete M-peak, the monoclonal protein can be monitored with quantitative immunoglobulins. If immunoglobulin quantitation is used to monitor the size of a monoclonal protein that is contained in a background of polyclonal immunoglobulins, changes in the immunoglobulin quantitation may reflect changes in the background immunoglobulins, and serum protein electrophoresis should therefore be used to monitor the monoclonal protein.
Results determined by assays using different manufacturers or methods may not be comparable.
1. Webster ADB: Laboratory Investigation of primary deficiency of the lymphoid system. In: Clinics in Immunology and Allergy. Vol 5. 3rd ed. WB Saunders Company, 1985, 447-468
2. Pinching AJ: Laboratory investigation of secondary immunodeficiency. In: Clinics in Immunology and Allergy. Vol 5. 3rd ed. WB Saunders Company, 1985, 469-490
3. Dispenzieri A, Gertz MA, Kyle RA: Distribution of diseases associated with moderate polyclonal gammopathy in patients seen at Mayo Clinic during 1991. Blood. 1997;90:353
4. Kyle RA, Greipp PR: The laboratory investigation of monoclonal gammopathies. Mayo Clin Proc. 1978 Nov;53(11):719-739
5.
6. Kyle RA: Detection of quantitation of monoclonal proteins. Clin Immunol Newsletter. 1990;10:84-86
7. Dietzen DJ, Willrich MAV: Amino acids, peptides, and proteins. In: Rifai N, Chiu RWK, Young I, Burnham CAD, eds. Tietz Textbook of Laboratory Medicine. 7th ed. Elsevier; 2023:chap 31
In this Siemens Nephelometer II method, the light scattered onto the antigen-antibody complexes is measured. The intensity of the measured scattered light is proportional to the amount of antigen-antibody complexes in the sample under certain conditions. If the antibody volume is kept constant, the signal behaves proportionally to the antigen volume.
A reference curve is generated by a standard with a known antigen content on which the scattered light signals of the samples can be evaluated and calculated as an antigen concentration. Antigen-antibody complexes are formed when a sample containing antigen and the corresponding antiserum are put into a cuvette. A light beam is generated with a light emitting diode ,which is transmitted through the cuvette. The light is scattered onto the immuno-complexes that are present. Antigen and antibody are mixed in the initial measurement, but no complex is formed yet. An antigen-antibody complex is formed in the final measurement.
The result is calculated by subtracting the value of the final measurement from the initial measurement. The distribution of intensity of the scattered light depends on the ratio of the particle size of the antigen-antibody complexes to the radiated wavelength.(Instruction manual: Siemens Nephelometer II. Siemens, Inc; V 3, 2008; Addendum to the Instruction Manual 2.3, 08/2017)
Monday through Friday
This test has been cleared, approved, or is exempt by the US Food and Drug Administration and is used per manufacturer's instructions. Performance characteristics were verified by Mayo Clinic in a manner consistent with CLIA requirements.
82784
Test Id | Test Order Name | Order LOINC Value |
---|---|---|
IGM | Immunoglobulin M (IgM), S | 2472-9 |
Result Id | Test Result Name |
Result LOINC Value
Applies only to results expressed in units of measure originally reported by the performing laboratory. These values do not apply to results that are converted to other units of measure.
|
---|---|---|
IGM | Immunoglobulin M (IgM), S | 2472-9 |