Effect of Cold Ischemia Time on Kidney Graft Function and Survival: Differences Between Paired Kidney Transplants From the Same Donor.

INTRODUCTION: Kidney transplantation procedures commonly result in a cold ischemia time (CIT) gap when both kidney grafts are implanted in the same center. Owing to logistics, the procedure is usually consecutive, first accomplishing one surgery and then the other. CIT constitutes an independent risk factor for the development of delayed graft function (DGF) in kidney transplants. The effect that CIT exerts on graft and patient survival is still unclear. This study evaluates the relation of CIT and transplant outcomes by comparing paired kidney transplants in terms of survival and graft function. METHODS: We accomplished a retrospective analysis of 402 kidney transplants performed in our center between 2000 and 2017. We selected all transplants where both organs from the same donor were implanted at our hospital, establishing 2 study groups (group 1: first graft implanted and group 2: second graft implanted) to compare by paired data statistical methods. RESULTS: We found an increase in the incidence of DGF in group 2 (42% vs 28.8%; P < .05). Group 2 had significantly worse graft function on day 5 posttransplant (4.7 ± 2.88 vs 3.86 ± 2.8 mg/dL of serum creatinine; P < .05). No significant differences in graft function were found on days 30 and 90 posttransplant. We didn't find any difference in graft survival between both groups. Length of hospitalization stay (17.6 days [± 13] vs 21.6 days [± 17]) and hemodialysis sessions (mean of 2.8 [± 2] vs 3.6 [± 2.2]) were higher in group 2. CONCLUSION: CIT acts as an independent risk factor for the development of DGF in kidney transplantation. CIT had no isolated effect on graft survival.

Usefulness of Delayed Introduction of Tacrolimus in Kidney Transplants Using Type-III Donors After Circulatory Death.

INTRODUCTION: Our study compares 2 immunosuppressive strategies to reduce tacrolimus nephrotoxicity and its risk of acute tubular necrosis: delayed introduction of tacrolimus plus thymoglobulin vs initial tacrolimus plus basiliximab on the results of kidney transplant (KT) using type-III donation after circulatory death (III-DCD). MATERIAL AND METHODS: We analyzed all the transplants performed using type-III DCD in our hospital (42 cases). They were distributed in a first stage with delayed tacrolimus (3°-4° day) + thymoglobulin and a second one with initial tacrolimus + basiliximab, with a follow-up of 6 months. The rate of delayed graft function, the evolution of renal function, and the incidence of rejection were compared. RESULTS: 28 patients received thymoglobulin with delayed tacrolimus, and 13 patients received basiliximab and tacrolimus from day 0 (1 excluded). There were no significant differences in delayed graft function (27% group 1 and 23% group 2) or in rejection (10.7% and 15.4%), respectively. Serum creatinine at day 3, 7, 14, 30, and 180 showed no statistically significant differences. The levels of tacrolimus measured at 10, 30, 90, and 180 days after transplantation were similar, except for the first month: 10.10 ± 2.3 in group 1 and 12 ± 1.7 ng/mL in group 2 (P = .007). CONCLUSIONS: Delayed introduction of tacrolimus does not seem to suppose a benefit in KT using type-III DCD; therefore, the use of thymoglobulin, with its higher profile of adverse effects, seems unjustified in patients with normal immunological risk.

Relationship Between Albuminuria During the First Year and Antibody-Mediated Rejection in Protocol Biopsies in Kidney Transplant Recipients.

BACKGROUND: Antibody-mediated rejection is the main cause of deterioration of kidney transplants and frequently is detected only by means of protocol biopsies. The aim of this study was to relate the presence of albuminuria throughout the 1st year to the histologic findings detected by 1-year protocol biopsies in kidney graft recipients. METHODS: Retrospective observational study of 86 protocol biopsies 1 year after transplantation. Albuminuria was measured at 3, 6, 9, and 12 months in urine samples and expressed as albumin/creatinine (mg/g). RESULTS: Analysis of biopsies, reflected according to the Banff criteria, the following categories: fibrosis and tubular atrophy, 35 (40.7%); cellular rejection, 13 (15.1%); antibody-mediated rejection, 8 (9.3%); chronic glomerulopathy, 10 (11.6%); normal, 14 (16.3%); recurrence, 1 (1.2%); and other, 5 (5.8%). The proportions of patients with albuminuria for Banff scale scores (0 vs ≥1, respectively) at 6 and 12 months, respectively, after transplantation, were: for marker glomerulitis, 45.5% versus 59.3% (P = .021) and 36.4% versus 70.4% (P < .001); for marker glomerulopathy, 49.1% versus 50.0% (P = .051) and 42.1% versus 58.3% (P = .019); for marker peritubular capillaritis, 45.8% versus 60.9% (P = .047) and 39.0% versus 69.6% (P = .276); and for marker C4d, 49.2% versus 56.3% (P = .894) and 46.2% versus 56.3% (P = .774). CONCLUSIONS: The presence of albuminuria after renal transplantation is common, especially in patients with proteinuria. Persistent albuminuria after transplantation, even at low levels, can be indicative of subclinical antibody-mediated rejection. Additional broader studies to relate the albuminuria to histologic changes observed in protocol biopsies are required.