Epic Test Code LAB49 Beta-2-Microglobulin, Serum
Additional Codes
MML Code: B2M
NY State Approved
YesPerforming Laboratory
Mayo Clinic Laboratories in RochesterReporting Name
Beta-2-Microglobulin, SMethod Name
Nephelometry
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Serum | Refrigerated (preferred) | 28 days | |
Frozen | 28 days | ||
Ambient | 14 days |
Specimen Required
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.
Blood Tube Draw Volume
Min 50% draw volume
Specimen Type
SerumSpecimen Minimum Volume
0.5 mL
Reference Values
1.21-2.70 mcg/mL
Report Available
Same day/1 to 2 daysDay(s) Performed
Monday through Friday
CPT Code Information
82232
Reject Due To
Gross hemolysis | OK |
Gross lipemia | OK |
Gross icterus | OK |
Useful For
Prognosis assessment of multiple myeloma
Evaluation of renal tubular disorders
Testing Algorithm
For more information, see Multiple Myeloma: Laboratory Screening
Special Instructions
Clinical Information
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 than4 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.
For more information see Multiple Myeloma: Laboratory Screening
Interpretation
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.
Specimen Retention Time
14 daysForms
If not ordering electronically, complete, print, and send Renal Diagnostics Test Request (T830)
Cautions
Results determined by assays using different manufacturers or methods may not be comparable