"This shows that a small kidney stone should not preclude people from being donors,” says George Chow, M.D., Mayo Clinic urologist and senior investigator of the study. "It's not likely for the stones to grow if transplanted.”

His colleague investigator, Khai-Linh Van Ho, M.D, Mayo Clinic urology fellow, agrees. "We found the stones did not affect the function of the kidney. As far as we know with 26 months of follow-up, we've had no loss of kidneys from obstruction. The grafted kidney survival rate was 97 percent - the same as the national survival rate for living kidney donation. That's relatively safe.”

In the Mayo study, a retrospective chart and radiograph review of 710 donor kidneys, 44 had stones. Of these, 86 percent had 1- to 2-millimeter stones and 14 percent had 3- to 6-millimeter stones. CT scans performed an average of 10.5 months after transplant surgery in 14 patients showed no stones in six patients, stable stone size in four patients and increase in stone size averaging 2.9 millimeters in four patients. No loss of the transplanted kidneys occurred due to stone obstruction in the patients studied.

Helping patients is the reason for investigating transplant of kidneys that previously would have been considered questionable, explain Dr. Ho and Dr. Chow. "Our motivation is to save lives and improve quality of life,” Dr. Ho says. "The idea is that patients would do better off dialysis and mortality rates would decrease. There would also be fewer burdens on the economy if more patients were transplanted and off dialysis.”

Transplantation of a kidney which has stones occurs with full consent of the donor, recipient and transplant surgeon, and only after all parties undergo in-depth discussion about the kidney and any potential risks, says Dr. Ho.

MEDICA.de; Source: Mayo Clinic