Kidney transplantation (KT) is the outcome of great advancement in medical science.
Kidney transplantation is the treatment of choice for end-stage kidney disease (ESKD). Successful kidney transplantation may offer better quality of life and longer patient survival compared with dialysis. Life after successful kidney transplantation is almost normal.
Kidney transplantation is a surgical procedure in which a healthy kidney (from a living donor or deceased - cadaver donor) is placed into the body of a person suffering from end-stage kidney disease (recipient).
Kidney transplantation is necessary for patients who are suffering from ESKD who are on dialysis (haemodialysis or peritoneal dialysis) or who are approaching ESKD but not yet on dialysis (pre-emptive KT).
A patient with acute kidney injury should not undergo KT. Kidney transplantation is also not done in cases where only one kidney fails and the other kidney is still functioning. Transplantation should only be done if the renal failure is irreversible.
Dialysis replaces some degree of the filtration of waste products of the kidneys. Other functions of the kidneys are not accomplished, some of which are better addressed by transplantation. Hence, kidney transplantation, when a suitable donor is available and when no contraindications are present, offers the best treatment option for complete rehabilitation of a patient with end-stage kidney failure. As kidney transplantation saves lives and enables one to enjoy almost normal life, it is referred to as the “Gift of Life”.
Major benefits of successful KT are:
Kidney transplantation offers many benefits but also has disadvantages. These are:
Kidney transplantation is not recommended if the ESKD patient has:
Although there is no fixed criteria for the age of a kidney transplant recipient, it is usually recommended for persons from 5 to 65 years of age.
There are three sources of kidneys for transplantation:
An identical twin is an ideal kidney donor with the best chances of survival after transplantation.
A healthy person with two kidneys can donate one kidney as long as the blood group, tissue type and tissue crossmatching are compatible with the recipient. Generally, donors should be between the ages of 18 and 65 years.
Blood group compatibility is important in KT. The recipient and donor must have either the same blood group or compatible groups. Just like in blood transfusions, a donor with blood group O is considered a “universal” donor. (see table below)
Recipient’s blood group | Donor’s blood group |
---|---|
O | O |
A | A or O |
B | B or O |
AB | AB,A, B or O |
A living donor should be thoroughly evaluated medically and psychologically to ensure that it is safe for him or her to donate a kidney. A person cannot donate kidney if he or she has diabetes mellitus, cancer, HIV, kidney disease, high blood pressure or any major medical or psychiatric illness.
A potential donor is evaluated thoroughly to ensure that it is safe for him or her to donate a kidney. With a single kidney, most donors live a normal healthy life. After kidney donation sexual life is not affected. A woman can have children and a male donor can father a child. Potential risks of kidney donation surgery are the same as those with any other major surgery. Risk of contracting kidney disease in kidney donors is not any higher just because they have only one kidney.
Living donor kidney transplantation has several advantages over deceased donor kidney transplantation or dialysis. Many patients with end-stage kidney disease have healthy and willing potential kidney donors but the hurdle is blood group or cross match incompatibility.
Paired kidney donation (also known as “live donor kidney exchange”, “living donor swap” or “kidney swap”) is the strategy which allows the exchange of living donor kidneys between two incompatible donor/ recipient pairs to create two compatible pairs.
This can be done if the second donor is suitable for the first recipient, and the first donor is suitable for the second recipient (as shown above). By exchanging the donated kidneys between the two incompatible pairs, two compatible transplants can be performed.
Kidney transplantation usually takes place after a variable period of dialysis therapy. Kidney transplantation may be done before the initiation of maintenance dialysis when the renal function is less than 20 ml/min. This is called a pre-emptive KT.
Pre-emptive KT is considered the best option for kidney replacement therapy in medically suitable patients with end stage kidney disease (ESKD) because it not only avoids the risks, cost, and inconvenience of dialysis, but also is associated with better graft survival than transplantation performed after initiating dialysis. Because of its benefits, one is strongly advised to consider a pre-emptive transplantation in ESKD, if a suitable donor is available.
Before surgery, medical, psychological and social evaluation is done to ensure fitness and safety of both the recipient and the donor (in living-kidney donor transplant). Testing also ensures proper blood group and HLA matching and tissue cross-matching.
Kidney transplantation is a teamwork of the nephrologists, transplant surgeon, pathologist, anaesthesiologist and supporting medical (cardiologist, endocrinologist, etc.) and nursing staff as well as transplant coordinators.
After a thorough explanation of the procedure a careful reading of the consent form, consent of both the recipient and the donor (in living kidney donation) is obtained.
In living-kidney donor transplant surgery, both the recipient and the donor are operated on simultaneously.
This major surgery lasts from three to five hours and is performed under general anaesthesia.
In living-kidney donor transplant surgery, usually the left kidney is removed from the donor either by open surgery or by laparoscopy. After removal, the kidney is washed with a special cold solution and subsequently placed into the right lower (pelvic) part of the abdomen of the recipient.
In most cases, the old diseased kidneys of the recipient are not removed.
When the source of kidney is a living donor, the transplanted kidney usually begins functioning immediately. However, when the source of the kidney is a deceased (cadaver) kidney donor, the transplanted kidney may take a few days or weeks to begin functioning. The recipient with delayed functioning transplanted kidney needs dialysis until kidney function becomes adequate.
After the transplant, the nephrologist supervises the monitoring and medications of the recipient. Living donors should also be screened and monitored regularly for any health issues that may develop.
The common possible complications after transplantation include rejection, infection, medication side effects and post-operative complications.
Major considerations in post-transplant care are:Post-transplant medications and kidney rejection.
Precautions to keep the transplanted kidney healthy and to prevent infections.
In most cases of routine surgery, post-surgical medications and care are needed for about 7-10 days. However, after kidney transplantation, lifelong regular medications and meticulous care are mandatory.
The immune system of the body is designed to recognize and destroy foreign proteins and antigens like harmful bacteria and viruses. When the recipient’s immune system recognizes that the transplanted kidney is not ‘its own,’ it attacks the transplanted kidney and tries to destroy it.
This attack by the body’s natural defence on a transplanted kidney is known as rejection. Rejection occurs when the transplanted kidney is not accepted by the body of the transplant recipient.
Rejection of the kidney can occur at any time after the transplant, most commonly in the first six months. The severity of rejection varies from patient to patient. Most rejections are mild and easily treated by proper immunosuppressant therapy. In a few patients however, rejection may be severe not responding to therapy and eventually destroying the kidney.
Because of the immune system of the body, there is always a risk of rejection of the transplanted kidney.If the immune system of the body is suppressed the risk of rejection is decreased. However, the patient becomes prone to life-threatening infections.Special drugs are given to patients after kidney transplantation to selectively alter the immune system and prevent rejection, but minimally impair the ability of the patient to fight infections.
Such special drugs are known as immunosuppressant drugs. At present, the most widely used immunosuppressant drugs are tacrolimus/cyclosporine, mycophenolate mofetil (MMF), Sirolimus/ everolimus and prednisolone.
Immunosuppressant medications have to be given throughout life, for as long as the kidney graft is functioning. In the immediate post-transplant period, several drugs are given but their numbers and dosages are gradually reduced over time.
Yes. After kidney transplant, in addition to immunosuppressant drugs, antihypertensive drugs, calcium, and medications to treat or prevent infection and anti-peptic ulcer medications may be prescribed.
Common side effects of immunosuppressant drugs are summarized in the following table.
When a transplanted kidney fails, the patient may either undergo a second transplant or undergo dialysis.
Successful kidney transplant provides a new, normal, healthy and independent life. However, the recipient must live a disciplined lifestyle and follow precautions to protect the transplanted kidney and prevent infections. The patient has to be compliant and take prescribed medications regularly and without fail.
A kidney transplant is the most effective and best treatment option for patients with chronic kidney disease - end stage kidney failure. There is a large number of patients who need or wish to obtain a kidney transplant. There are three important reasons for the limited feasibility of the procedure.
Only a few patients are luckyto obtain either living (related or non-related) or deceased (cadaveric) kidney donors. Major problems are the limited availability of living donors and the long waiting list for deceased donors.
The cost of transplant surgery and the post-transplant lifelong medications is very high. This is a major hurdle for a large number of patients in developing countries.
In many developing countries, facilities for kidney transplantation are not readily or easily available.
Deceased (cadaver) transplantation involves transplanting a healthy kidney from a patient who is “brain dead” into a patient with CKD. The deceased kidney comes from a person who has been declared “brain dead” with the desire to donate organs having been expressed either by the family or by the patient previously, at the event of his/her death.
Due to the shortage of living donors, many CKD patients, though keen to have a transplant, have to remain on maintenance dialysis. The only hope for such patients is a kidney from deceased or cadaver donors. The most noble human service is being able to save the lives of others after death by donating organs. A deceased kidney transplant also helps eliminate illegal organ trade and is the most ethical form of kidney donation.
“Brain death” is the complete and irreversible cessation (stopping) of all brain functions that leads to death. The diagnosis of “brain death” is made by doctors in hospitalized unconscious patients on ventilator support.
An unconscious patient may or may not need the support of a ventilator and is likely to recover after proper treatment. In a patient with “Brain Death,” the brain damage is severe and irreversible and is not expected to recover despite any medical or surgical treatment. In a patient with “Brain Death”, as soon as the ventilator is switched off, respiration stops and the heart stops beating. It is important to remember that the patient is already legally dead and removing the ventilator is not the cause of death. Patients with “Brain Death” cannot remain on ventilator support indefinitely, as their heart will stop relatively soon.
No. Death occurs after the heart and respiration stop irreversibly and permanently. Like corneal donation, after death, kidney donation is not possible. When the heart stops, the blood supply to the kidney also stops, leading to severe and irreversible damage to the kidney, preventing its use for kidney transplantation.
Common causes of brain death are head injuries (i.e. falls or vehicular accidents), intracranial brain haemorrhage, brain infarct and brain tumour.
When a deeply comatose patient kept on ventilator and other life supporting devices for an adequate period does not show any improvement on clinical and neurological examination, the possibility of “Brain Death” is considered. Diagnosis of brain death is made by a team of doctors who are not involved in kidney transplantation This team includes the attending physician, neurologist or neurosurgeon, who, after independent examinations of the patient, declare “brain death.” By detailed clinical examination, various laboratory tests, special EEG test for brain and other investigations, all possibilities of recovery from brain damage are explored. When no chance of any recovery is confirmed, “brain death” is declared.
Under the following conditions a kidney cannot be accepted from a donor with brain death:
Cadaver donors can donate both kidneys and save lives of two patients. Besides kidney, other organs which can be donated are eye, heart, liver, skin, pancreas etc.
For deceased (cadaveric) kidney transplantation proper team work is necessary. The team includes:
These are essential aspects of deceased kidney transplantation.A proper diagnosis of brain death is mandatory.The donor kidneys should be confirmed to be reasonably healthy and the donor should have no systemic disease that would contraindicate donation.Consent to donation should be given by a relative or person who is legally allowed to do so.Donor is kept on ventilator and other life-supporting devices to maintain respiration, heart beat and blood pressure until both kidneys are removed from the body.
After removal, the kidney is processed properly with a special cold fluid and is preserved in ice. One deceased donor can donate both kidneys, so two recipients can be given the gift of life.
Appropriate recipients are selected from a waiting list of patients following a protocol based on blood group, HLA matching and tissue cross matching compatibility.
Better outcomes are expected the earlier the harvested kidneys are transplanted.
They should ideally be transplanted within 24 hours of harvest.
Beyond a certain length of time, they may not be viable for transplantation anymore.
The surgical procedure on the recipient is the same for both living or deceased kidney donation.
During the period of time between harvest and transplantation, the donor kidney sustains some damage due to lack of oxygen, lack of blood supply and cold exposure from storage in ice. Because of such injury, the kidney may not function immediately after transplantation and on occasion, short term dialysis support may be necessary while waiting for the donor kidney to recover and regain function.
None. Giving another person a new lease on life is an invaluable gift. Being a donation, the donor or the donor’s family should not expect to receive any payment in exchange for the donated kidney, neither does the recipient need to pay anyone. The joy and satisfaction for this humanitarian gesture should be enough compensation for the donor or the family.