Kidney transplants come a long way

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The first kidney transplant in Manitoba was done in November 1969. Since then, over 1000 transplants have been performed. In the early days of transplantation, only 50-60% of kidneys from cadaveric donors survived the first year after transplantation. This high failure rate was due to acute rejection. In the early 1980’s, Cyclosporine was introduced as an anti-rejection drug and with this one-year survival rates improved to over 80%. With the addition of other drugs such as mycophenolate mofetil (CellCept), tacrolimus (Prograf¨), and monoclonal antibodies such as OKT3 (Orthoclone) and Basiliximab (Simulect), further improvements in kidney survival have occurred. Major improvements in the transplant laboratory in the identification of recipients who have immunity against the donor have also made a major contribution to the improved survival of grafts. The new technology identifies low levels of anti-donor antibodies, which could not be detected previously. In addition, the specific nature of the antibodies in potential recipients can be identified allowing for better selection of donors. With these improvements, kidney survival from cadaveric donors is now more than 90% at one year and the average kidney will last over 10 years.

The improvements in recipient donor matching and immunosuppression have resulted in less than 30% of patients having an acute rejection episode in the first year post transplant. However, there is still a steady failure rate of transplants in the order of 2-3% per year after the first year. The most common cause of long-term graft loss is now death of the patient, most commonly due to cardiovascular events. The second most common cause of long-term kidney loss is chronic kidney damage which may be the result of chronic rejection or other factors such as hypertension or drug toxicity.

Over the last 7-8 years there has been a dramatic decrease in the number of cadaveric donors. This has resulted in increased waiting times for transplant for those who are dependant upon organs donated after death and this wait now averages three years. This shortage has resulted in more patients depending on living donors as the source of their kidney. In the early years of transplantation only genetically related and matched donors were allowed to donate. Over the last decade, it has been shown that with modern recipient-donor matching and immunosuppression that unrelated living donors such as a spouse or friend can be the donor. Therefore, in the last few years, almost half of the kidneys transplanted in Manitoba have been from living donors. The results of transplantation in these patients is better than with a cadaveric kidney with expected average graft survivals in the 15-20 year range.

The major challenges faced by the Program at this time are improving the rate of cadaveric organ donation and the avoidance of the long-term side effects and toxicities of anti-rejection therapy.