Synonyms: Beta-2 microglobulin, Beta-2 microglobulin urine, beta 2-MG.
Scientific editor: M. Merkusheva, PSPbGMU them. Acad. Pavlov, general medicine.
November, 2018.
Beta-2 microglobulin attributed to low molecular weight proteins, which are located on the outer membranes of all cells. The normal component of the blood stream is completely reabsorbed by the renal tubules and not supplied to the secondary urine. If its concentration in urine increased, we can talk about the diseases of the genitourinary system, cancer or autoimmune processes in the body.
In laboratory practice, beta-2 microglobulin in urine is a marker for proximal tubules pathologies kidney and oncomarker lymphoproliferative processes (together with the determination of beta-2 microglobulin blood).
Overview
The body of a healthy human beta-2 microglobulin is produced in strictly defined concentrations, circulating 107 hours in line with the blood and into the kidney. There is formed a plasma filtration process primary urine, which contains this and other products of metabolism. In the renal tubule reabsorption occurs residues plasma and low molecular compounds, thereby forming a secondary urine - just othodovaya liquid that stands out from longer needed body.
Since in the proximal tubule kidney microglobulin sucked back into the urine, they may remain only in traces. If their levels in the urine increases, it is necessary to consider the loss of tubular systems - various types nephritis (a consequence of autoimmune diseases such as lupus, renal amyloidosis, diabetic nephropathy, and et al.). This increase in the concentration of beta-2 microglobulin will be observed even at early stages of the disease, when the quality of glomeruli filtration rate and may remain in the normal range.
It should be understood that the beta-2 microglobulin is not a single criterion for the diagnosis of "jade." If a patient already diagnosed with renal involvement (interstitial nephritis, glomerulonephritis, nephropathy in the background cadmium intoxication, pyelonephritis and t. d.), the protein content in the urine will increase in proportion to the speed reduction glomerular filtration.
Assay for beta-2 microglobulin in urine is a common operation check procedure proximal tubules, which allows to evaluate the engraftment of the transplanted kidney and timely identification of its reaction rejection. In some cases use test for the differential diagnosis of inflammatory, infectious, viral and bacterial diseases of the urogenital system and urinary tract.
The lymphatic system is the main producer of beta-2 microglobulin, so the growth rate proliferation of its cells is always accompanied by an increase in serum protein concentration and urine. In this case the subject under suspicion of the following diseases: lymphoma, chronic lymphatic leukemia, leukemia, myeloma, Hodgkin's disease, etc... Lymphocytic cells are affected and in other serious pathologies (HIV, AIDS, Epstein-Barr virus, tsitomeaglovirus), which makes it advisable to simultaneous detection of beta-2 microglobulin and serumAnd in the urine.
testimony
- Differential diagnosis of renal failure, glomerular lesions associated with the device or the proximal tubule;
- Diagnosis and treatment of autoimmune nephritis;
- Monitoring of patients after kidney transplantation;
- Detection of atypical currents genitourinary diseases and excretory systems (cystitis, urethritis, nephritis) to accurate diagnosis and assessment of nephron tubules involvement in the inflammatory or infectious process;
- Monitoring of patients on hemodialysis;
- beta-2-microglobulin together with serum cystatin C is used for detecting reduction of glomerular filtration rate in critically ill children1.
Norms of beta-2 microglobulin in urine
Important! Rates can vary depending on the reagents and equipment used in a particular laboratory. Therefore, when interpreting the results it is necessary to use standards adopted precisely in the lab where to be tested. It is also necessary to pay attention to the units.
- 0-0.3 mg / L.
- 0-300 ng.
The complete absence of protein in the urine must be considered the norm.
The interpretation of the test results on the beta-2 microglobulin in urine carries hematologist nephrologist, oncologist, transplant urologist.
Important! Interpretation of the results is always carried out comprehensively. An accurate diagnosis on the basis of only one analysis impossible.
Increasing values
- Nephritis (renal damage) different etiologies: bacterial or interstitial, glomerulonephritis, pyelonephritis;
- Diabetic nephropathy (renal failure and vascular tissues against the raised sugar in diabetes);
- renal failure in acute or chronic form;
- The reaction of rejection of the transplanted kidney;
- Lymphoproliferative diseases: myeloma, lymphoma, leukemia, B-cell leukemia, Hodgkin's disease, etc .;
- Autoimmune disorders: systemic vasculitis, rheumatoid arthritis, lupus, disease Sjogren etc.;
- Viral diseases: cytomegalovirusHIV, Infectious mononucleosis, Epstein-Barr virus;
- Amyloidosis kidney (deposition of amyloid protein in the kidneys as a result of metabolic disorders);
- Acute toxicity (poisoning) body with chemical, toxic, medicinal components, alcohols, heavy metals.
On the results of the study may affect reception of lithium drugs, cyclosporine.
Training
To carry out the test using a biomaterial - a single serving of morning urine.
For 2-3 days prior to analysis it is recommended to exclude diuretics (diuretics) and consumption of foods / drinks having a similar effect.
Before collecting the urine is necessary to empty the bladder and drink 1-2 glasses of water. Then spend the toilet of external genitals and collect urine following urination in a clean container, which is necessary to fill only half. The label on the container should indicate the date of collection of the material, the patient's name, the total urine output (total urine sample from which the part is taken on the study). Biomaterial is required to deliver to the laboratory within 4 hours (max) after harvest.
sources:
- 1. J.D.Herrero-Morin, S.Malaga. Cystatin C and Beta2-microglobulin: Markers of Glomerular Filtration in Critically Ill Children. - Critical Care 2007; 11 (3).
- 2. M.Gooptu, MBBS. Beta2-Microglobulin. - Medscape, Sep 05, 2014.
- 3. A.A.Kishkun, prof. Manual for the laboratory diagnosis methods - GEOTAR-Media, 2007.
