If certain types of malignant tumors are suspected, in addition to diagnostic procedures and blood tests, urinalysis is also prescribed.
In urine, a Bens-Jones protein can be detected in a number of cancers, its definitions help determine the diagnosis, and serve as a marker for the quality of the prescribed treatment.
Indications for the
study. In the urine of a healthy person, Bens-Jones protein can not be contained.
This urine element is a low molecular weight protein consisting of light chains of immunoglobulins. To develop this protein begins with plasma cells at the stage of formation of a number of malignant lesions.
Produced protein moves along the blood vessels along with blood flow, enters the kidneys and is excreted by urination.
If a Bens-Jones protein is found in the urine under investigation, this may indicate a development in the patient:
- Myeloma is a circulatory disease in which tumors are localized in the bone marrow.
- Plasmocytoma is a pathology of th
e neoplastic nature of plasma cells. This disease leads to frequent and serious infections and to the destruction of bones.
- Amyloidosis of the primary - a disease characterized by a violation of protein metabolism.
- Waldenstrom Macroglobulinemia - monoclonal gammopathy with malignant course.
- Idiopathic monoclonal gammopathy is a disease that occurs as a result of pathological production of immunoglobulins. Such a violation in the body leads to dysfunction of the kidneys and other organs.
- Chronic lymphocytic leukemia is a cancer that covers the bone marrow, lymph nodes, liver and spleen.
- Osteosarcoma is a malignant lesion of bone tissue with early metastasis.
- Endotheliosis - pathology of blood vessels.
- Lymphatic leukemia.
Bens-Jones protein in urine
Protein in urine should not be, in exceptional cases, its traces may be found. If the protein is determined in the urinalysis, then this condition is designated by the term proteinuria.
A more accurate study of urine in some diseases reveals a low molecular weight protein, such a change is referred to as prerenal proteinuria. This pathology is not characterized by damage to the renal tubules and filters, and if the kidneys function in the normal regime, then there is no reverse absorption of protein bodies.
Extrarenal or false proteinuria does not lead to impaired renal function and indicates most often an infectious or malignant process.
Proteinuria is found in patients with myeloma in almost 2/3 of the cases. At the same time, 20% of these patients have Bence-Jones myeloma.
Differentiation of low-molecular protein in urine is possible as a result of humoral changes in the B-system of immunity. Detection of the Bence-Jones protein is evaluated as one of the most important diagnostic features of the above diseases.
In the study, it is important to correctly classify proteinuria - λ-protein has a greater nephrotoxic effect compared to κ-protein.
How to pass the test?
The quality of the urine test for Bens-Jones uroproteins depends on how the patient's recommendations on the collection and delivery of the biological fluid are observed.
In general, laboratory assistants are advised to adhere to several rules:
- The results will be reliable if about a week you stop using excess liver and meat. The day before the test, you do not need to drink carbonated drinks, alcohol, and you need to exclude foods that affect the color change of urine, such as beets, blackberries, carrots, blueberries. The doctor may prohibit and take certain medications, so you should always inform about the treatment.
- Collect urine in a clean container - it can be a special drug store or a glass jar with a lid. The capacity must first be doused with boiling water.
- Protein is detected in the morning urine, in its average portion. Beforehand, you need to wash yourself without using gels or soap. To study enough 50 ml of liquid.
- Deliver the analysis to the center of the study should be no later than two hours from the time of its collection.
The concentration of a low molecular weight protein can also be established by immunoelectrophoresis. In this case, specific sera are used against the protein chains of the immunoglobulin fractions.
At the lowest concentrations, the Bens-Jones uroprotein can be determined by the precipitation reaction carried out with sulfosalicylic acid.
By the type of immunoglobin produced in the body is distinguished:
- Pathological changes in the light chains - the production of Bren-Jones uroprotein.
- Glomerulopathies, that is, the production of other types of immunoglobulins.
Other combinations of pathological changes in the kidneys are not excluded. Developing nephropathies are the result of diseases such as myeloma, Waldenstrom's disease, lymphatic leukemia with a chronic character of the course.
Bens-Jones proteins have molecules with a mass of no more than 40 kD, due to this they pass kidney filters unimpeded, then they decompose into amino acids and oligopeptides with the help of lysosomes.
The overabundance of light chains passing through the kidneys provokes the development of catabolism dysfunction, which can cause necrotic changes in the tissues of the renal tubules.
Protein bodies interfere with reabsorption, and if the light chains are connected with proteins called Tamm Horsfall, protein cylinders begin to form in the distal renal tubules.
In myeloma disease
Multiple myeloma is a pathological change in the body, characterized by the production of light immunoglobulin chains in place of normal high-grade ones. During the diagnosis of the disease, urine analysis is necessary to determine the quantitative content of protein bodies.
The subtype of myeloma is established based on serum analysis. The determination of the Bence-Jones protein and its quantitative content explains the sclerosis of the kidney stroma, which leads to renal failure.
The main signs of myeloma:
- Constant or periodic pain in the bones.
- Violations of the process of urination.
- Fluid retention in the body.
- Hematomas on the body that occur under the influence of the most insignificant factors.
Myeloma is most often detected in men aged 60 years. In their history, a genetic predisposition, immunosuppression, a tendency to obesity, exposure to radioactive and toxic substances is determined.
Determination of the Bence-Jones protein
To detect a specific protein in urine, special laboratory diagnostic methods should be used. The most commonly used immunofixation method.
First, the proteins are separated by electrophoresis, then immunomixing is performed using special sera.
Protein binding to immunoglobulin antibodies leads to the formation of immune complexes whose structure is evaluated after staining.
Unreliable methods for the detection of Bens-Jones uroproteins are methods where the heating is used up to 100 degrees or secondary precipitation after cooling. Indicators for the detection of light chains of immunoglobulins are not suitable.