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Treatment of HIV infection is a complex, multifaceted and responsible process that requires a serious attitude. Moreover, the success of therapy depends on the efforts of not only the doctor, but also the patient. A positive effect can be achieved only if a large number of conditions are met. Both the doctor and the patient must know and clearly follow them.
The Russian Federation is a country that has impressive experience in the treatment of HIV infection. The basis is antiretroviral therapy (ARVT or HAART), thanks to which HIV infection has ceased to mean a death sentence. Now this disease is considered as chronic. With the help of antiretroviral therapy, the virus cannot be eliminated from the body, however, it is possible that such an opportunity will appear in the foreseeable future.
Reception of antiretroviral devices is carried out to achieve the following goals:
virological target. It is aimed at stopping the reproduction of viral cells in the human body. The successful achievement of the goal can be judged by the viral load in the blood. If it is at an undetectable level, then the virological goal is considered achieved;
immunological target. It is aimed at improving the immune status of the patient. When the viral load decreases, and ideally becomes undetectable, the number of CD4 lymphocytes in the blood begins to increase. They are responsible for the body’s immune response to any infection. It is important that the patient understands that taking antiretrovirals does not directly increase the CD4 count;
clinical purpose. It is aimed at preventing the development of diseases that accompany AIDS. That is, the main thing in achieving this goal is to allow the body to fight HIV infection and prevent the development of AIDS, and hence diseases that could lead to death.
Treatment of HIV infection with antiretroviral drugs is based on the following principles:
Early initiation of therapy (it should be started when CD4 falls below 350 µl);
Regular intake of drugs;
Adherence to HIV treatment.
If a doctor suggests that a patient start antiretroviral therapy, the suggestion should not be rejected. Moreover, if the patient wants to achieve the effect of treatment, he must strictly follow all the recommendations of the treating doctor. Only in this way does a person have the opportunity to live a full and long life. At the same time, the quality of life of an HIV-infected person will practically not differ in any way from the quality of life of healthy people.
In order not to miss the moment from which it is necessary to start antiretroviral therapy, the patient should be regularly examined at the AIDS Center. The fact is that without special tests it is almost impossible to detect the symptoms of HIV infection. This virus destroys the immune system slowly but steadily. Therefore, you can not wait for any subjective symptoms for many years. Meanwhile, time will be lost.
Three factors will indicate that it is necessary to start treatment for HIV infection:
The number of CD4 cells reflecting the state of the patient’s immune status;
The number of viral cells in the blood, reflecting an indicator such as viral load;
The presence of diseases caused by HIV infection. These diseases are called “opportunistic”. If they are diagnosed in a person, then therapy begins regardless of his immune status or viral load.
To determine the amount of virus in the blood, doctors conduct special tests. They give the result in the numerical number of copies of the virus in one ml of blood. The higher the CD4 count, the stronger the person’s immunity. In addition, in the laboratory determine the percentage of CD4 lymphocytes (CD4%). However, when prescribing therapy, doctors start from the absolute, and not from the relative number of cells. That is, from the number of cells in a liter of blood, and not from their percentage ratio.
The Ministry of Health of the Russian Federation recommends starting antiretroviral therapy when the CD4 cell count begins to fluctuate in the range of 200-350 cells/mm3, and the viral load exceeds 100 copies/ml.
It should be borne in mind that the level of CD4 is a variable value. It depends on a huge number of factors, including alcohol intake, smoking, emotional upheavals, other infectious diseases, negative environmental conditions, etc. Therefore, it is not advisable to start treating HIV infection based solely on one indicator. The doctor must track the dynamics of the CD4 level over several months and correlate the results with factors that could affect the state of the person’s immunity.
The risk of developing opportunistic diseases increases with a CD4 count of less than 300 cells/mm3, as immune defenses are weakened. The patient may develop infections associated with diarrhea, dehydration, weight loss.
Pneumocystis pneumonia is a disease that occurs in the majority of HIV-infected people whose CD4 count is below the threshold of 200 cells/mm3. If this indicator falls below 100 cells / mm3, then the risk of developing serious infectious diseases becomes very high.
This does not mean 100% that an infection will definitely occur, but people with this CD4 count are at significant risk to their health. Moreover, drugs aimed at treating opportunistic infections often cause much more harm to health than taking antiretroviral therapy.
Naturally, the prospect of starting antiretroviral therapy worries patients, but it should be understood that without proper treatment, HIV infection remains a deadly disease. Therefore, it is necessary to start treatment in a timely manner so that it is not too late. Indeed, with a CD4 count of less than 200 cells / mm3, deadly diseases can manifest at any time.
Therefore, regular scheduled visits to the doctor and strict adherence to his instructions are a necessity that ensures the safety of life. When a doctor does not prescribe treatment for HIV infection, this does not mean that it is no longer necessary to appear at the AIDS Center. It is important to monitor the state of your immunity at least once a year, and sometimes more often (once every 1 months or once every 6 months). During a visit to the doctor, he will definitely inform the patient when he needs to come next time.
In addition, people with HIV infection should, as necessary, be observed by other specialists (oculist, otolaryngologist, neuropathologist, gynecologist, etc.), as well as undergo diagnostic procedures (lung x-ray, ultrasound, ECG, etc.).
A person’s adherence to HIV treatment
A person’s adherence to HIV treatment is a concept that defines the extent to which a patient is involved or involved in their therapy. An adherent is a patient who seeks to receive treatment, shows an interest in his own health, and the decision to start antiretroviral therapy is made by the patient based on the knowledge gained in the process of consulting with a competent infectious disease specialist.
The goal of adherence is to regularly take antiretroviral therapy and achieve a stable therapeutic effect. To assess the degree of adherence, you can count the number of drugs taken or procedures completed. As a result, the percentage of completed medical appointments will indicate the indicator of adherence.
The effectiveness of HIV treatment directly depends on the patient’s adherence to therapy. The higher the commitment, the higher the likelihood of a positive outcome. The level of adherence depends on the specific disease. So, in the treatment of hypertension, 61% is considered a sufficient level of adherence. This percentage is usually sufficient for most chronic diseases. However, HIV infection stands out against their background. In order for antiretroviral therapy to have a positive effect, adherence to treatment should be at least 90-95%.
The need for such a high level of adherence is explained by the characteristics of the immunodeficiency virus, namely its ability to mutate. Each missed dose of antiretroviral drug creates conditions for the virus to quickly adapt to the therapy received and form resistant cells. Some drugs stop working at 4-6 mutations, and some at just one mutation. That is, sometimes a single dose skip is enough for the drug to lose its effectiveness for a particular patient. The virus will be able to multiply, despite the ongoing therapy.
Another pressing problem is the transfer of therapy-resistant strains of the immunodeficiency virus from one person to another. As a result, the infected person develops primary resistance, that is, initially a person becomes infected with a resistant strain of the virus. For example, in the countries of the European Union, there are already more than 10% of such infected people from the total number of HIV-positive people, and this figure is constantly increasing.
The more resistant strains of the immunodeficiency virus spread, the more expensive the therapy becomes, which means that the survival rate of patients decreases.
The two main threats to low adherence to antiretroviral therapy are:
Increasing the cost of drugs, reducing the effectiveness of the treatment received;
An increase in the number of people infected with resistant strains of the virus.
HIV treatment and the emergence of resistance
The immunodeficiency virus, on the one hand, hides in those cells where it is difficult for drugs to penetrate. There he can live for many years. Latent CD4 lymphocytes and dendritic follicular cells of lymphoid tissue act as such reservoirs.
On the other hand, the virus constantly mutates inside the human cell. This process of mutation is called replication. In the process of replication, the virus copies the genetic information that is contained in a specific sequence of nucleotides. It is this copied information that it then passes on to the next generation of viruses.
The virus has the ability to replicate information due to the presence of a protein called reverse transcriptase. This protein in the virus works with errors, making mistakes. That is, during the assembly of each new virus, from 5 to 10 mutations will occur (taking into account the fact that HIV has about 9000 nucleotide pairs). These mutations are most often fatal for the virus, as they deprive it of the possibility of further copying. But in some cases, the mutation changes the virus so much that it becomes able to survive even if it is exposed to an antiretroviral drug. Thus, the next batch of new viruses receives reliable protection and begins to reproduce new cells, protected from the harmful effects of drugs taken by humans. As a result, there is a loss of sensitivity of the virus to antiretroviral treatment.
If HIV mutates and acquires resistance to several drugs at the same time, then experts point to the occurrence of cross-resistance. The emergence of therapy-resistant strains significantly complicates the treatment of HIV-positive patients.
The emergence of HIV resistance
A person may initially be infected with an antiretroviral treatment-resistant strain of HIV. In this case, we are talking about primary resistance. For example, in North America, such a probability, according to various sources, ranges from 1 to 11%, and in the countries of the European Union – from 9 to 21%. The incidence of therapy-resistant strains is increasing every year. This is explained simply, because primary resistance is someone’s induced resistance to drugs. The second concept means that mutations arose in the body of a certain person with insufficient effectiveness of antiretroviral therapy against the background of a viral load.
The risks of developing resistance of virus strains largely depend on the correct effect of the drug on the patient’s body and on the effect of the patient’s body on the drug being taken. That is, the likelihood of developing resistance depends on the pharmacokinetics of the drug and on its pharmacodynamics.
Any antiretroviral drug must be taken at a given time interval so that it can be properly absorbed, enter the bloodstream and accumulate in the tissues at the required concentration. A wide variety of factors can have an impact on pharmacodynamics and pharmacokinetics, including the patient’s age, gender, meal times, genetic characteristics, concurrent use of other drugs, etc. All these factors must be taken into account when selecting an antiretroviral drug. If the patient does not comply with the dosage, takes the drug at the wrong time, or skips doses altogether, this can lead to resistance. Therefore, the high adherence of each infected person is the key to successful therapy, and hence the prevention of resistance.
Antiretroviral treatment for HIV should be selected only by a doctor, taking into account all possible factors that may affect the emergence of drug resistance in a particular patient. As necessary, the treatment regimen can be adjusted.
Resistance prevention in HIV treatment
Experts have found that if the level of copies of the virus in the blood is less than 50 and the load is undetectable, then the risk of developing resistance of HIV strains to antiretroviral treatment is very small.
In order to prevent HIV drug resistance, the following principles should be followed:
Regular monitoring of the viral load in the patient’s blood;
Strict adherence to medical recommendations. It is strictly forbidden to deviate from the scheme prescribed by the doctor. The antiretroviral drug must be taken at a specific time and dosage. The level of its absorption can be affected by diarrhea, vomiting, taking other medicines, diseases. It is important that the patient promptly informs the doctor about his problems;
Antiretroviral therapy started for the first time should be qualitatively selected. The risks of developing resistance directly depend on this;
Resistant strains of HIV can be re-infected. Sometimes two or more strains of the virus enter the human body (co-infection). For example, one in four infected people living in San Francisco has resistance to one or more antiretroviral drugs. To prevent this from happening, it is necessary to follow measures to prevent HIV transmission;
Getting new knowledge. A person with HIV infection must constantly replenish his knowledge base about his disease. The source of information can be the media, the attending doctor, popular and scientific literature. The deeper the patient delves into the essence of the problem, the more he has knowledge about the treatment of the disease, the higher the chances that he will not make mistakes that lead to resistance.
However, the basic protection against resistance currently remains an undetectable viral load.