Kidney transplantation is a surgery that replaces the function of critically ill kidneys by transplanting a healthy kidney from another individual called a donor.
The main functions of the kidneys are: to control the volumes and composition of fluids in the body and to eliminate harmful substances produced by the metabolism.
The extent of renal function is measurable with formulas that estimate the blood filtration capacity of the kidneys; it is defined as "glomerular filtration rate"(In acronym GFR which stands for" glomerular filtration rate "), and is expressed in milliliters (ml, thousandth of a liter) of blood purified in one minute (min).
When the kidneys are functioning normally, the glomerular filtration rate (GFR) is between 90 and 120 mL / min. Below 90ml / min. we speak of renal failure.
Generally, a distinction is made between:
- acute renal failure, due to sudden damage to the kidneys, organic or functional, which in some cases may be reversible with appropriate treatment
- chronic renal failure, progressive decay of renal function that can be caused by the evolution of acute renal failure or, as more commonly happens, by a wide range of slow-developing (chronic) nephropathies
When the kidneys permanently and irreversibly lose their functions, as occurs in chronic renal failure, fluids are no longer filtered and disposed of to the extent necessary and waste products accumulate, with serious damage to the whole organism.If renal function falls below a threshold, assessed as 15 ml / min of GFR, it becomes incompatible with life.
The severe and irreversible loss of kidney function, known as end stage renal failure or "chronic uremia", Can be replaced with an" artificial "blood filtering procedure, hemodialysis; however, this type of treatment is partial and can be uncomfortable and disabling for the patient who undergoes it. For this reason, when possible, kidney transplantation is the first choice treatment in case of end-stage renal failure (Video).
The conditions necessary to undergo a kidney transplant
Most people who need a kidney transplant can have this operation regardless of their age as long as:
- their physical condition is good enough to withstand the effects of general anesthesia and surgery
- the patient is willing to follow the treatments indicated after the transplant (for example, taking anti-rejection drugs, the so-called immunosuppressants) and undergo the program of check-ups following the surgery
- the transplant has a high chance of success
Reasons why a transplant may not be safe, or effective, include having an "ongoing infection (which requires pre-treatment), severe heart problems, cancer, or known acquired immunodeficiency syndrome (AIDS)." .
Unlike other types of organ donations, it is possible to donate a kidney even while living because only one kidney ensures adequate function to allow you to have normal health conditions.
People who want to be considered as kidney donors are analyzed very carefully both from a physical and psychological point of view to exclude that the donation of the kidney could cause damage to the donor himself or to the patient who must receive it and that the will to give is free from conditioning and aware. In the greatest number of cases, living donations come from close relatives because they are more likely to have genetic characteristics and blood group compatible with the patient and this reduces the risk of rejection. In any case, the assessment of the suitability of the donor as a living is always a complex and scrupulous process, it is supported by an independent commission of experts, called "third party" and is validated by a magistrate.
Kidney donations are also possible from people who have died as a result of direct damage to the brain (the so-called "brain death") as long as the donor has expressed in life (in writing or verbally to family members) the will to donate organs after death or, if he has not expressed it, if the family members do not object. This type of donation is known as "cadaver kidney donation", since the organ harvesting can only be performed after the ascertainment of death, which takes place with a carefully defined procedure and in a short time to ensure that the organs to be transplanted remain functioning.
The transplant from a living donor, on the other hand, being carried out with an organ coming from a person in perfect health and with a procedure that allows to minimize the ischemic damage associated with the kidney removal operation, has a greater chance of success. long term, compared to that of a deceased donor, and is currently the most effective therapeutic choice for the treatment of end-stage renal failure.
People who need a kidney transplant, but do not have a suitable living donor, will have to wait until a compatible kidney from a deceased donor becomes available. For this there are waiting lists (read the Hoax).
On the basis of rules issued by the National Transplant Center, each center that performs transplants has the task of assessing the suitability of candidates who belong to their own transplant program and of taking care of their registration and updating on the waiting list. For pediatric patients there is a national waiting list, while for adults (over 18 years of age) there are, except for special cases such as clinical emergencies and some specifically defined conditions, regional or interregional lists, managed by a single center reference.
The application for registration must necessarily go through a transplant center which may be different from that of the region of residence. The necessary personal, clinical and immunological data are required for each patient. The immunological evaluation is carried out by specialized laboratories accredited by the National Transplant Center. In Italy, on average, waiting times for a kidney transplant from a deceased donor 3 years 3 months for the standard list, 1 and 7 months for the list of Urgencies, as well as for the pediatric list, 2 years and 4 months for the list of hyperimmune patients.
During 2020, 2,843 of the 7,941 patients on the waiting list as of December 31, 2019 left the list: 1,623 for transplant, 239 for death and 980 because suspended due to inability, temporary or definitive. In the same period, 2,326 patients were included in the list for which, as of 31 December 2020, 7,424 patients were on the active list for kidney transplantation.
If a patient has undergone an unsuccessful transplant, he can be re-enrolled in the waiting list for another transplant and while waiting to undergo the new surgery he will have to undergo dialysis.
The transplant procedure
When you get a kidney from a living donor, it is a carefully planned operation. If, on the other hand, you are expecting a deceased donor kidney, the transplant center will contact the person to be transplanted as soon as a suitable kidney is available. This can happen at any time of the day or night. The medical staff will check that there is no new medical problem, will contact the patient asking him to go to the center where the final checks will be carried out to be sure that the transplant operation can be performed. After these checks, surgery is carried out to transplant the kidney and connect it to the blood vessels and bladder. The new kidney is placed in the lower abdomen, while the non-functioning kidney is generally left in place.
A kidney transplant is a delicate surgical operation with a wide range of potential risks. In the short term they include surgical complications and infections. Long-term problems, which include diabetes and an increased risk of infections and cancer, are generally related to the medications the transplant patient needs to take to reduce the chances of rejection. For this, regular checkups are required for the rest of life after a kidney transplant.
Having a healthy lifestyle after a kidney transplant is the best way to minimize the risk of complications.
Hence, it is recommended to:
- stop smokingif you are a smoker
- eat healthy foods
- lose weightif you are overweight or obese
- take precautions to avoid infections, such as not going to closed and crowded or hygienically unhealthy environments
- exercise regularly to keep the whole body, and therefore also the transplanted organ, in good condition for as long as possible
There are a large number of factors that affect the lifespan of a transplanted kidney. The most important are the origin of the transplanted kidney (whether from a living or deceased donor), immunological compatibility, age and general state of health of the patient awaiting a transplant.
The National Transplant Center collects data on the results (outcomes) of transplants of each individual center on the Transplant Information System and publishes every year updates on the quality of transplant results in Italy, in terms of organ and transplant survival.
On the basis of the data currently available, the average survival of a kidney transplant in Italy is 95% one year after surgery and decreases to 90% after five years and to 75% after 10 years. The data relating to each individual center are published on the website www.trapianti.salute.gov.it
NHS Choices. Kidney transplant (English)
Mayo Clinic. Kidney transplant (English)