RESUMO
BACKGROUND: Information regarding the clinical characteristics and outcomes of kidney transplant recipients (KTRs) with > 25 years of graft survival is limited. METHODS: In this single-center observational study, we characterized KTRs transplanted between 1973 and 1992 with active follow-up as of July 31, 2017. RESULTS: We identified 112 patients with > 25 years of allograft function. The mean posttransplantation follow-up was 29.8 ± 4.0 years. Glomerulonephritis was the most common cause of end-stage renal disease (ESRD) (52%). The majority received live donor transplants (66%), including 25 patients (22%) with human leukocyte antigen-matched kidneys. The incidence of biopsy-confirmed acute rejection was 21%, ranging from 0 to 26 years post transplantation. Donor-specific antibodies (DSA) were checked in 80% of patients at a mean of 28.4 ± 0.11 years post transplantation. Of these, only 15% were positive. The incidence of malignancy was 44%, with nonmelanoma skin cancers being most common. The incidence of infectious complications was 77%, mostly represented by urinary tract infections. At the time of last follow-up, 63% were on a calcineurin inhibitor (CNI)-free regimen, mean serum creatinine was 1.4 ± 0.6 mg/dL, and the prevalence of hypertension and dyslipidemia was 89 and 88%, respectively. CONCLUSION: The majority of patients with a long-term functioning graft had glomerulonephritis as cause of ESRD, had received a live donor kidney, were on a CNI-free regimen, and had a low incidence of DSA and opportunistic infections. These characteristics define a unique group of patients requiring specific posttransplantation monitoring and management.
RESUMO
BACKGROUND: Tolerance to noninherited maternal antigens has provided clinical advantage when kidney transplants are exchanged between siblings but not when mother herself is the donor. This paradox prompted us to revisit the "two-way" hypothesis of transplant tolerance--that the immune status of both the organ recipient and the organ donor critically influences allograft outcome. METHODS: We obtained peripheral blood monocyte cells from 29 living donor-recipient pairs before transplant and used the trans-vivo-delayed type hypersensitivity assay to measure immune regulation in both the recipient antidonor and donor antirecipient directions. RESULTS: We found preexisting bidirectional regulation in all human leukocyte antigen (HLA)-identical sibling pairs tested (7/7), and one half (9/18) of the HLA haploidentical pairs. No significant regulation was found in four control living unrelated and two HLA haploidentical living-related donor recipient pairs, whereas unidirectional regulation was found in the remaining seven haploidentical pairs. Of the nine HLA haploidentical transplants with unidirectional or no pretransplant regulation, seven had an acute rejection episode and four of these experienced graft loss. In contrast, of the nine HLA haploidentical transplants with bidirectional regulation, only one had rejection. Renal function for the latter group was similar to HLA-identical kidney recipients at 3 years posttransplant. Significantly (P<0.05) lower mean serum creatinine values in bidirectional regulators were noted as early as 4 months and this difference became more pronounced at 12 (P<0.005) and 36 months (P<0.0001). CONCLUSIONS: Contrary to the belief that only the recipient's immune status matters, the data indicate that pretransplant immune status of both donor and recipient influence posttransplant outcome.
