Background Kidney transplantation is the optimal treatment for the maj
ority of patients with end-stage renal disease. However, the shortage
of kidneys for transplantation is a global problem, and any attempt to
improve the donor situation would be of benefit to the growing number
of patients on transplant waiting lists. Patients and methods. Since
1984, we have transplanted 141 kidneys from genetically unrelated livi
ng donors. Donors were most often spouses and were accepted regardless
of HLA match grade. Preemptive transplantation was performed in 39% o
f the patients. Standard triple-drug immunosuppression with prednisolo
ne, cyclosporine, and azathioprine was used. The patients were followe
d from 6 months to 13 years. Results. The incidence of acute rejection
during the first 3 months after transplantation was higher in recipie
nts of grafts from unrelated donors than in recipients of grafts from
related living donors or cadaveric donors, However, unrelated living d
onor grafts survived significantly better than did cadaveric grafts (P
<0.02) and had a survival rate similar to that of living-related donor
grafts mismatched for one or both HLA haplotypes, The perioperative c
omplication rate for the donor was low. Conclusion. We consider unrela
ted living donors an excellent source for alleviating the shortage of
donor kidneys.