Kidney transplantation is the preferred therapy after kidney failure, but kidneys transplanted from deceased donors often do not last for the rest of a recipient's life.

Because of the scarcity of donor organs and the immunological sensitisation of transplant recipients, it's unclear whether patients whose transplanted kidneys are no longer functioning should receive second transplants, or whether they should be treated with dialysis. A study published in the journal CJASN compares these options.

For the study, a team led by Rainer Oberbauer, MD (the Medical University of Vienna, in Austria) analysed data pertaining to 2,346 adults with a failed first kidney transplant who were waitlisted for a second kidney transplant in Austria during 1980-2019.

At a 10-year follow-up point, patients who received a second kidney transplant had a longer average survival time compared with those who underwent dialysis while remaining on the transplant waitlist. Specifically, patients who underwent retransplantation lived for an average of 5.8 months longer.

The difference in survival time with retransplantation was lower in patients who had a long wait time after their first transplant failed, however. At the 10-year follow-up point, patients who underwent retransplantation lived for an average of 8.0 and 0.1 months of additional life for patients with a waiting time of less than 1 year and 8 years, respectively.

"Our data showed that a second transplantation is advantageous regarding gained life years; however, the difference to non-transplanted patients decreases with time on the waiting list," said Dr Oberbauer. "Nevertheless, patients might have a higher quality of life when transplanted and therefore should get a second transplant if a suitable donor organ is available." Dr Oberbauer stressed that patients with a failed first kidney transplant should be waitlisted immediately if they are fit to undergo second transplantation.

An accompanying editorial notes that "if these results are reproduced in imitated trials from other countries, it would signify the importance of decreasing time on the waiting list for second kidney transplant candidates by measures such as expedited work-up and enlistment of patients with failing first kidney transplants before they require dialysis."