Test Id : B2M
Beta-2-Microglobulin, Serum
Useful For
Suggests clinical disorders or settings where the test may be helpful
Prognosis assessment of multiple myeloma
Evaluation of renal tubular disorders
Testing Algorithm
Delineates situations when tests are added to the initial order. This includes reflex and additional tests.
For more information, see Multiple Myeloma: Laboratory Screening
Method Name
A short description of the method used to perform the test
Nephelometry
NY State Available
Indicates the status of NY State approval and if the test is orderable for NY State clients.
Reporting Name
Lists a shorter or abbreviated version of the Published Name for a test
Aliases
Lists additional common names for a test, as an aid in searching
B2 Microglobulin
B2M, Serum
Beta Microglobulin
Beta-2-Microglobulin
Microglobulin, Beta 2
Beta 2 Microglobulin
Testing Algorithm
Delineates situations when tests are added to the initial order. This includes reflex and additional tests.
For more information, see Multiple Myeloma: Laboratory Screening
Specimen Type
Describes the specimen type validated for testing
Serum
Specimen Required
Defines the optimal specimen required to perform the test and the preferred volume to complete testing
Supplies: Sarstedt Aliquot Tube 5 mL (T914)
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.
Special Instructions
Library of PDFs including pertinent information and forms related to the test
Forms
If not ordering electronically, complete, print, and send Renal Diagnostics Test Request (T830)
Specimen Minimum Volume
Defines the amount of sample necessary to provide a clinically relevant result as determined by the testing laboratory. The minimum volume is sufficient for one attempt at testing.
0.5 mL
Reject Due To
Identifies specimen types and conditions that may cause the specimen to be rejected
| Gross hemolysis | OK |
| Gross lipemia | OK |
| Gross icterus | OK |
Specimen Stability Information
Provides a description of the temperatures required to transport a specimen to the performing laboratory, alternate acceptable temperatures are also included
| Specimen Type | Temperature | Time | Special Container |
|---|---|---|---|
| Serum | Refrigerated (preferred) | 28 days | |
| Ambient | 14 days | ||
| Frozen | 28 days |
Useful For
Suggests clinical disorders or settings where the test may be helpful
Prognosis assessment of multiple myeloma
Evaluation of renal tubular disorders
Testing Algorithm
Delineates situations when tests are added to the initial order. This includes reflex and additional tests.
For more information, see Multiple Myeloma: Laboratory Screening
Clinical Information
Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test
Beta-2-microglobulin (beta-2-M) is a small membrane protein (11,800 Da) associated with the heavy chains of class I major histocompatibility complex proteins and is, therefore, on the surface of all nucleated cells. The small size allows beta-2-M to pass through the glomerular membrane, but it is almost completely reabsorbed in the proximal tubules.
Serum beta-2-M levels are elevated in diseases associated with increased cell turnover. Levels are also elevated in several benign conditions such as chronic inflammation, liver disease, kidney dysfunction, some acute viral infections, and a number of malignancies, especially hematologic malignancies associated with the B-lymphocyte lineage.
In multiple myeloma, beta-2-M is a powerful prognostic factor, and values less than 4 mcg/mL are considered a good prognostic factor.
In renal tubular disease, serum levels are low and urine levels are high. Although urine beta-2-M has been used to assess tubular dysfunction, it is not stable in urine below pH 5.5.
Reference Values
Describes reference intervals and additional information for interpretation of test results. May include intervals based on age and sex when appropriate. Intervals are Mayo-derived, unless otherwise designated. If an interpretive report is provided, the reference value field will state this.
1.21-2.70 mcg/mL
Interpretation
Provides information to assist in interpretation of the test results
A serum beta-2-microglobulin (beta-2-M) value of less than 4 mcg/mL is a good prognostic factor in patients with multiple myeloma. In a study of pretreatment serum beta-2-M levels in 100 patients with myeloma, it was reported that the median survival of patients with values greater than 4 mcg/mL was 12 months, whereas median survival for patients with values less than 4 mcg/mL was 43 months.
Cautions
Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances
Results determined by assays using different manufacturers or methods may not be comparable
Quantitation of specific proteins by nephelometric means may not be possible in lipemic sera due to the extreme light scattering properties of the specimen. Turbidity and particles in the specimen may result in extraneous light scattering signals, resulting in variable specimen analysis.
Clinical Reference
Recommendations for in-depth reading of a clinical nature
1. Bataille R, Magub M, Grenier J, Donnadio D, Sany J. Serum beta-2-microglobulin in multiple myeloma: Relation to presenting features and clinical status. Eur J Cancer Clin Oncol. 1982;18(1):59-66
2. Garewal H, Durie BG, Kyle RA, Finley P, Bower B, Serokman R. Serum beta-2-microglobulin in the initial staging and subsequent monitoring of monoclonal plasma cell disorders. J Clin Oncol. 1984;2(1):51-57
3. Norfolk D, Child JA, Cooper EH, Kerruish S, Ward AM. Serum beta-2-microglobulin in myelomatosis: potential value in stratification and monitoring. Br J Cancer. 1980;42(4):510-550
4. Dolan MJ, Lucey DR, Hendrix CW, Melcher GP, Spencer GA, Boswell RN. Early markers of HIV infection and subclinical disease progression. Vaccine. 1993;11(5):548-551
5. Karlsson FA, Wibell L, Evrin PE. Beta-2-microglobulin in clinical medicine. Scand J Clin Lab Invest. 1986;154:27-37
6. Greipp PR, Katzmann JA, O'Fallon WM, Kyle RA. Value of beta-2-microglobulin level and plasma cell labeling indices as prognostic factors in patients with newly diagnosed myeloma. Blood. 1988;72(1):219-223
7. Dietzen DJ, Willrich MAV. Amino acids, peptides, and proteins. In: Rifai N, Chiu RWK, Young I, Burnham CAD, Wittwer CT, eds. Tietz Textbook of Laboratory Medicine. 7th ed. Elsevier; 2023:chap 31
Method Description
Describes how the test is performed and provides a method-specific reference
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.; Version 2.4, 07/2019)
PDF Report
Indicates whether the report includes an additional document with charts, images or other enriched information
Day(s) Performed
Outlines the days the test is performed. This field reflects the day that the sample must be in the testing laboratory to begin the testing process and includes any specimen preparation and processing time before the test is performed. Some tests are listed as continuously performed, which means that assays are performed multiple times during the day.
Monday through Friday, Sunday
Report Available
The interval of time (receipt of sample at Mayo Clinic Laboratories to results available) taking into account standard setup days and weekends. The first day is the time that it typically takes for a result to be available. The last day is the time it might take, accounting for any necessary repeated testing.
Specimen Retention Time
Outlines the length of time after testing that a specimen is kept in the laboratory before it is discarded
Performing Laboratory Location
Indicates the location of the laboratory that performs the test
Fees :
Several factors determine the fee charged to perform a test. Contact your U.S. or International Regional Manager for information about establishing a fee schedule or to learn more about resources to optimize test selection.
- Authorized users can sign in to Test Prices for detailed fee information.
- Clients without access to Test Prices can contact Customer Service 24 hours a day, seven days a week.
- Prospective clients should contact their account representative. For assistance, contact Customer Service.
Test Classification
Provides information regarding the medical device classification for laboratory test kits and reagents. Tests may be classified as cleared or approved by the US Food and Drug Administration (FDA) and used per manufacturer instructions, or as products that do not undergo full FDA review and approval, and are then labeled as an Analyte Specific Reagent (ASR) product.
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.
CPT Code Information
Provides guidance in determining the appropriate Current Procedural Terminology (CPT) code(s) information for each test or profile. The listed CPT codes reflect Mayo Clinic Laboratories interpretation of CPT coding requirements. It is the responsibility of each laboratory to determine correct CPT codes to use for billing.
CPT codes are provided by the performing laboratory.
CPT codes are provided by the performing laboratory.
82232
LOINC® Information
Provides guidance in determining the Logical Observation Identifiers Names and Codes (LOINC) values for the order and results codes of this test. LOINC values are provided by the performing laboratory.
| Test Id | Test Order Name | Order LOINC Value |
|---|---|---|
| B2M | Beta-2-Microglobulin, S | 1952-1 |
| 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.
|
|---|---|---|
| B2M | Beta-2-Microglobulin, S | 1952-1 |