Beta-2-Microglobulin, Urine
- Laboratory
- Quest Diagnostics
- Test code
- 4944
- Specimen
- Urine
- Fasting
- Not stated
- LOINC
- 1953-9
- Turnaround
- Set up: Mon-Sat
Laboratory assay overview
Beta-2-Microglobulin (B2M) is a low molecular weight protein that forms the light chain component of the histocompatibility antigen. It is synthesized by all nucleated cell types. It is an integral part of the class I MHC antigens and is present in all body fluids. B2M is filtered through the glomeruli of the kidney and is then reabsorbed and catabolised by the proximal tubular cells. In normal patients only trace amounts of B2M appear in the urine. Elevated urine B2M is seen in tubulo-interstitial disorders. Increased urine B2M is seen in cadmium exposure, diatrizoate, exercise, fever, nephrectomy, semen. There is evidence that monitoring B2M levels in HIV-infected individuals offers an independent predictor of progression to AIDS, leukemia and lymphoma.
Quest Diagnostics population reference ranges
Quest Diagnostics calculates these statistical intervals for this specific assay and demographic group, not as universal optimal targets.
| Population | Range |
|---|---|
| <18 Years | Not established |
| Adults | ≤0.20 mg/L |
View complete laboratory reference notes
<18 Years Not established Adults ≤0.20 mg/L
Quest Diagnostics test directory, test code 4944