Introduction
A renal transplant can perform all the functions of a normal kidney by removing waste products and water as well as producing the hormones produced by the normal kidney, and is a solution for patients with severe or irreversible kidney failure. Dialysis is another option of therapy for such patients. However, not all patients are suitable for both forms of therapy. The choice of one treatment over the other for any individual patient is based on many factors including medical and social factors, as well as the availability of these options for the individual patient. Thus some patients with heart disease are not suitable for kidney transplantation, and will need to remain on dialysis. Some patients with severe heart disease or other debilitating illnesses may not even tolerate dialysis. Every patient will need to be evaluated individually to decide whether he or she is suitable for either form of treatment.
Renal transplantation usually remains the most ideal option of renal replacement therapy. With a functioning renal transplant (also called allograft), the patient is freed from the need of having to do dialysis, can have a normal diet, and can in almost all respects have a normal unimpeded lifestyle.
Different Forms of Renal Transplantation
There are several forms of renal transplantation:
Cadaveric renal transplantation:
Some patients on dialysis have no family members suitable to donate a kidney to them. These patients need to wait for kidney that is obtained from a suitable donor who has died suddenly but had otherwise been in a good state of health. Such a transplant is called a cadaveric renal transplant. Patients on dialysis if suitable will be placed on the transplantation list and await the opportunity for a transplantation while receiving regular dialysis. The waiting time depends on the availability of willing donors, and in Singapore, recipients of a cadaveric renal transplant commonly wait about 4 to 6 years before receiving a transplant. Some have waited as long as ten years. The success rate however is about 10% lower than that of a live donor transplant, but nevertheless, usually still means a better quality of life than being on dialysis.
Living related renal transplantation:
This refers to a renal transplant obtained from a living and healthy relative of the recipient. Healthy family members such as the sibling, parent, or first and second-degree relatives (i.e. cousin) of the patient could offer his or her kidney. The donor undergoes extensive testing to ensure that he or she is suitable to donate a kidney. The kidneys of such harvests work very well, and the recipient needs to wait on dialysis only as long as the evaluation of the donor is being done. This evaluation takes about 3 months, on average. Once the donor is considered so be suitable the donor will undergo an operation to remove the kidney for transplantation to his relative. The donor recovers completely by 6 weeks after the operation and can return to a normal life thereafter. Transplants performed from related donors have very high success rates, in excess of 97% at our centre.
A donor evaluation can be performed in as short a time as one month; in fact one of the advantages of a living related kidney transplant is that the patient may not even need to be on dialysis if there is a suitable donor. More often however, donor evaluation takes 3 months on the average, and the potential recipient needs to wait on dialysis during the period. As the success rate for a living related kidney transplant is the best, this is the first choice treatment of patients with kidney failure who are suitable for a kidney transplant.
Living unrelated renal transplantation:
This refers to renal transplant from a living healthy unrelated person that is emotionally related to the patient. Only the spouse in a stable marriage could qualify as such a donor. The medical tests that the donor needs to go through are essentially the same as that of a donor who is related to the recipient. Again the waiting time for a kidney for the recipient is only as long as the evaluation of the donor, which is also about 3 months.
Options for renal replacement will vary between patients because of medical, social and financial reasons. An option that seems best for a particular patient may not necessarily also be as good for another patient. It is wise for patients to discuss with their physicians and renal staff of the options that they should best choose before making a final decision.
Possible Risks
As the kidney that is transplanted is recognised as foreign by the body, the body's immune system, which can reject the kidney, must be kept in check by powerful drugs called immunosuppressants.
Transplant patients must continue these drugs for life, as these drugs suppress the rejection process and successfully protect the kidney. This however comes with a price as these drugs also lower the patient's resistance to infection. Patients are at an increased risk of getting infections.