What is an immunoblot? This is a common method for laboratory diagnosis of human viral infections. He is considered one of the most accurate and reliable ways to detect the presence of HIV. In its reliability, it surpasses even enzyme-linked immunosorbent assay (ELISA). Immunoblot results are considered conclusive and final.
general information
Immunoblot - what is it? In order to recognize a person's HIV infection, it is necessary to undergo a method of laboratory testing of blood serum for the presence of antibodies. The method of immunoblotting is also called western blot (western blot). It is used to detect human viral infections as an additional expert method. It is necessary to confirm ELISA, a laboratory test that allows you to determine the presence of HIV antibodies in the blood. Immunoblotting rechecked a positive ELISA. It is considered the most sensitive, complex and expensive.
Destination
What is an immunoblot? This is a technique for laboratory testing of blood serum for the presence of antibodies to the virus. During the study, the specialist previously separates the virus proteins in the gel and transfers them to the nitrocellulose membrane. An immunoblot routine is designed to determine HIV at different stages. At the first stage, the purified virus from the components is subjected to electrophoresis, and the antigens included in its composition are separated by molecular weight.
The human immunodeficiency virus multiplies in a living cell, integrating its genetic information into it. At this stage, the person becomes a carrier of the HIV virus if it has been infected. The specificity of the disease is that for a long time it may not manifest itself in any way. The virus destroys lymphocytes, therefore, the human immunity is reduced, and the body becomes unable to resist infections. If HIV is correctly and timely treated, the patient will live to a very old age. Lack of therapy will inevitably lead to death. From the moment of infection, but without treatment, the maximum lifespan is no more than ten years.
Features
Immunoblot analysis is a reliable method that allows you to determine the presence of antibodies to HIV antigens of the first and second type. If a person is infected, antibodies appear within two weeks, which can be detected much later. The peculiarity of HIV is that the number of antibodies increases rapidly and remains in the patient's blood. Even if they are present, the disease may not manifest itself for two or more years. The ELISA method does not always accurately determine the presence of the disease, therefore, confirmation of the results by immunoblotting and PCR is required if the enzyme-linked immunosorbent assay showed a positive result.
Indications for appointment
What is this "immunoblot" already found out, but to whom is this study assigned? The reason for passing tests for the human immunodeficiency virus (HIV) by immunoblotting is a positive ELISA. It is necessary to go through an enzyme-linked immunosorbent assay for patients who will be operated on. In addition, an analysis should be done for women planning a pregnancy, as well as for everyone who leads an erratic sex life. Assign immunoblotting to patients with HIV if the results of ELISA are questionable. The following alarming symptoms may be the reason for contacting a doctor:
- sharp weight loss;
- weakness, loss of working capacity;
- an intestinal upset (diarrhea) that lasts for three weeks;
- dehydration of the body;
- fever;
- swollen lymph nodes in the body;
- the development of candidiasis, tuberculosis, pneumonia, toxoplasmosis, exacerbation of herpes.
The patient does not need to prepare before giving venous blood. 8-10 hours before the study, you can not eat food. It is not recommended to drink alcoholic and coffee drinks a day before giving blood, do heavy physical exercises, and experience excitement.
Where to do the analysis?
Where can I get an HIV test? ELISA, immunoblot studies are carried out in urban private clinics, the results are issued within a day. An urgent diagnosis is also possible. In state medical institutions, ELISA and immunoblotting are free of charge, according to the legislation of the Russian Federation. Mandatory tests for infectious diseases are pregnant women, as well as patients who are going to hospitalization or surgery.
How is the study conducted?
How is ELISA performed? Immunoblot positive / negative confirms or refutes the results of enzyme immunoassay. The research procedure is quite simple. The specialist collects venous blood, in time it takes no more than five minutes. After sampling, the injection site should be disinfected and sealed with a band-aid. The fence is carried out on an empty stomach, so after the procedure it does not hurt to eat a bar of dark chocolate or drink a sweet hot drink.
In order to get a referral for a free analysis at a state medical institution, you need to visit a general practitioner. In general, the immunoblot is not different from other blood tests by the method of sampling. The research technique is simple. If a virus is present in human blood, the body begins to produce antibodies to destroy it. Each virus has its own set of protein antigens. The detection of these antibodies is the basis of the method of immunoblotting.
Cost
How much is the analysis? An HIV immunoblot is not a cheap study. On average, a screening test by enzyme immunoassay methods costs from 500 to 900 rubles. Immunoblotting is a verification study, the cost of which is from three to five thousand rubles. More sophisticated methods are much more expensive. For example, for the analysis of polymerase chain reaction (PCR), you will need to pay about 12,000 rubles.
Interpretation of the result
The most common methods for diagnosing HIV infection are enzyme-linked immunosorbent assay and immunoblot. They are used to detect antibodies to the immunodeficiency virus in the blood serum. The presence of infection is usually confirmed by two tests: screening and confirmatory. Interpretation of the results of the study should be carried out by a doctor, he also makes a diagnosis and prescribes treatment. If the immunoblot is positive, it means that a virus is present in the human body.
A positive result should not be an occasion for independent treatment, since each patient may have his own picture of the disease. Qualitative analysis includes screening and verification. If the patient does not have a virus, then the result indicates "negative." If detected by a screening method, an additional verification study is performed. An immunoblot is an assay that confirms or refutes screening. If dark spots appear on the test strip in certain areas (protein localization sites), they are diagnosed with HIV. If the results are in doubt, tests are carried out for three months.
You can prevent infection with the immunodeficiency virus if certain rules are followed: avoid accidental sexual intercourse, use a condom during contact, do not take drugs. If the disease is detected in a pregnant woman, it is important to strictly follow the recommendations of the attending physician, do not forget to undergo examinations for the presence of the virus.