Kidney transplantation( kidney transplantation) - Causes, symptoms and treatment. MF.

Kidney transplantation is by far the most effective method for treating the terminal stage of chronic renal failure. In addition, the costs for each patient who underwent renal transplantation are significantly lower compared to the cost of treating a patient on hemodialysis and peritoneal dialysis. The annual increase in patients with the final stage of chronic renal insufficiency, according to data from countries such as Japan, the United States, is 230-300 people per 1 million inhabitants. Therefore, the problem of the availability of those infected with donor organs is particularly acute. Currently, many legal and ethical-ethical issues of transplantation of human organs remain unresolved.

The legal aspects of organ and tissue transplantation are set out in the "Body of Fundamental Principles on Human Organ Transplantation" approved at the 44th session of WHO in 1991 and the "Convention on the Protection of Human Rights and Dignity of the Person in Connection with the Use of Biology and Medicine", which entered into forceJanuary 24, 2002 in Strasbourg.

The key to the problem of organ and tissue transplantation is the principle of legality. At the same time, there are two main legal models protecting the rights of the cadaver donor. This "presumption of consent", or the French model, and the "informed consent system" - the American-Canadian model. According to the "presumption of consent", the ban on the removal of organs after the detection of clinical death extends only to persons who, during life, verbally or in writing, have confirmed their refusal to remove organs. It is also legal to ban the next of kin of the deceased from using it as a cadaver donor. That is, on the basis of the French model, consent to organ harvesting is considered "by default" until a refusal is received.

In contrast, in the "informed consent system", removal of organs is performed only with the written consent of the donor, and also if the relatives also expressed their consent after his death.

Both legal models of organ transplantation are common in the modern world, and the presumption of consent is valid in Belgium, France, Austria, Poland, Latvia, Finland, Estonia, Lithuania, Russia and Belarus. Informed consent is mandatory in the UK, USA, Canada, Holland, Switzerland, Germany. In any case, before the removal of organs, doctors are obliged to inform the relatives of the deceased about the possibility of carrying out this operation, and to perform the operation only if they agree. However, Swedish laws allow for "minor" seizures of organs and tissues, such as the pituitary gland, the cornea, without the consent of the deceased or his relatives.

First you need to decide on the basic concepts in transplantology. Donor - a person whose organ or tissue is transplanted to another person. A recipient is a person receiving an organ or tissue from a donor. A graft is an organ or tissue that the donor receives from the recipient. Sensitization - a special sensitivity of the body to foreign substances, leading to the development of a number of allergic reactions.

Preparing for kidney transplantation

When planning kidney transplantation, it is very important to consider the immunological aspects of this method of treatment. First, the compatibility of the donor and recipient directly affects the efficiency of the transplant. Secondly, the low compatibility of the organ helps to increase the sensitization of the donor, which in repeated transplantations leads to more frequent organ rejection. To assess the compatibility of organs, HLA molecules( human leukocyte antigens) are determined, which in the human body are represented by the MHC( major histocompatibility complex).These indicators determine both the donor and the recipient. In the case of insufficient compatibility of the transplant after transplantation, reactions of rejection develop.

The following types of rejection reaction are distinguished:

• hyperactive rejection - develops 1 hour after transplantation. It is associated with damage to the donor kidney by the already existing antibodies in the body of the recipient. These antibodies, as a rule, are formed due to previous unsuccessful transplantation, pregnancy or blood transfusion.

• acute rejection occurs 5-21 days after kidney transplantation. This reaction is due to the fact that, in response to ingestion of the transplant, antibodies are developed that are designed to protect the body from an alien organ. These antibodies cause death of the graft.

• chronic rejection occurs in the long term. The cause of it can be an infection, or an incompletely cured reaction of acute rejection.

One of the main methods for determining the compatibility of the donor recipient is to conduct a direct cross-match. With this test, pre-existing potentially dangerous antibodies are detected in the recipient's serum, which can damage the transplant. As a monitoring, patients waiting for kidney transplantation should provide blood to the laboratory every three months to identify dangerous antibodies that can be formed, for example, after a blood transfusion. When a donor appears, a cross-match test is performed.

After transplantation, a cross-match test is also performed, which becomes positive in case of rejection of the graft. Antibodies to the transplant are determined at 1,2 and 4 weeks after transplantation, then every 3 months.

All donors are divided into 2 types - living and cadaver. Live donors are people who voluntarily donate an organ or part of an organ for transplantation. Cadaver donors are deceased donors, whose organs are removed in a timely manner.

Transplantation from a live donor has several advantages:

1. The results of the operation are better, since the organs of the living donor are more compatible with the recipient organism. In this regard, after transplantation, a more sparing immunosuppressive( suppressing immune response) therapy is used.

2. The presence of a live donor allows to reduce the time of the recipient's presence on dialysis. In some cases, pre-dialysis transplantation takes place, that is, shortly after confirmation of the diagnosis, terminal renal failure. In addition, organ transplantation from a living donor is usually a planned operation, which allows maintaining a high quality of life of the recipient.

Conducting a kidney transplant

First of all, it is important to carry out compatibility tests when selecting a donor. In the case of positive results, a comprehensive donor survey is conducted to identify contraindications. Kidney donation is contraindicated:

• with diseases of the urinary system;
• Severe decompensated diseases of the cardiovascular system;
• malignant neoplasms of any site;
• diabetes mellitus;
• thromboembolic disease;
• alcoholism, systemic and mental illness.

For kidney donation, it is necessary that the remaining kidney be absolutely healthy. Therefore, the organs of the donor's urinary system should be carefully examined.

Removal of the donor kidney is an important and dangerous operation. The risks associated with this operation are divided into two parts:

• early, associated with surgery and an early postoperative period.
• Late, associated with further life in the absence of a kidney.

When studying the late risk of donors, scientists conducted one large study. Two groups of people were evaluated. The control group included persons who, due to trauma or neoplasm, had a kidney removed. The test group consisted of living donors of the kidney after successful removal of the organ. Twenty years after the removal of the kidney, scientists analyzed the causes of death and the quality of life of patients. It turned out that there was practically no difference between the control group and the study group. This allowed the authors to name their research "The kidney donation prolongs life."

The operation of kidney removal from donors is carried out, as a rule, by an open method.

Fragment of kidney removal from the donor.

In the postoperative period, early activation of the donor is indicated, prevention of thromboembolic complications.

Dead bodies from craniocerebral trauma, strokes, ruptures of cerebral aneurysms, as well as neoplasms of the brain without metastasis become cadaveric donors. In the presence of known renal diseases, age over 65, HIV infection, hepatitis B and C viruses, bacterial sepsis, donation is contraindicated. The removal of the organ is carried out only after the death of the brain is ascertained.

After seizure prior to transfer to the recipient organism, the kidney is in a state of ischemia( lack of nutrition and oxygen).Therefore, it is necessary to carry out a number of measures aimed at maintaining the vital functions of the body. These measures include the longest possible maintenance of the normal functioning of the donor's organism, preservation of the removed kidney in a special environment, and as soon as possible the operation to the recipient.

Container for storage of transplant.

After kidney transplantation

After operation for a week, the recipient is in the intensive care unit, where permanent monitoring of vital signs is provided. Under favorable conditions, he spends some time in the clinic, then goes to an outpatient treatment under the supervision of a nephrologist. At the same time, compatibility tests, evaluation of the transplant function are carried out regularly.

To suppress the formation of antibodies to the transplant, immunosuppressive therapy is used. It includes cytostatics( Sandimmun, Tacrolimus), preparations of microfenic acid( Mayfortic), as well as hormonal drugs( methylprednisolone) according to a certain scheme. If necessary, antibacterial and antifungal agents can be used.

Kidney transplantation contributes to the survival and improvement of the quality of life of patients with terminal stage of renal failure. American scientists found that the risk of death in recipients after surgery compared with patients on dialysis and waiting for transplantation is higher only for 100 days after the operation. After this time, the risk of death is reduced by almost half. Therefore, currently, of all types of renal replacement therapy, kidney transplantation is becoming the most priority.

Physician therapist, nephrologist Sirotkina EV