Why the HIV test sent a recheck. If the test result for HIV is negative: what does it mean and can there be a mistake. Diagnostic errors in pregnant women

Testing for HIV positive - however, sounds like a death sentence for many. The presence of this epic disease speaks of a viral attack that kills cells, but not the presence of AIDS.

The question of what to do if an HIV test is positive is of concern to many. But, firstly, a doctor's prescription to take an analysis or an immunodeficiency test does not mean that the subject will have a positive result. Second, by following the healing therapy, life can continue in the same colors as before. The main thing is to detect in time an infection that affects the cells of the human body.

HIV (Human Immunodeficiency Virus) is an infectious disease that destroys the body's immunity. The presence of a virus in human blood means that a process has been launched in the body that kills healthy cells that are responsible for immunity and well-being.

In other words, the virus absorbs the body's ability to fight all sorts of diseases and infections, even in the smallest concentration, turning a simple cold into a real war for life.

The immunodeficiency virus is often identified with AIDS. The status of HIV positive in its advanced form may well lead to AIDS. AIDS, as you know, is the result of the development of the last stage of severe immunodeficiency. In fact, if a person is a carrier of the virus, this does not mean that he is sick with a disease such as AIDS, which is a much broader concept.

Connivance in the form of a neglected form of the immunodeficiency virus can be fatal for a person. Do not do this - ignore the risks, because not a single drug has yet been invented in the world to cure AIDS. So this is just one thing - you need to do an infection test on time if you have the slightest suspicion of infection, because it can be wrong.

HIV - ways of infection and symptoms

The immunodeficiency virus is transmitted mainly through sexual contact with an infected person. Other routes of infection are known as through:

• with blood transfusion in laboratory conditions (donated blood is always checked for infections, but small concentrations of the virus can pass by);
• during the contact of the mother with the child (during gestation, feeding or during childbirth);
• there may be infection through injections (needles), non-sterile devices and instruments (manicure supplies), and so on.

The symptoms of the primary manifestation of HIV infection are manifested as follows after only 6 weeks:

• sore throat (aching, when swallowing even outside meals);
• chills;
• muscle pain (not to be confused with exercise);
• if the sores in the mouth do not heal for a long time;
• there may be increased sweating during sleep;
• partial memory loss;
• a constant state of fatigue, but not as a result of overwork;
• inflammation of the lymph nodes in the body;
• pneumonia.

The procedure for examination for HIV infection

The main method for detecting HIV infection is testing for HIV antibodies. Examination for HIV infection (including anonymous) is carried out in medical institutions of all forms of ownership with the informed consent of the patient in strict confidentiality, and in the case of examination of minors under the age of 14 - at the request or with the consent of his legal representative. Testing is voluntary and is carried out with mandatory pre- and post-test counseling on HIV prevention issues.

Compulsory medical examination for HIV infection is subject to:

• Donors of blood, blood plasma, sperm and other biological fluids, tissues and organs (including sperm).
• Pregnant women.
• Children born to HIV-infected mothers.
• The following employees are subject to mandatory medical examination to detect HIV infection upon admission to work and during periodic medical examinations:

• Doctors, middle and junior medical personnel of centers for the prevention and control of AIDS, health care institutions, specialized departments and structural units of health care institutions, engaged in direct examination, diagnosis, treatment, service, as well as conducting forensic medical examination and other work with persons infected the human immunodeficiency virus, having direct contact with them;
• Doctors, middle and junior medical personnel of laboratories (groups of laboratory personnel) who screen the population for HIV infection and study blood and biological materials obtained from persons infected with the human immunodeficiency virus;
• Scientists, specialists, employees and workers of research institutions, enterprises (industries) for the manufacture of medical immunobiological preparations and other organizations whose work is related to materials containing the human immunodeficiency virus;
• Medical workers in hospitals (departments) of the surgical profile upon admission to work and thereafter once a year;

• Persons doing military service and entering military educational institutions and military service by conscription and contract, when conscripted for military service, when entering service under a contract, when entering military universities of ministries and departments that establish restrictions on the recruitment of persons with HIV infection;
• Foreign citizens and stateless persons when applying for a citizenship permit or residence permit, or a work permit in the Russian Federation, when foreign citizens enter the territory of the Russian Federation for a period of more than 3 months.

• Patients with a range of clinical indications that indicate the presence of HIV.
• Patients with suspected or confirmed diagnosis: drug addiction, sexually transmitted infections, hepatitis B, C, pulmonary and extrapulmonary tuberculosis.
• Vulnerable groups of the population: homosexual and bisexual people, commercial sex workers, clients of commercial sex workers, persons with promiscuity, persons in prison.
• Recipients of blood products.
• Persons who have sex with HIV-infected or sexually transmitted infections.
• Health care workers who have received micro-injuries while performing professional duties.
• Patients who have been injured by a healthcare professional in their care.
• Family members of HIV-infected patients.

REMEMBER: Accepting or refusing to be tested for HIV should not affect the quality of care.

Potential test results and seronegative window period:

• Positive test result means that the person has antibodies to HIV. This gives reason to believe that the person is HIV-infected. A doctor's consultation is required.
• Negative test result means that no antibodies to HIV have been detected. However, a negative test result for HIV antibodies may not always mean that a person is not infected, since there is a period of “seronegative window.” It takes the body from two weeks to three months to develop antibodies in an amount sufficient for their detection by the test system (in rare cases up to a year). This period of time is called "Window period"... Testing during this period may give a negative result, so the analysis should be repeated. IN "Window period"an infected person's blood, semen, vaginal secretions, and breast milk already contain enough virus to infect others.
• Undefined (questionable) test result: It is necessary to retest for antibodies to HIV by immune or linear blot after 2 weeks, 3 and 6 months. If negative results are obtained in ELISA, then further research is not required. If, 6 months after the first examination, uncertain results are again obtained, and the patient does not have risk factors for infection and clinical symptoms of HIV infection, the result is regarded as false positive. At the same time, in the presence of epidemiological and clinical indications, the studies are repeated as directed by the attending physician or epidemiologist. While the final HIV test result is unknown, the recommendations for behavior change are the same as for those who test positive.

Research results are not reported by phone,
but only during a personal conversation with the subject.

Pre-test and post-test counseling

Pre-test and post-test counseling at the AIDS Center is far from a formal procedure. This is not education or condemnation of the patient's behavior that led to infection, but a reasonable analysis of the current situation and correction of further behavior, including risky ones. Annually it is about 2600-2700 pre-test and 3400-3500 post-test consultations. The quality of the counseling provided determines, among other things, the patient's subsequent desire to be monitored at the AIDS Center and his commitment.

Every year, the Center, thanks to the counseling of persons who applied after casual sex or practicing other forms of risky behavior, prevents about 180-240 cases.

The waiting period for test results can be important for a person's decision to change risky behavior. During this period, many for the first time think about HIV as a personal problem, realize the need to change behavior, therefore, the possibilities of pre-test counseling should be fully used in order to prevent HIV infection.

Pre-test counseling

Pre-test HIV counseling is a dialogue between a patient and a specialist to discuss an HIV test and the possible consequences of knowing their HIV status . Such counseling leads to an informed decision to take the test or not to take the test.

The following points should be covered in the interview before HIV testing:

• behaviors associated with the risk of HIV infection
• the benefits of being tested, including the range of care available to patients who test positive for HIV
• ways of HIV transmission, prevention measures; testing procedure
• possible consequences of finding out HIV status (for personal life, practical conclusions)
• procedure for obtaining informed consent for testing
• procedure for issuing test results
• ways to get further assistance

As a result of pre-test counseling, the patient:

• receives information about HIV infection, HIV antibody test, HIV prevention measures, possible consequences of testing
• receives an objective assessment of the presence in his life of the risk of contracting HIV infection
• makes an informed decision about being tested for HIV antibodies
• ponders the possibilities of changing his / her risk-taking behavior of HIV infection

At the end of the consultation with the patient the following issues are discussed:

• What test result does he expect and why?
• What will he do if he doesn't get the result he hopes?
• What will change in his life if the result is positive?
• What will change in his life if the result is negative?

Post-test counseling

The results of the study are not reported by phone. Post-test counseling is a dialogue between a patient and a specialist to discuss HIV test results, provide relevant information, provide support and referrals to other professionals, and develop behaviors that reduce the risk of infection if test results are negative or reduce the risk of HIV transmission others if they are positive. The test result can be negative, uncertain or positive.

Post-test counseling in case of negative result is carried out taking into account the degree of risk of HIV infection in the patient. Patient low risk With regard to HIV infection, the doctor recalls the basic information provided before testing, discusses the least risky behavior with regard to HIV infection, and offers support in the form of follow-up visits, possible phone calls to reinforce the attitude towards safe behavior.

With the patient high risk regarding HIV infection, the physician should discuss the significance of the test result, review the basic information provided prior to testing, remind the patient of the window period, and recommend retesting after 3-6 months. The doctor should also return to the question of the least risky behavior in relation to HIV infection, discuss the need to use condoms, and - if there is a history of drug use - draw the patient's attention to the need to maintain the sterility of injecting equipment.

If blood is tested for antibodies to HIV by immune blotting, there is a possibility that undefined outcomebecause of

• mistakes when setting the test;
• the patient has other acute and chronic diseases;
• seroconversion phenomena.

If an undetermined result is obtained, the doctor should discuss with the patient the reasons and significance of the result obtained, recommend that the test be repeated, recommend that behavior is less dangerous in terms of HIV transmission, and refer the patient to an AIDS center for further monitoring.

ABOUT positive result the HIV test is reported to the patient by the doctor who ordered the examination.

When reporting a positive test result, the consultant

• communicates the result clearly and concisely;
• provides time for awareness of the message;
• assesses the patient's response to a message about the presence of antibodies to HIV;
• listens to the patient's thoughts and concerns about his diagnosis;
• listens to the patient's story about feelings about HIV infection;
• explains that the issue of the patient's prospects will be discussed in more detail after the completion of the examination at the AIDS Center;
• explains in simple words what HIV is, how it affects the immune system, the difference between HIV and AIDS;
• explains that the diagnosis of HIV infection, the stage of the disease will be finally determined at the center for the prevention and control of AIDS by an infectious disease doctor based on clinical, epidemiological and laboratory data;
• draws attention to the importance of adhering to the least dangerous behavior in relation to HIV infection, sexually transmitted diseases, which can suppress immunity and contribute to the progression of the disease; recommends using condoms during sexual intercourse, when using drugs, use disposable syringes and needles without passing them on to other users, monitor the sterility of the drug solution and the container from which it is drawn;
• explains responsibility for changing behavior in order to avoid transmitting HIV to others;

Thus, counseling while testing for HIV antibodies is not only a mandatory, but also an effective way of individual preventive work with people on HIV infection. Many people for the first time think about this disease in relation to themselves, realize the individual degree of risk, receive the necessary information, i.e. take the first step towards changing behavior.

Skilled counseling also helps people cope if they test positive, and thus makes a significant contribution to preventing suicide and other desperate behavior.

Positive result

What does it mean?

If you donated blood for HIV at the AIDS Center, hospital or clinic, then a positive result of such a test means that your blood contains antibodies to the human immunodeficiency virus. Antibodies are made by the body to fight off infections (viruses or bacteria) that have entered the body. The presence or absence of antibodies in a person is judged on the presence or absence of a particular disease. That is, a positive HIV test result indicates that this virus is present in your blood.

Could this be a mistake?

Although the possibility of error cannot be ruled out, modern diagnostic methods are very accurate and reliable. A lot of attention is paid to blood testing for HIV, and doctors' efforts are aimed at eliminating erroneous results.

In our AIDS Center you can discuss with an equal consultant your questions on Monday from 16 to 20 hours, on Tuesday from 9 to 12 hours or on Wednesday from 16 to 20 hours (office number 2). Information on support and self-help groups is listed below.

How will my life go now?

A newcomer with HIV-positive status has to get used to changes in their life. He now needs to regularly visit an infectious disease doctor at the AIDS Center, take tests and receive treatment. When a person starts taking ART, they should develop the habit of taking pills on time and not skipping medications. Particular attention is also paid to precautions that are designed to protect the patient himself and those with whom he contacts from possible transmission of HIV. So, for example, HIV-positive people need to be careful about sunbathing in the sun, try to avoid stress of any nature and have to give up some food products that are now contraindicated for them. A condom must be used for sexual intercourse. If an HIV-positive person needs medical attention, in case a doctor or other medical worker has to come into contact with the patient's blood (such as during operations), the doctor should be informed about the HIV-positive status. You can read more about measures to prevent HIV transmission in other sections of our website. These are the main features of living with HIV. Otherwise, life with HIV is the same in quality and duration as living without the virus. HIV-positive people have equal rights and opportunities with other people, they can start a family with any partner, give birth and raise children, live a full and long life, provided they receive the necessary treatment.

Support and self-help groups for people living with HIV:

1. Group for PLHIV (general)

weekly on Thursdays from 19.30

AIDS Foundation for PLHIV "AIDS.CENTER"

Moscow, st. Nizhnyaya Syromyatnicheskaya, 11, building 1, office 13 Kurskaya metro station

tel. +7 925 732 81 37, + 7 969 118 49 34

2. Group for HIV-positive MSM

weekly on Tuesdays from 19.30

LaSky project

Moscow, st. Myasnitskaya, 46/2, building 1, office 325 m. Red Gate

Testing for HIV positive is not a sentence. An anonymous HIV test result can be false positive for many reasons. The methods available to medical specialists make it possible to determine with 100% certainty whether HIV is absent or present in the human body. But there are factors that influence the distortion of the result.

The main ones are:

• doctor's mistake;
• home test;
• some pathological processes in the body.

Therefore, the data obtained must be rechecked, and it may turn out that the analysis results were incorrect.

Home test results for immunodeficiency virus

In public hospitals and private clinics, testing for the presence of the immunodeficiency virus is carried out anonymously. All data obtained as a result of the analysis is strictly confidential. Despite this, many do not get tested for HIV in medical institutions, fearing the spread of unwanted information.

Therefore, people prefer to carry out the analysis at home, buying tests from pharmacies. The presence in the body of the immunodeficiency virus in the human body will show a home test by two bright stripes. But often, a positive HIV test done at home is wrong. And the person, being not infected, gets a false positive result.

A positive test result for the presence of HIV in the patient's blood, which was carried out at home, will not be a basis for diagnosing a formidable disease. It must be remembered that several studies are needed to accurately diagnose HIV. Such analyzes are carried out only under laboratory conditions. However, if the home gives a positive indicator, then you should not delay the visit to the doctor. Laboratory tests can either confirm or disprove the results of a home test.

What to do if your home HIV test shows two stripes:

• consult a doctor (therapist or immunologist);
• undergo initial examination and tests;
• if necessary, do additional research.

You need to understand that if there is no desire to visit a doctor for such an unpleasant reason, you can take tests in the laboratory without a doctor's referral. In the state budgetary hospital, HIV testing is carried out free of charge, in private clinics - on a paid basis.

A study for the presence of human immunodeficiency virus in the blood for the purpose of diagnosis and further treatment can be carried out only in a medical institution. This significantly reduces the risk of distortion of the analysis results, which is less than 0.01%.

Causes of a false positive HIV test result in a laboratory setting

After receiving laboratory data and decoding them, a person can find out the result, which can be positive or negative. Even in cases where there is no promiscuous sex life and an asocial lifestyle (alcohol abuse or drug use), there are often cases of false positive results.

There are many factors that can affect the result of an HIV test and distort it:

1. Pregnancy condition.
2. Hormonal disruptions, including premenstrual syndrome.
3. Some pathological processes.
4. Vaccinations.
5. Surgical interventions, organ transplants.

Various reactions of the body, for example, allergic reactions, can lead to erroneous data. In the course of the study, the antigens produced can be perceived by the body as foreign. It happens that with allergies, antibodies are released that are structurally similar to those produced in HIV. Therefore, the data is sometimes obtained false positive.

In pregnant women, a change in hormonal levels is observed, which can also act as a factor distorting the indicators. The same goes for premenstrual syndrome and the period of menstrual bleeding.

Diseases that can affect the result:

• hepatitis;
• flu;
• herpes;
• tuberculosis;

• sclerosis;
• arthritis;
• fever;
• oncological pathologies;
• autoimmune diseases;
• venereal diseases;
• renal pathologies: malignant formations, urolithiasis, pyelonephritis;
• disturbance in the work of the liver and intestines, changes in the enzyme composition of the blood.

If the blood has poor clotting ability or is too thick, the indicator may also be skewed. It is not uncommon for donors who donate blood frequently and have not gone through the recovery period to have false positive results.

Medical workers cannot diagnose HIV in a person based on the results of one test, even if its result is positive, since there are cases when the indicators are overestimated for various reasons. All people who have received a "+" after the procedure undergo it again.

Medical error

It is not uncommon for a person to undergo a study in a special clinic, but receive a false positive result for HIV as a result of medical errors or negligence of medical personnel.

A false positive analysis can result from:

• incorrect blood sampling;
• non-compliance with the rules for storing biomaterial;
• low quality serum used for research;
• violation of the rules for transporting blood.

All these reasons can be combined into one big group - the negligence and incompetence of the medical staff. We can say that most clinics have the latest equipment, so the risk of receiving a distorted analysis is extremely small.

However, this possibility is not completely ruled out. Thus, if a positive test result is obtained for the presence of this terrible ailment, it is better to re-analyze.

Be aware that a person can have a false positive HIV test result. With subsequent examinations, the wrong diagnosis may be removed. However, in order for the analysis data not to be distorted, a person must inform the doctor in advance about concomitant diseases or pathological conditions. You also need to say about the medications used during the study.

It is stressful for any person to do research for infection with the immunodeficiency virus. And all people who receive a transcript of negative HIV test results breathe a sigh of relief. However, such a result is not always reliable, and, quite often, the absence of a positive answer does not mean that a person is completely healthy.

Let's consider what the result of HIV testing is negative, and what errors may arise during the research.

The annual increase in the number of HIV infections raises an urgent need for reliable diagnosis of the HIV virus. For this, any large city has the Centers for the Prevention and Control of AIDS, in which the analysis for this infection is done absolutely free and anonymously. The examination can be transcribed in 5-10 days.

The results of blood testing for this ailment are commonly called:

• positive - HIV is detected;
• negative - no immunodeficiency virus;
• questionable or undetectable.

What does HIV-negative reaction mean in different types of blood tests:

1. Initial diagnosis of virus infection is carried out. An enzyme immunoassay detects the presence of antibodies in a patient. A negative test result indicates that human biomaterials do not contain specific response cells produced by the human immune system when it is infected.
2. The most reliable and expensive method to use is immunoblotting. It is not used routinely to diagnose HIV, but it is prescribed when ELISA results are in doubt. The percentage probability of getting a reliable answer is 98%. The remaining 2% accounted for errors caused by disruptions in the work of medical personnel.
3. rarely performed in adults. Usually it is used to diagnose HIV infection in a newborn baby directly during childbirth or during intrauterine stay. PCR can show the presence of HIV DNA and RNA immediately after infection. After carrying out a study by the polymerase chain reaction method, a person receives a result, which will indicate the number of detected RNA strands of the virus. This factor is called viral load. If the amount of RNA is less than 20, then the result can be considered reliably negative.
4. They have recently appeared on the shelves of pharmacies. They are test strips coated with a diagnostic serum. The accuracy of such a study is only 80%. Therefore, in case of a negative response from the home test system and after contact with an infected person with this infection, it is necessary in any case to contact the Center for the Prevention and Control of AIDS for more accurate examination methods - enzyme immunoassay or immune blotting.

If there is no doubt about the negative answer, but there was still contact with the infected person or the contact continues, then it would be advisable to contact the AIDS Center for advice about it. It consists in taking antiretroviral drugs to exclude possible infection.

Are diagnostic errors possible?

There is such a thing as the development of an infection. This is the time period when the body is just beginning to fight the infection that has got into it, and the concentration of antibodies in the blood is still negligible. This period lasts on average 14 to 60 days after infection. If you take a blood test for HIV during this period, it will be negative. For some people, it may take only a few months to begin, in which case it is called the "window period" and can last up to a year and a half.

Reasons why AIDS testing can be false negative:

1. An atypical immune response that can occur in the presence of other inflammatory diseases in a person.
2. Conditions after organ transplant. After transplantation, a person is prescribed strong immunosuppressive (immunosuppressive) drugs that block the formation of antibodies to the virus.
3. Seronegative variant of the course of this viral infection. In this case, there is a long incubation period after the moment of infection, and antibodies to the virus begin to be produced much later than average. The infection may not be detected in the blood for several months.
4. With the latter (or terminal). At the same time, the state of the immune system is so strongly depressed that it no longer has the strength to develop a response to the presence of infection.
5. Violations of the collection of biomaterial, its transportation and storage. It also includes violations in the use of diagnostic sera by medical personnel.

If the test response to HIV is negative and no antibodies to infection are found, then you still need to consult your doctor about this. If a specialist has doubts when studying the results of the examination, then the diagnosis of blood for HIV can be repeated after 3 months.

The following factors speak for the reliability of the research results:

• all the terms of the diagnosis have been met;
• the collection, transportation and the process of researching the biomaterial itself are performed correctly;
• the person did not drink alcohol, carbonated drinks, fried, fatty, spicy or salty foods.

If all the rules are followed, and the doctor did not suspect even the slightest signs of infection with the immunodeficiency virus, then the received negative response can be considered 100% reliable.

Special attention is currently paid to the diagnosis of HIV (immunodeficiency virus) in humans. Detection of the disease at an early stage will help to start the treatment course earlier and this will significantly affect the increase in the patient's life.

After the test for HIV has been passed, the decoding of the results, as a rule, is positive or negative. At the same time, there is a primary diagnosis and a secondary one. With the primary - the person is checked using ELISA. If necessary, a second blood test for HIV is done. What does positive and negative result mean? How is the transcript of an HIV test done? Why does a person who is not a drug addict and alcoholic have a permanent sexual partner, deciphering the analysis for the immunodeficiency virus gives a positive, but questionable result?

About HIV

The causative agents of the disease are of the 1st and 2nd type. For a long period of time, their presence in humans goes unnoticed, then immunity is affected first of all, then other human systems.

With the main method of laboratory diagnosis of the immunodeficiency virus, antibodies to HIV are detected. The enzyme-linked immunosorbent assay (ELISA) is the basis of the method, it is sensitive (99.5% and higher) and specific (99.8% and higher). In addition, when diagnosing HIV using ELISA, the p24 antigen is determined.

Each test system has different indicators, in connection with this, they determine the various protein structures of the viral envelopes. The causative agents of HIV are of two subtypes: 1st and 2nd or HIV-1 and HIV-2. Viral particles look like a spherical shape with an outer phospholipid membrane. For the 1st subtype, it has the following molecular weight: gp120, gp41, gp160. The 2nd subtype contains gp105, gp36, gp140. For the inner envelope of the virus, the molecular weight is also known. For the 1st subtype, these are p55, p17, p24. For the 2nd - p16, p25, p55.

There are three main sets of proteins for each test system to identify a virus.

In general, the ELISA result can be:

• negative;
• false positive;
• false negative;
• dubious or vague.

Antigens and antibodies are detected by diagnostic methods.

About a normal result

Norm - what does it mean? When an HIV test is negative, this is considered normal.

1. The latest generation of ELISA test systems can determine the presence of antibodies to HIV and protein particles. If the analysis is normal, then no antibodies and protein particles of the pathogen are found in the blood. But it is possible to say for sure that a person is healthy on the basis of this, if there was no risk of infection for 3 months before his delivery. Otherwise, once again, after a while, it is necessary to repeat the tests.

There have been cases that HIV was detected only after 6 months. Therefore, if the result is negative, and there was contact with an HIV-infected patient, for reliability it is necessary to repeat the tests after three, four and six months. It happens that the ELISA gave a negative result, and the person clearly has a suspicion of the presence of signs of HIV, it is recommended to take the test again. An erroneous result is possible due to the early timing of the analysis or due to human factors.

2. If a negative result is obtained by immunoblot, then at present this is the most reliable analysis.

If a person has an immunodeficiency virus, and the result is negative, then most likely this is a medical error that can occur at any stage of the test. If, when repeating the immunoblot after three and six months, the result is negative, then there is nothing to worry about, this indicates the norm. And only after a negative immunoblot response, a certificate will be issued that the HIV test is negative.

3. PCR research in adults when diagnosing the immunodeficiency virus is used extremely rarely, and this method is used for newly born children.

A negative result is also considered the norm here.

4. According to sociological research, many people use a rapid HIV test. At the sight of a negative strip, people calm down and refuse to go to a medical facility, even if they have all the signs of HIV infection. But you need to know that the accuracy of the express test is eighty-five percent. In addition, at home, you can incorrectly conduct it, or the conditions for its storage will be violated. It is even more likely that the result is incorrect. Even ingestion 8 hours before testing alkaline mineral water will affect the test result. Therefore, the fact that the immunodeficiency virus is absent in humans on the basis of an express test, even if it is negative, is far from always a true statement.

Decoding analysis

After testing has been carried out in people, the question often arises of how to decipher the result of the research, what to do if a positive result for HIV is obtained.

1. If the ELISA showed the presence of all or almost all antibodies to antigens according to this test system, this means a positive test for HIV. If the response after the second serological enzyme immunoassay is positive, then an immunoblot should be performed. Deciphering its results will be more correct. If the enzyme immunoassay gave a positive result, the next immunoblot analysis also showed the presence of HIV, then the final result is put. When the tests are deciphered, then you need to know that a positive HIV test is determined:

• 60% to 65% 28 days after infection;
• 80% - after 42 days;
• in 90% - after 56 days;
• 95% - after 84 days.

If the response to HIV is positive, then this will mean that antibodies to the virus have been detected. To avoid a false positive answer, it is necessary to pass the tests again, preferably twice. If antibodies to immunodeficiency are detected when passing two tests out of two, or when passing 3 tests in 2 of them, then the result is considered positive.

The p24 antigen can be detected in the blood as early as 14 days from the day of infection. Using the enzyme immunoassay method, this antigen is detected from 14 to 56 days. After 60 days, it is no longer in the blood. It is only when AIDS forms in the body that this p24 protein grows again in the blood. Therefore, enzyme immunoassay test systems are used to detect HIV in the early days of infection, or to determine how the disease is progressing and to monitor the treatment process. The high analytical sensitivity of the enzyme-linked immunosorbent assay detects p24 antigen in biological material with HIV of the first subtype at a concentration of 5 to 10 pg / ml, with HIV of the second subtype from 0.5 ng / ml or less.

2. A dubious result of an enzyme-linked immunosorbent assay means that the diagnosis was made somewhere, as a rule, medical workers confused something, or the person has signs of infection, and the result is negative, which raises suspicion, the person is sent for a second test.

3. A false positive result is understood as a result when blood tests were performed under the following conditions of the patient:

• pregnancy;
• if a person has a hormonal disorder;
• with prolonged immunosuppression.

How to decipher the analysis in this case? A false positive result is given if at least one protein is detected.

Due to the fact that the p24 antigen is very dependent on individual variations, using this method, in the first period of infection, from 20% to 30% of patients are detected.

About indicators after research by the method of polymerase chain reaction

Using this method, HIV RNA and DNA are detected almost immediately after infection. But the final diagnosis is not made, it requires mandatory confirmation by other methods. "Help decipher the PCR result." - quite often you can hear such a request. What is written in this case if an immunodeficiency virus is found? When responding to the result of an analysis made using PCR, the number of copies of RNA in a milliliter of blood is indicated. The table below shows the result depending on the quantitative characteristics in the blood.

It is good to use the above table when testing for AIDS, as it can easily determine the stage of the disease.

These tables, taking into account various test systems, are in laboratory rooms for each method of enzyme immunoassay and immunoblotting.

Often asked: "Decipher the answer after the study by the method of polymerase chain reaction in terms of CD4." The normal number of CD4 cells is from 600 to 1900 cells per milliliter of biological material. This corresponds to HIV negative status. But you need to know that these indicators, even in healthy people, are not in this range.

In the modern world, many laboratories already have good equipment with which it is possible to fully examine the body for the content of HIV infection in it.

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