Acute Kidney Injury in Deceased Organ Donors and Kidney Transplant Outcomes: A National Cohort Study Using a Novel Data Source.

OBJECTIVE: The aim of this study was to determine graft function and survival for kidney transplants from deceased donors with acute kidney injury (AKI) that persists at the time of organ procurement. BACKGROUND: Kidneys from donors with AKI are often discarded and may provide an opportunity to selectively expand the donor pool. METHODS: Using Organ Procurement and Transplantation Network and DonorNet data, we studied adult kidney-only recipients between May 1, 2007 and December 31, 2016. DonorNet was used to characterize longitudinal creatinine trends and urine output. Donor AKI was defined using KDIGO guidelines and terminal creatinine ≥1.5 mg/dL. We compared outcomes between AKI kidneys versus "ideal comparator" kidneys from donors with no or resolved AKI stage 1 plus terminal creatinine <1.5mg/dL. We fit proportional hazards models and hierarchical linear regression models for the primary outcomes of all-cause graft failure (ACGF) and 12-month estimated glomerular filtration rate (eGFR), respectively. RESULTS: We identified 7660 donors with persistent AKI (33.2% with AKI stage 3) from whom ≥1 kidney was transplanted. Observed rates of ACGF within 3 years were similar between recipient groups (15.5% in AKI vs 15.1% ideal comparator allografts, P = 0.2). After risk adjustment, ACGF was slightly higher among recipients of AKI kidneys (adjusted hazard ratio 1.05, 95% confidence interval: 1.01-1.09). The mean 12-month eGFR for AKI kidney recipients was lower, but differences were not clinically important (56.6 vs 57.5 mL/min/1.73m 2 for ideal comparator kidneys; P < 0.001). There were 2888 kidneys discarded from donors with AKI, age ≤65 years, without hypertension or diabetes, and terminal creatinine ≤4 mg/dL. CONCLUSION: Kidney allografts from donors with persistent AKI are often discarded, yet those that were transplanted did not have clinically meaningful differences in graft survival and function.

Pregnancy Outcomes After Living Liver Donation: A Multi-Institutional Study.

Nearly half of living liver donors in North America are women of child-bearing age. Fetal and maternal outcomes after donation are unknown. We conducted a retrospective cohort study of female living liver donors (aged 18-50 years at donation) from 6 transplant centers. Participants were surveyed about their pregnancies and fertility. Outcomes were compared between predonation and postdonation pregnancies. Generalized estimating equations were clustered on donor and adjusted for age at pregnancy, parity, and pregnancy year. Among the 276 donors surveyed, 151 donors responded (54.7% response rate) and reported 313 pregnancies; 168/199 (68.8%) of the predonation pregnancies and 82/114 (71.9%) of the postdonation pregnancies resulted in live births, whereas 16.6% and 24.6% resulted in miscarriage, respectively. Women with postdonation pregnancies were older (32.0 versus 26.7 years; P < 0.001) and more frequently reported abnormal liver enzymes during pregnancy (3.5% versus 0.0%; P = 0.02) and delivery via cesarean delivery (35.4% versus 19.7%; P = 0.01). On adjusted analysis, there was no difference in cesarean delivery (odds ratio [OR], 2.44; 95% confidence interval [95% CI], 0.98-6.08), miscarriage (OR, 1.59; 95% CI, 0.78-3.24), combined endpoints of pregnancy-induced hypertension and preeclampsia (OR, 1.27; 95% CI, 0.36-4.49), or intrauterine growth restriction and preterm birth (OR, 0.91; 95% CI, 0.19-4.3). Of the 49 women who attempted pregnancy after donation, 11 (22.5%) self-reported infertility; however, 8/11 (72.7%) eventually had live births. Aside from increased reporting of abnormal liver enzymes and cesarean deliveries, there was no significant difference in pregnancy outcomes before and after living liver donation. One-fifth of women who attempt pregnancy after liver donation reported infertility, and although the majority went on to successful live births, further exploration is needed to understand the contributing factors. Future research should continue to monitor this patient-centered outcome across a large cohort of donors.

Wide Variation in the Percentage of Donation After Circulatory Death Donors Across Donor Service Areas: A Potential Target for Improvement.

BACKGROUND: Substantial differences exist in the clinical characteristics of donors across the 58 donor service areas (DSAs). Organ procurement organization (OPO) performance metrics incorporate organs donated after circulatory determination of death (DCDD) donors but do not measure potential DCDD donors. METHODS: Using 2011-2016 United Network for Organ Sharing data, we examined the variability in DCDD donors/all deceased donors (%DCDD) across DSAs. We supplemented United Network for Organ Sharing data with CDC death records and OPO statistics to characterize underlying process and system factors that may correlate with donors and utilization. RESULTS: Among 52 184 deceased donors, the %DCDD varied widely across DSAs, with a median of 15.1% (interquartile range [9.3%, 20.9%]; range 0.0%-32.0%). The %DCDD had a modest positive correlation with 4 DSA factors: median match model for end-stage liver disease, proportion of white deaths out of total deaths, kidney center competition, and %DCDD livers by a local transplant center (all Spearman coefficients 0.289-0.464), and negative correlation with 1 factor: mean kidney waiting time (Spearman coefficient -0.388). Adjusting for correlated variables in linear regression explained 46.3% of the variability in %DCDD. CONCLUSIONS: Donor pool demographics, waitlist metrics, center competition, and DCDD utilization explain only a portion of the variability of DCDD donors. This requires further studies and policy changes to encourage consideration of all possible organ donors.

Association of Kidney Transplant Center Volume With 3-Year Clinical Outcomes.

RATIONALE & OBJECTIVE: A robust relationship between procedure volume and clinical outcomes has been demonstrated across many surgical fields. This study assessed whether a center volume-outcome relationship exists for contemporary kidney transplantation, specifically for diabetic recipients, older recipients (aged ≥65 years), and recipients of high kidney donor profile index (KDPI ≥ 85) kidneys. STUDY DESIGN: Retrospective cohort study. SETTING & PARTICIPANTS: Adult kidney-only transplant recipients who underwent transplantation between 2009 and 2013 (N = 79,581). EXPOSURES: The primary exposure variable was center volume, categorized into quartiles based on the total kidney transplantation volume. Quartile 1 (Q1) centers performed a mean of fewer than 66 kidney transplantations per year, whereas Q4 centers performed a mean of more than 196 kidney transplantations per year. OUTCOMES: All-cause graft failure and mortality within 3 years of transplantation. ANALYTICAL APPROACH: Multivariable Cox frailty models were used to adjust for donor characteristics, recipient characteristics, and cold ischemia time. RESULTS: Minor differences in rates of 3-year deceased donor all-cause graft failure across quartiles of center volume were observed (14.9% for Q1 vs 16.7% for Q4), including in subgroups (diabetic recipients, 18.4% for Q1 vs 19.7% for Q4; older recipients, 19.4% for Q1 vs 22.5% for Q4; recipients of high KDPI kidneys, 26.5% for Q1 vs 26.5% for Q4). Results were similar for 3-year mortality. After adjustment for donor, recipient, and graft characteristics using Cox regression, center volume was not significantly associated with all-cause graft failure or mortality within 3 years, except that diabetic recipients at Q3 centers had slightly lower mortality (compared with Q1 centers, adjusted HR of 0.85 [95% CI, 0.73-0.99]). LIMITATIONS: Potential unmeasured confounding from patient comorbid conditions and organ selection. CONCLUSIONS: These findings provide little evidence that care in higher volume centers is associated with better adjusted outcomes for kidney transplant recipients, even in populations anticipated to be at increased risk for graft failure or death.