B2 microglobulin is normal, so everything is fine. Effect of b2-microglobulin (b2M) on the course and prognosis of chronic lymphocytic leukemia (CLL)

b-2 microglobulesn- oncomarker, an indicator in the diagnosis of inflammation various genesis, malignant diseases (malignant lymphomas, multiple myeloma). This is a low molecular weight protein that is synthesized daily in the body in an amount of 150 mcg. Excreted by the kidneys (filtered and catabolized by the renal tubules). The appearance of this protein in the urine primarily indicates a violation of renal filtration.

In adult humans, the production rate of b-2 microglobulin is relatively constant.

The increase in the level of concentration of b-2 microglobulin depends on the stage of the disease, the degree of malignancy and cell type. In patients with progressive pathology, the concentration of b-2-microglobulin is significantly higher than in patients during the stabilization period. High protein levels correlate with poor prognosis.

Normally, only trace amounts of beta-2 microglobulin are detected in the urine. Its plasma half-life is 107 minutes.

The level of beta-2 microglobulin in the blood increases with kidney failure(decreased renal clearance). With damage to the cells of the proximal tubules due to kidney disease, drug intoxication, toxic effects of heavy metals, etc., the excretion of beta-2 microglobulin in the urine increases.

The determination of beta-2 microglobulin in urine is used as a marker of damage to the proximal tubules of the kidneys. This test may be useful in the differential diagnosis of upper and lower urinary tract infections. Synthesis of beta-2 microglobulin is increased in many conditions associated with increased cell turnover and increased activity immune system: inflammation of all types, autoimmune disorders, antigenic response, transplant rejection, B-cell lymphoma, multiple myeloma, viral infections, including HIV infection, cytomegalovirus infection.

Limits of detection: 0.004 mg/l–2.5 mg/l

Indications:

• kidney pathology;
• differential diagnosis of upper and lower urinary tract infections;
• assessment of the degree of damage to the proximal kidneys during drug intoxication, toxic effects of heavy metals;
• control in kidney transplantation.

empty bladder(This portion of urine is poured into the toilet). Drink a large glass of water (200–250 ml). After about an hour, collect the urine in a sterile container with a lid. The urine collection container should be filled 1/3-1/2 full.

Interpretation of results
Units of measurement: mg/l.

Alternate units: mg% = mg/100 ml.

Unit conversion: mg/100 ml x 10 = mg/l.

Reference values:< 0,3 мг/л.

Boosting values:

• kidney disease with damage to the proximal sections;
• diabetic nephropathy;
• side effect medicines(carboplatin, cisplatin, gentamicin, nifedipine, tobramycin, radiopaque agents);
• increased turnover of lymphoid cells: inflammation with activation cellular immunity, multiple myeloma, Hodgkin's disease, malignant non-Hodgkin's lymphomas (lymphogranulomatosis), chronic lymphocytic leukemia, viral infections (HIV, cytomegalovirus, etc.), autoimmune diseases (systemic lupus erythematosus, etc.);
• intoxication with cadmium salts.

Beta-2 microglobulin- a marker of tumor diseases of the blood and an indicator of kidney damage.

Synonyms: thymotaxin,B2 M, thymotaxin,beta2-mmicroglobulin, β 2- microglobulin.

Beta-2 microglobulin is

complex protein with low molecular weight, up to 12 kDa. A particle of HLA antigens is located on the surface of every cell containing a nucleus. From the destroyed cells, beta-2-microglobulin enters and then is excreted by the kidneys with urine. It is present in minimal concentrations in all biological fluids.

Each person has a setHLA antigens are individual and unique. HLA act as a kind of "antennae" on the cell membrane, allow the body to recognize its own and foreign cells (bacteria, viruses, cancer cells, etc.), and, if necessary, launch an immune response and remove foreign material from the body.

The largest number of beta-2-microglobulin molecules is on B-lymphocytes, therefore, with the growth of a tumor from B-, the level of beta-2-microglobulin also increases. Being a tumor marker for some blood tumors, it is not specific for any one. The level in the blood directly depends on the mass of the tumor, which makes it possible to predict the course of the disease.

Beta-2 microglobulin is one of the blood.

With the destruction of a large number of cells (inflammation, necrosis), beta-2-microglobulin in the blood also increases.

Protein levels also depend on kidney function. Beta-2-microglobulin is filtered by the glomeruli of the kidneys along with water, vitamins and some proteins into the primary urine, but is almost completely reabsorbed in the proximal nephron (along with water, vitamins and proteins), i.e. does not enter the secondary urine. When the glomerulus is damaged, the filtration of beta-2-microglobulin is reduced, which leads to an increase in the index in the blood. And, conversely, in the pathology of the tubular apparatus, beta-2-microglobulin does not return to the blood, but is intensively excreted in the urine.

Beta-2-microglobulin can be examined in the blood, in (preferably in the morning) and.

Indications

• diagnosis of a tumor disease of unknown location
• suspicion of a neoplastic disease of the blood - diagnosis and ( additional method); beta-2-microglobulin is used to assess the stage and activity of the disease, the success of the treatment
• predicting the course of multiple myeloma
• suspected chronic renal failure
• control of patients with a transplanted (transplanted from a donor) kidney

Norm, mg/l

• the norm of beta-2-microglobulin in the blood is 1.0-2.4

Remember that each laboratory, or rather, laboratory equipment and reagents, has “its own” standards. On the form laboratory research they go in the column - reference values ​​\u200b\u200band the norm.

What influences the result?

• drugs - cyclosporine, cisplatin, carboplatin, aminoglycoside antibiotics, lithium preparations
• contrast agents
• age, gender - beta-2-microglobulin levels are higher in women, after 30 years - a gradual increase
• analysis method (ELISA, RIA, FIA)

Decryption

Reasons for the increase

1. Tumor diseases of the blood originating from lymphocytes:

• myeloma — malignant tumor bone marrow from plasma cells that, as a result of mutation, have become malignant
• - a malignant blood disease, characterized by uncontrolled division of mature atypical lymphocytes, in 95% of cases - B-lymphocytes, bone marrow is affected, The lymph nodes, spleen, liver
• - includes several dozen diseases in which the neoplasm originates at one of the stages of lymphocyte development

It is always necessary to rule out kidney disease!

An elevated level of beta-2-microglobulin in the blood during the diagnosis of a disease can only tentatively indicate the presence of a disease, since the specificity of the marker is low.

If the level of beta-2-microglobulin is assessed with an already known diagnosis, then on its basis it is possible to judge the size of the tumor, the prognosis, and the success of treatment.

A stable marker level or an increase after a course of treatment is an indicator of a poor response to therapy.

A negative beta-2-microglobulin test result is NOT proof of the absence of cancer.

2. non-tumor diseases

• as a result of any kidney disease (polycystic kidney disease)
• systemic and autoimmune diseases -,
• transplant rejection after

Synonyms: Beta-2-microglobulin, B2M, Thymotaxin, Beta2-Microglobulin.

Scientific editor: M. Merkusheva, PSPbGMU im. acad. Pavlova, medical business.
October, 2018.

Beta-2 microglobulin is produced by almost all cells of the body, and is also present in the main biological fluids: lymph, cerebrospinal fluid, urine, serum, etc. An increase in the content of beta-2 microglobulin indicates pathological processes, most often of a malignant nature.

An analysis for beta-2 microglobulin in the blood allows you to identify oncology in a patient (lymphoma, myeloma, etc.), serious inflammatory processes, as well as to establish the degree of damage to the central nervous system and renal apparatus.

General information

Beta-2 microglobulin is a simple protein that is present in the HLA histocompatibility antigen chain. It can be detected in all liquid media of the body, however, the level of beta-2 in the blood serum most reflects cellular metabolism (metabolism) and probable proliferation (reproduction, growth, increase in volume) of lymphocytes, which indicates a pathological process.

In an adult, the secretion of beta-2 protein is stable, so an increase in its concentration is a reason for differential diagnosis various diseases.

From the blood, beta-2 microglobulin enters the kidneys, where it is filtered and almost completely reabsorbed (absorbed). Thus, normally, this protein either does not enter the urine at all, or is found in the form of trace metabolites. The half-life of beta-2 microglobulin in the blood is just over 100 minutes (2.5 hours).

The concentration of the oncomarker beta-2 in the blood increases with a violation of the kidneys, most often with insufficient filtering function. A similar problem may result from:

• damage to the proximal tubules as a result of past inflammatory and infectious processes;
• hereditary kidney disease;
• intoxication with heavy metals, alcohol, drugs, other chemicals;
• radiation exposure (irradiation) on the body.

The most common reasons for an increase in the level of beta-2 microglobulin in the blood are:

• increased activity of the immune system (reaction to pathogens: fungi, viruses, bacteria, etc.);
• autoimmune pathologies;
• antigenic response of the body, including oncological processes (myeloma, lymphoma, and others);
• transplant rejection reaction.

The highest content of beta-2 microglobulin in B-lymphocytes. Therefore, the level of this protein increases significantly in malignant processes, which are characterized by aggressive growth of tumor tissues and a tendency to metastasize.

The determination of a marker in the blood is used in oncohematology to predict the relapse and remission of a malignant disease. However, the analysis is not specific to a particular tumor.

Hypersecretion of beta-2 microglobulin is directly related to the development of amyloidosis, especially in people on hemodialysis. Beta-2 microglobulin is the main component of amyloid fibrils. It accumulates in the joints and leads to destructive osteoarthropathy and pathological fractures. The most severe complication: deposition of beta-2 amyloid in the paravertebral ligaments and intervertebral discs which leads to paralysis.

Indications

• Definition various kinds blood cell cancer;
• Differential diagnosis of tubular and glomerular pathologies of the kidneys;
• Diagnosis and treatment of chronic renal failure;
• Determination of the stage and form of the myeloma process, evaluation of the effectiveness of treatment, identification of the size of the tumor mass;
• Forecast of the development of others cancer: lymphomas, leukemias, etc.;
• Monitoring the patient's condition after kidney transplantation (to determine the rejection reaction);
• Therapy of patients who were in contact with mercury and cadmium concentrates, received intoxication with chemicals, drugs, alcohol, were exposed to radiation;
• Assessment of the state of the central nervous system against the background of any oncological pathologies, AIDS;
• Diagnosis of diseases lymphatic system accompanied by activation immune reactions(multiple sclerosis);
• Diagnosis and treatment of severe viral infections(cytomegalovirus, HIV, etc.);
• Monitoring the course and treatment of autoimmune diseases.

Deciphering the test for beta-2 microglobulin in the blood can be carried out by an oncologist, transplant surgeon, nephrologist and therapist.

Beta-2 microglobulin is normal

Important! Regulations vary depending on the reagents and equipment used in each particular laboratory. Therefore, when interpreting the results, it is necessary to use the standards adopted in the laboratory where the analysis was taken. You also need to pay attention to the units of measurement.

Important! The interpretation of the results is always carried out in a complex manner. It is impossible to make an accurate diagnosis on the basis of only one analysis.

Increasing values

• Systemic inflammatory, infectious, viral and bacterial processes;
• Autoimmune diseases: multiple sclerosis, lupus erythematosus, Sjögren's syndrome, rheumatoid arthritis, etc.;
• Oncohematological diseases: Hodgkin's disease, multiple myeloma, B-cell leukemia, non-Hodgkin's lymphoma, etc.;
• Viral infections: mononucleosis, HIV (AIDS), cytomegalovirus, etc.;
• Kidney pathology: failure, pyelonephritis, glomerulonephritis, kidney infarction, etc.;
• Kidney transplant rejection;
• Hemodialysis (in some patients, the level of beta-2 microglobulin is increased).

An increase in beta-2 microglobulin in the cerebrospinal fluid is observed during an exacerbation multiple sclerosis, dementia with AIDS-associated complex, with meningeal spread of acute leukemia and malignant lymphoma, neurosarcoidosis.

In the presence of renal pathologies, a high level of beta-2 microglobulin in the blood and reduced in the urine indicates damage to the glomerular apparatus of the kidney. If the protein concentration decreases in serum, but increases in urine, then the cause should be sought in the renal tubules.

An increase in beta-2 microglobulin values ​​immediately after a kidney transplant may indicate the onset of a graft rejection reaction.

If the protein grows in the blood and cerebrospinal fluid against the background of oncology (leukemia, myeloma, etc.), as well as viral diseases(HIV, AIDS), this may mean that the central nervous system is involved in the pathological process.

Decreased concentration of beta-2 microglobulin or its complete absence in the blood should be considered normal.

Factors influencing the result

• Systemic diseases that accelerate the synthesis and breakdown of cells ( cytomegalovirus infections, inflammation and autoimmune pathologies that activate the immune system);
• Medications: cisplatin, carboplatin, cyclosporine, antibiotics (aminoglycosides), lithium preparations, and others;
• Recent x-ray and MRI with contrast;
• recent PET/CT (positron emission and computed tomography);
• The method of performing a blood test (it is recommended to be examined in the same laboratory).

Training

Biomaterial for research: venous blood.

Biomaterial sampling method: venipuncture of the cubital vein.

Mandatory conditions: strictly on an empty stomach (after a 10-hour overnight fast). Immediately before the manipulation, only pure non-carbonated water is allowed to be consumed.

Additional requirements:

• the day before - a light dinner without fatty, heavy and spicy foods;
• per day - refusal of alcoholic and tonic drinks, smoking, physical and emotional stress;
• in 2-3 hours - the absence of psycho-emotional stress;
• for 3 hours - refusal to chew tobacco and smoking.

Important! 1-2 weeks before the planned date of the analysis, it is necessary to stop / suspend any courses of treatment (physiotherapy, massage, exercise therapy, etc.), reschedule for more late deadline medical and diagnostic manipulations and cancel the appointment medicines. If it is impossible to fulfill this requirement, it is necessary to coordinate in advance with the attending physician the applied therapy regimen, dosage and types of drugs.

Modern methods laboratory diagnostics allows you to identify any violations in the body. In particular, testing for beta-2-microglobulin gives the doctor an idea of ​​the condition of the kidneys and the immune system. When is this analysis prescribed and how can it be useful?

What is beta-2 microglobulin?

Beta-2 microglobulin is a small protein found on the surface of many nucleated cells in the body. Beta-2-microglobulin in in large numbers presented on lymphocytes. And the level of this protein reflects the proliferation of lymphocytes and their cell turnover. With various pathological conditions immune system, in particular in lymphoproliferative diseases, there is an increase in beta-2-microglobulin in the blood.

It is also known that beta-2-microglobulin undergoes filtration in the renal glomeruli. And then in the renal tubules re-absorbed into the blood. Therefore, healthy person only traces of beta-2-microglobulin are determined in the urine. The detection of an increase in the concentration of this protein in the urine indicates damage to the kidney tubules.

Oncomarker beta-2-microglobulin - what does it show?

Beta-2 microglobulin is found in all body fluids. For diagnostic purposes, the protein is determined in the blood, urine, cerebrospinal fluid. The determination of beta-2-microglobulin in the blood is indicated for suspected hematological proliferative diseases, and in the urine for kidney pathology.

So, in what specific cases is a blood test for beta-2-microglobulin indicated?

• To detect multiple myeloma, determine the severity and stage of cancer, make a prognosis;
• To determine the extent of prevalence, possible metastasis of leukemia and malignant, prognosis.

A blood test for the oncomarker beta-2-microglobulin, unfortunately, does not have high specificity. Therefore, the test cannot be used for the primary diagnosis of oncohematological diseases. However, with the diagnosis of lymphocytic leukemia, the doctor may prescribe a periodic passage this study, because the results allow you to estimate the extent of the disease. Thus, a high level of this protein indicates an accelerated cellular turnover of lymphocytes and a significant prevalence of the malignant process.

A urine test is usually ordered along with a blood test. This approach increases the specificity of the test. In general, a urinalysis for beta-2-microglobulin is prescribed in such cases:

• To detect renal pathology;
• For differential diagnosis between glomerular and tubular disorders in the kidneys;
• For grade evaluation ;
• For early detection rejection.

For a more detailed assessment of impaired renal function, the patient is also prescribed urine tests for creatinine, microalbumin, and.

Oncomarker beta-2-microglobulin - norm and interpretation

For research, blood is taken from a vein or a portion of morning urine. It is advisable to carry out the procedure in the morning on an empty stomach. Non-carbonated water is allowed. On the eve of the study, you need to stop drinking alcoholic beverages and fatty foods as these factors may affect the analysis.

The rate of beta-2-microglobulin in the urine for people of all ages is up to 0.3 mg / l.

The reasons for the increase in protein in the urine are such pathological conditions:

1. Kidney diseases with damage to the renal tubules (this is observed with, amyloidosis, diabetic nephropathy);
2. Lymphoproliferative diseases (multiple myeloma, and non-Hodgkin's lymphoma, lymphocytic leukemia);
3. Autoimmune diseases, acute viral infections;

note

Norms of values ​​of beta-2-microglobulin in the blood differ in different age groups. So, in children (especially in newborns) there is a higher level of protein. At the age of up to six months, the norm of beta-2-microglobulin in the blood is up to 3.324 mg / l in boys and up to 3.774 mg / l in girls.

The norm of beta-2-microglobulin in the blood in adults is up to 2.329 mg / l. An increase in beta-2-microglobulin in the blood is associated with an increase in protein synthesis, as well as a violation of its excretion.

Microglobulin is a marker of renal tubular damage.

This indicator is often used in oncohematology, that is, in the branch of medicine devoted to the oncological pathology of the hematopoietic system, as well as in nephrology as an early indicator of damage to the proximal tubules of the kidneys. Accordingly, this marker can be examined in blood and urine.

Beta-2-microglobulin is a protein belonging to the human leukocyte antigen (HLA) complex, the molecules of which are found on most cells human body. This protein is associated with adjacent molecules alpha-1 and alpha-3, and together they belong to the major histocompatibility complex class 1 (MHC 1), which is absent only on erythrocytes and trophoblast cells.

It was noted that the concentration of the indicator in the blood is especially correlated with the number of lymphocytes, on the surface of which there are most of these molecules, therefore it is most convenient to monitor the proliferation of these cells, which is important in the field of oncohematology.

Second important point is a matter of protein excretion from the body. The lifetime of beta-2-microglobulin is about 3.5 hours, respectively, normally it is actively produced and actively eliminated by the kidneys. If it is not possible to utilize the protein from the plasma and the renal clearance indicators have decreased, one can suspect the pathology of the filtering apparatus of the kidneys, which is important in the field of nephrology and transplantation.

Normal values ​​​​of the indicator

Norm values ​​depend on age

Often the laboratory in which the analysis is carried out indicates the reference values, taking into account the errors of the equipment, therefore, in different diagnostic centers normal performance may differ slightly from each other.

The normal concentration of beta-2-microglobulin in the blood correlates with a person's age. In children of the first six months of life, quite high rate of this protein: on average - 1.6-4 mg / l. At the age of 6-12 months, the indicator decreases to 0.8-2.5 mg / l. In children under 7 years of age, the protein level is kept at a fairly stable level of 0.7-2.3 mg / l, after which it declines - 0.6-1.7 mg / l. For persons over 18 years of age, the rate of 0.67-2.3 mg / l is considered the norm.

The level of beta-2-microglobulin in the urine is more stable - less than 0.3 mg / l, regardless of age.

Increasing the indicator: causes, signs and symptoms

The study is used to detect viral diseases

An increase in the values ​​of beta-2-microglobulin in the blood usually indicates one of the processes:

• Tumor lesions of the hematopoietic system, lymphoproliferative processes. The most common diseases are lymphocytic leukemia, myeloma, Hodgkin's lymphoma, non-Hodgkin's lymphoma.
• Autoimmune processes associated with aggressive action immune cells on tissues and organs of the patient. The etiology is usually unknown. Predisposing factors are genetic mutations, hereditary predisposition, the effect of the virus genome on human cells. The most common diseases: systemic lupus erythematosus, Sjögren's syndrome, systemic scleroderma, rheumatoid arthritis.
• Viral diseases, which are characterized by lifelong persistence of the virus in the human body. For example, HIV, cytomegalovirus, Epstein-Barr virus. The listed infectious agents destroy the cells of the lymphoid series, as a result of which the concentration of the protein contained in them increases in the blood serum.
• Kidney damage: transplant rejection, CKD, lupus nephritis, infections, toxins.

Beta-2-microglobulin is an important indicator in nephrology

An increase in the values ​​of beta-2-microglobulin in the urine can be in two cases:

Symptoms and signs depend on the specific pathology.

For example, with kidney damage, edematous syndrome is often noted with predominant swelling of the face, urination may be accelerated or reduced, urine may be cloudy, dark or clarified, sometimes it acquires an uncharacteristic odor. Often the patient has pain in the lumbar region, fever, chills may appear. In blood tests, it is important to monitor the indicators of erythrocytes, leukocytes, ESR, CRP, creatinine, urea, and electrolytes.

In the case of hematological diseases, for example, lymphoblastic leukemia, the patient is worried about intoxication cider, anemia, thrombocytopenia, an increase in the size of the liver, spleen, etc. In the case of myeloma, there is destruction of the bones, often the skull, vertebrae. The kidneys are affected, symptoms of anemia occur, the level of calcium and serum paraprotein is increased in the blood. In the case of oncohematological diseases, the most informative indicator is the cytological picture of the bone marrow.

Decrease in the indicator: causes, signs and symptoms

Patients with low level indicators should be further examined

A decrease in the index in the blood does not carry a special diagnostic value; it occurs in the case of

• successful treatment of oncohematological diseases;
• with increased excretion of protein in the urine (the kidneys should be examined further).

A low rate of beta-2-microglobulin in the urine (down to 0 mg / l) is the norm.

Indications for the study

If an autoimmune process is suspected, a study is prescribed

1. Suspicion of an oncohematological process in the body (leukemia, lymphoma, multiple myeloma).
2. Suspicion of an autoimmune process in the body, assessment of disease activity.
3. Pathological processes in the kidneys:
   • in chronic renal failure due to autoimmune processes, diabetes, vascular pathology kidneys;
   • with intoxication due to the action of heavy metals (cadmium, mercury, lead), chemical compounds, including drugs;
   • monitoring the condition of the kidney after its transplantation;
   • with difficulties in localizing the infectious process in the urinary system (differences in inflammation of the upper and lower urinary tract).

Preparation for analysis

Medications should be discontinued the day before the test.

This analysis usually does not require careful preliminary preparation. Recommendations before a blood test are universal:

• it is advisable to donate blood in the morning on an empty stomach (after an overnight fast of 8-10 hours), or at any time of the day not earlier than 4 hours after the last meal;
• before the study, you can drink water in moderation, but it is better to wait a little with tea, coffee, soda and alcohol;
• on the eve of the study (for 2-3 days) avoid extremes - food overload with high-calorie food and hunger;
• do not smoke 30-60 minutes before the analysis;
• it is desirable to limit heavy physical, mental stress and physiotherapy 1-2 days before the analysis;
• drugs that are not vital for the patient are also recommended to be canceled 2-3 days before the study.

When taking urine for analysis, one should follow the rules of hygiene when collecting urine, use a new sterile container, collect urine directly on the day of analysis 1-3 hours before it.

Interpretation of test results

The doctor interprets the results

The laboratory issues a conclusion on the concentration of protein in the blood or urine. Usually, the conclusion indicates the normal reference values, the unit of measurement adopted in this laboratory (more often - mg / l), as well as the indicators of beta-2-microglobulin in a particular patient. The laboratory does not give clinical conclusions, but it can list a number of pathologies in which the result can be increased.

A clinical diagnosis can only be established by a hematologist, nephrologist or other doctor competent in this field. To establish a specific diagnosis, one analysis for beta-2-microglobulin, as a rule, is not enough, it is included in a large diagnostic complex, which may include general analyzes blood and urine biochemical analyzes, analyzes of puncture biopsy of the bone marrow, lymph nodes, imaging research methods (ultrasound, radiography, CT, MRI) and many others.

What can affect the result?

Exercising the day before can skew test results

1. Wrong preparation.
2. Conducting a study without taking into account the medications taken.
3. Malfunction of equipment in the laboratory.

Correction of indicators

Correction of the level of beta-2-microglobulin occurs in the case of treatment of the patient from the main pathological process in the body. For example, oncohematological diseases are treated in stationary conditions, using long-term chemotherapy, during which you can use the indicator of beta-2-microglobulin to track the dynamics and reduce lymphoid proliferation in the body.

Diseases are treated only by specialized doctors, for example, hematologists, nephrologists, rheumatologists, infectious disease specialists.