Age-modified risk factors for mortality of non-elderly adult kidney transplant recipients: a retrospective database analysis.

PURPOSE: We aimed to investigate the role of the recipient's age strata in modifying the associations between risk factors and mortality in non-elderly adult kidney transplant (KT) recipients (KTR). METHODS: We stratified 108,695 adult KTRs between 2000 and 2016 with conditional 1-year survival after KT into cohorts based on age at transplant: 18-49 years and 50-64 years. We excluded KTRs aged < 18 years or > / = 65 years. KTRs were observed for 5 years during the 2nd through 6th years post-KT for the outcome, all-cause mortality. RESULTS: Increasing recipient age strata (18-49-year-old and 50-64-year-old) correlated with decreasing 6-year post-KT survival rates conditional on 1-year survival (79% and 57%, respectively, p < 0.0001). Middle adult age stratum was associated with a higher risk of all-cause mortality than young adult age stratum in KTRs of Hispanic/Latino and other races [HR = 1.23, 95% CI = 1.04-1.45 and HR = 1.51, 95% CI = 1.16-1.97, respectively] and with a primary native renal diagnosis of hypertension or glomerulonephritis [HR = 1.32, 95% CI = 1.12-1.55 and HR = 1.29, 95% CI = 1.10-151, respectively]. When compared with the young adult age stratum, the middle adult age stratum had a mitigating effect on the higher risk of mortality associated with sirolimus-mycophenolate or sirolimus-tacrolimus than the standard calcineurin inhibitor-mycophenolate regimen [HR = 0.75, 95% CI = 0.57-0.99 and HR = 0.71, 95% CI = 0.57-0.89, respectively]. CONCLUSION: Among adult non-elderly KTRs, the age strata, 18-49 years, and 50-64 years, have varying modifying effects on the strength and direction of associations between some specific risk factors and all-cause mortality.

Role of standard HLA mismatch in modifying associations between non-pharmacologic risk factors and solid organ malignancy after kidney transplantation.

BACKGROUND: Human leukocyte antigen mismatch(es) (HLA-mm) between donors and recipients has not been extensively studied either as a risk factor for solid organ malignancy (SOM) or as a modifier of associations between nonpharmacologic risk factors and SOM in kidney transplant recipients (KTRs). METHODS: In a secondary analysis from a previous study, 166,256 adult KTRs in 2000-2018 who survived the first 12 months post-transplant free of graft loss or malignancy were classified into 0, 1-3, and 4-6 standard HLA-mm cohorts. Multivariable cause-specific Cox regressions analyzed the risks of SOM and all-cause mortality (ac-mortality) in 5 years following the first KT year. Comparisons of associations between SOM and risk factors in HLA mismatch cohorts were made by estimating the ratios of adjusted hazard ratios. RESULTS: Compared with 0 HLA-mm, 1-3 HLA-mm was not associated, and 4-6 HLA-mm was equivocally associated with increased risk of SOM [hazard ratio, (HR) = 1.05, 95%, confidence interval (CI) = 0.94-1.17 and HR = 1.11, 95% CI = 1.00-1.34, respectively]. Both 1-3 HLA-mm and 4-6 HLA-mm were associated with increased risk of ac-mortality compared with 0 HLA mm [hazard ratio (HR) = 1.12, 95%, Confidence Interval (CI) = 1.08-1.18) and (HR = 1.16, 95% CI = 1.09-1.22), respectively]. KTR's history of pre-transplant cancer, age 50-64, and >/=65 years were associated with increased risks of SOM and ac-mortality in all HLA mismatch cohorts. Pre-transplant dialysis >2 years, diabetes as the primary renal disease, and expanded or standard criteria deceased donor transplantation were risk factors for SOM in the 0 and 1-3 HLA-mm cohorts and of ac-mortality in all HLA-mm cohorts. KTRs male sex or history of previous kidney transplant was a risk factor for SOM in the 1-3 and 4-6 HLA-mm cohorts and of ac-mortality in all HLA-mm cohorts. CONCLUSION: Direct association between SOM and the degree of HLA mismatching is equivocal and limited to the 4-6 HLA-mm stratum; however, the degree of HLA mismatching has significant modifying effects on the associations between specific nonpharmacologic risk factors and SOM in KTRs.

Common predictors of adverse outcomes in adult deceased donor kidney transplant recipients with varying sensitization.

OBJECTIVE: Our objective was to identify consistent predictors of multiple adverse outcomes of adult deceased donor (DD) kidney transplant recipients (KTRs) of varying sensitization status. METHODS: We used the national transplant database in studying 62037 adult DD-KTRs between Dec. 2007 and Jun. 2015 stratified into sensitization cohorts based on calculated panel reactive antibody (CPRA) of <10%, 10%-79%, and ≥80%. We used multivariable logistic regressions for the analysis of risks for delayed graft function (DGF), and of acute rejection (AR) and hospitalization in the first year of transplant, and Cox hazard regression for 5-year overall graft loss (OAGL) and death. RESULTS: The kidney donor risk index (KDRI) highest two quartiles ≥1.45 and 1.15-1.44 were the most consistent predictors for 100% of adverse outcomes (OAGL, death, DGF, AR, and hospitalization) with high significance (P<0.0001) across all sensitization cohorts. The two risk factors that were consistently associated with 80% of adverse outcomes across sensitization cohorts were: (1) pre-transplant dialysis duration >2 years was significantly associated with increased risks of overall graft loss, death, DGF, and hospitalization; and (2) Black KTR race was significantly associated with increased risks of DGF, AR, and hospitalization, and decreased risk of death. Diabetes and KTR age >65 (years) were significant risk factors for overall loss and death across sensitization cohorts. CONCLUSIONS: The two highest KDRI quartiles, pre-transplant dialysis duration >2 years, and African American recipient race are consistent predictors of multiple adverse outcomes in adult DDKTRs across sensitization strata and should be among the factors considered in clinical decision-making and research models in kidney transplantation.

Impact of antibody induction on the outcomes of new onset diabetes after kidney transplantation: a registry analysis.

PURPOSE: We conducted this observational study to examine the impact of antibody inductions administered at kidney transplant (KT) on outcomes of 5 year exposure to post-transplant diabetes (PTDM) in adult deceased-donor kidney transplant recipients (DDKTRs). We also studied the risk of PTDM associated with antibody inductions. METHODS: Using 2000-2016 Organ Procurement Transplantation Network data, we employed multivariable Cox models to determine the adjusted hazard ratios (HR) of death, and overall and death-censored graft loss (OAGL, DCGL; respectively) at the 5 year landmark period in antibody induction cohorts with and without PTDM at the 1 year post-transplant index time point. We used multivariable logistic regression in determining the risk factors for PTDM. All multivariable analyses were adjusted for the potential confounding effects of maintenance immunosuppression, steroid regimens, and other relevant covariates. RESULTS: 48,031 adult DDKTRs were classified into cohorts based on antibody induction at transplant: (anti-thymocyte globulin) ATG (n = 26, 788); (alemtuzumab) ALM (n = 5916); and interleukin-2 receptor antagonist (IL-2RA) (n = 15,327). PTDM was a risk factor for 5 year OAGL and death, not DCGL [(HR = 1.25, CI = 1.16-1.36), (HR = 1.13, CI = 1.06-1.21), and (HR = 1.05, CI = 0.96-1.16); respectively]. Induction regimens were not risk factors for 5 year outcomes in DDKTRs with and without PTDM. Risk factors for PTDM included DDKTR obesity, age > / = 50 years, acute rejection, and ATG induction, among others. CONCLUSIONS: In adult DDKTRs, after controlling the confounding effects of clinically relevant variables including maintenance and steroid regimens, PTDM at 1 year post-transplant is associated with death and OAGL, not DCGL in the following 5 years: induction received at KT did not modify these associations.

Association of HLA mismatch and MTOR inhibitor regimens with malignancy and mortality after kidney transplantation.

Background The association of mammalian target of rapamycin inhibitors (MTORI) with malignancies and mortality in kidney transplant recipients (KTR) with different degrees of human leukocyte antigen mismatch (HLA-mm) at transplant has not been previously studied. Methods Our observational cohort study included 166, 256 adult KTRs in 2000-2018. Immunosuppression in the first post-transplant year were MTORIs in 13,056 (7.85%) and non-MTORIs in 153,200 (92.15%). We used Cox multivariable regression models to determine the cause-specific hazard ratio (HRcs) of non-melanoma skin cancer (NMSC),solid organ malignancies (SOM)] and all-cause death (deathac); and the HR of the composite outcomes of NMSC or deathac and SOM or deathac associated with MTORI versus non-MTORI regimens in the overall study sample and the 0, 1-3, and 4-6 HLA-A, B and DR mm subgroups. Results NMSC risk was lower with MTORI than non-MTORI in all HLA-mm subgroups [(0 mm, HRcs = 0.67; 95% CI = 0.46-0.97, 1-3 mm, HRcs = 0.73; 95% CI = 0.61-0.87, 4-6 mm, HRcs = 0.69; 95% CI = 0.62-0.76)]. SOM risks were similar between regimens in the 0 HLA mm subgroup (HRcs = 1.10 (95% CI = 0.78-1.57) and lower with MTORI than non-MTORI in the 1-3, and 4-6 HLA-mm subgroups, [(HR = 0.84; (95% CI = 0.71-0.99), and (HR = 0.86; 95% CI = 0.78-0.94); respectively]. Risks of deathac and composite outcomes (NMSC or deathac and SOM or deathac) were higher with MTORI than non-MTORI in almost all HLA-mm subgroups. Conclusion MTORIs are associated with protection from NMSC and SOM in almost all HLA-mm subgroups ca; however, their association with increased all-cause mortality in adult kidney transplant recipients needs further investigation.

A pilot study of immunosuppression resumption following BK viremia resolution.

BACKGROUND: Immunosuppression reduction for BK viremia is associated with de novo humoral responses, which are a risk factor for rejection and graft loss. In this pilot project, we tested a protocol of immunosuppression resumption to standard dose after viral clearance for optimal protection against humoral immunity in patients undergoing treatment for BK viremia. METHODS: Thirty-six consecutive kidney transplant recipients who developed BK viremia from 7/1/2014 to 11/18/2016 underwent immunosuppression reduction. After 4 weeks of absent viremia, mycophenolate mofetil (MMF) was increased by 500mg/day every 2 weeks up to standard dosage, followed by increase of tacrolimus trough levels to 5-7 ng/mL. If viremia recurred during the increase, immunosuppression was reduced in this same stepwise fashion, with stepwise increase again after 2 months of negative viremia. RESULTS: Mean tacrolimus trough level (ng/mL) was 8.3 ± 2.7 at viremia onset, 5.3 ± 3.6 at resolution, and 5.6 ± 2.0 at study end date. Mean daily dose (mg) of MMF was 1574 ± 355 at onset, 910 ± 230 at resolution, and 1377 ± 451 at study end date. Only one patient developed low level viremia recurrence (peak 2875 copies/mL) during the period of immunosuppression resumption that ultimately resolved. CONCLUSIONS: The results of our pilot project indicate that following BK viremia resolution, resumption of standard immunosuppression can be achieved safely without BK viremia recurrence. Larger trials with long-term follow up are required to determine whether such an approach improves long-term graft survival.

Outcomes of induction antibody therapies in the nonbroadly sensitized adult deceased donor kidney transplant recipients: a retrospective cohort registry analysis.

The outcomes of lymphocyte-depleting antibody induction therapy (LDAIT), [thymoglobulin (ATG) or alemtuzumab (ALM)] versus interleukin-2 receptor antagonist (IL-2RA) in the nonbroadly-sensitized [pretransplant calculated panel reactive antibody (cPRA), <80%] adult deceased donor kidney transplant recipients (adult-DDKTRs) are understudied. In this registry, study of 55 593 adult-DD-KTRs, outcomes of LDAIT [(ATG, N = 32 985) and (ALM, N = 9429)], and IL-2RA (N = 13 179) in <10% and 10-79% cPRA groups was analyzed. Adjusted odds ratio (aOR) of one-year biopsy-proven acute rejection (BPAR) was lower; while, aOR of 1-year composite of re-hospitalization, graft loss, or death was higher with LDAIT than IL2-RA in both cPRA groups. Adjusted odds ratio (aOR) of delayed graft function was higher with LDAIT than IL-2RA in the <10% cPRA group. Adjusted hazard ratio (aHR) of 5-year death-censored graft loss (DCGL) in both <80% cPRA groups seemed higher with ALM than other inductions [(<10% cPRA: ALM versus IL2RA, aHR = 1.11, 95% CI = 1.00-1.23 and ATG versus ALM: aHR = 0.84, 95% CI = 0.77-0.91; 10-79% cPRA: ALM versus IL2RA, aHR = 1.29, 95% CI = 1.02-1.64; and ATG versus ALM, aHR = 0.83, 95% CI = 0.70-0.98)]. Five-year aHR of death did not differ among induction therapies in both cPRA groups. In nonbroadly sensitized adult-DDKTRs, LDAIT is more protective against 1-year BPAR (not 5-year mortality) than IL-2RA; the trend of a higher 5-year DCGL risk with ALM than ATG or IL-2RA needs further investigation.

Outcomes of sirolimus regimens in 65-year-old and older kidney transplant recipients: a registry-based observational study.

PURPOSE: In large observational studies of adult kidney transplant recipients (KTRs) where older adults (65 years old and older) were not well represented, the mammalian target of rapamycin inhibitors (mTOR inhibitors) has poorer outcomes than the standard tacrolimus-mycophenolate-steroids (TAC-MPA-S) regimen. We conducted this study to compare the outcomes of regimens containing the common mTOR inhibitor, sirolimus (SRL) against TAC-MPA-S in older adult KTRs. METHODS: Using the 2000-2016 Scientific Registry of Transplant Recipients, Cox multivariable regression models were conducted to analyze the patient and graft outcomes associated with regimens containing SRL, steroids (S) and cyclosporine (CSA), tacrolimus (TAC), or mycophenolate (MPA) vs. the standard (TAC-MPA-S) regimen in older adult KTRs. RESULTS: Included in the analysis were 15,008 (95.19%) older adult KTRs on standard (TAC-MPA-S) regimen, 242 (1.53%) on SRL-MPA-S, 300 (1.90%) on SRL-TAC-S, and 217 (1.38%) on SRL-CSA-S. Compared with the standard regimen, the adjusted risks of all-cause death and overall graft loss over a maximum 5-year follow-up were highest with SRL-MPA-S, intermediate with SRL-TAC-S and not significantly different with SRL-CSA-S. The adjusted risks of all-cause death and overall graft loss were modified by a pre-transplant history of malignancy in older adult KTRs on SRL-TAC-S, not in those on SRL-MPA-S or SRL-CSA-S. CONCLUSIONS: In older adult kidney transplant recipients, SRL-TAC-S or SRL-MPA-S, but not SRL-CSA-S is associated with higher risks of death and allograft loss than standard TAC-MPA-S regimen and a pre-transplant malignancy history worsens these risks in patients on SRL-TAC-S. Confirmation of our findings by a prospective randomized trial is needed before translation into clinical practice can be recommended.

Postbiopsy arteriovenous fistula in renal allograft: An ultrasound case study.

Arteriovenous fistula is a well-known but rarely diagnosed complication of percutaneous renal biopsy. On Doppler sonography, these fistulae are characterized by a region of high velocity shifts and random color assignment due to vibrating interfaces in the perivascular tissue. Most of them resolve spontaneously, while larger symptomatic ones need intervention.

Not all inflammation in a renal allograft is rejection.

High index of suspicion for adenovirus infection is required in renal graft dysfunction, especially in the setting of hematuria. Histology can mimic acute rejection, which creates a diagnostic dilemma. Tissue adenovirus immunostains, though usually reliable, may not be always positive like in our case.

Fever in a transplant recipient: think beyond infection.

Immune reconstitution inflammatory syndrome (IRIS) is an exaggerated inflammatory cascade initiated in response to immune recovery during the resolution of an infection. Reduction in calcineurin inhibitor levels in organ transplant recipients due to enhanced metabolism from interaction with rifampin can predispose these individuals to develop IRIS during the treatment of tuberculosis and mimic sepsis.

The skin-kidney connection: bullous pemphigoid associated with acute allograft rejection and membranous nephropathy.

Bullous pemphigoid has been linked to allograft rejection, as well as membranous nephropathy in renal transplant recipients. Although there is a possibility of multiple distinct autoimmune processes, immune stimulation induced by allograft rejection or antibasement zone antibody interactions are possible mechanisms for the simultaneous skin and renal involvement.

New-onset diabetes after kidney transplantation: can the risk be modified by choosing immunosuppression regimen based on pretransplant viral serology?

Background: This study aimed to analyze adult kidney transplant recipients (KTRs) for the risk of new-onset diabetes after transplantation (NODAT) associated with viral serologies and immunosuppression regimens [tacrolimus (Tac) + mycophenolate (MPA), cyclosporine (CSA) + MPA, sirolimus (SRL) + MPA, SRL + CSA or SRL +Tac]. Methods: Cox regression models were used to examine the risk of NODAT in the first posttransplant year associated with: (i) CSA + MPA, SRL + MPA, SRL + MPA or SRL + Tac versus reference, Tac + MPA; (ii) pretransplant viral serology [+ or -; hepatitis B core (HBc), hepatitis C (HCV), cytomegalovirus (CMV) or Epstein Barr Virus (EBV)]; and (iii) interactions between immunosuppression regimens and the viral serology found significant in the main analysis. Results: Adult KTRs (n = 97 644) from January 1995 through September 2015 were studied. HCV+ [hazard ratio (HR) 1.50, 95% confidence interval (CI) 1.31-1.68] or CMV+ (HR 1.12, 95% CI 1.06-1.19) serology was a risk factor and HBc+ (HR 1.04, 95% CI 0.95-1.15) or EBV+ (HR 1.06, 95% CI 0.97-1.15) serology was not a risk factor for NODAT. Regardless of associated HCV or CMV serology, risk of NODAT relative to the reference regimen (Tac + MPA) was lower with CSA + MPA [HCV-: HR 0.74, 95% CI 0.65-0.85; HCV+: HR 0.47, 95% CI 0.28-0.78; CMV-: CSA + MPA HR 0.68, 95% CI 0.54-0.86; CMV+: (CSA + MPA) HR 0.73, 95% CI 0.63-0.85] and similar with SRL + CSA or SRL + MPA. In KTRs with HCV- or CMV+ serology, SRL + Tac was associated with a higher risk of NODAT relative to reference [HCV- (HR 1.43, 95% CI 1.17-1.74) and CMV+ (HR 1.44, 95% CI 1.14-1.81), respectively]. The risk for NODAT-free graft loss was lower with Tac + MPA than the other regimens. Conclusions: Tailoring immunosuppression regimen based on HCV or CMV serology may modify the risk of developing NODAT in KTRs.

Association of Baseline Viral Serology and Sirolimus Regimens With Kidney Transplant Outcomes: A 14-Year Registry-Based Cohort Study in the United States.

BACKGROUND: The risks for transplant outcomes associated with baseline viral serostatus in kidney transplant recipients (KTR) on sirolimus have not been widely studied. METHODS: We performed a cohort-study of 61 590 adult KTR in 2000 to 2013. We used Cox regression models to determine the adjusted hazard ratio (aHR) of patient death, death-censored graft loss and posttransplant malignancy associated with the baseline serostatus (+ or -: hepatitis B core [HBc], hepatitis C virus [HCV], Epstein-Barr virus [EBV], or cytomegalovirus [CMV]) in KTR on sirolimus (SRL) + mycophenolate (MPA) or SRL + tacrolimus (Tac), relative to the control-regimen: Tac + MPA. RESULTS: Compared with Tac + MPA, SRL + MPA, and SRL + Tac were associated with higher risks of 5-year mortality (aHR, 1.41; 95% CI, 1.23-1.60 and aHR, 1.59; 95% CI, 1.38-1.83, respectively) and death-censored graft loss (aHR, 1.41; 95% CI, 1.24-1.60 and aHR, 1.38; 95% CI, 1.21-1.57, respectively). In KTR with negative pretransplant EBV, CMV, HBc, or HCV serostatus, SRL + MPA not SRL + Tac was associated with a lower risk of posttransplant malignancy compared with control (aHR, 0.27; 95% CI, 0.10-0.72; aHR, 0.61; 95% CI, 0.43-0.88; aHR, 0.79; 95% CI, 0.64-0.97; and aHR, 0.80; 95% CI, 0.65-0.98, respectively, for SRL + MPA and aHR, 0.98: 95% CI, 0.52-1.80; aHR, 0.69; 95% CI, 0.46-1.06; aHR, 0.83; 95% CI, 0.66-1.06 and aHR, 0.85; 95% CI, 0.67-1.07, respectively, for SRL + Tac). In KTR with positive serostatus to any of the above viruses, SRL + MPA or SRL + Tac was not associated with a different malignancy risk compared with control. CONCLUSIONS: Compared with Tac + MPA, SRL regimens were associated with higher risks for patient death and graft loss, although SRL + MPA was associated with a lower risk for posttransplant malignancy in kidney allograft recipients with negative pretransplant HBc, HCV, EBV, or CMV serology.

Analysis of Risk Factors for Kidney Retransplant Outcomes Associated with Common Induction Regimens: A Study of over Twelve-Thousand Cases in the United States.

We studied registry data of 12,944 adult kidney retransplant recipients categorized by induction regimen received into antithymocyte globulin (ATG) (N = 9120), alemtuzumab (N = 1687), and basiliximab (N = 2137) cohorts. We analyzed risk factors for 1-year acute rejection (AR) and 5-year death-censored graft loss (DCGL) and patient death. Compared with the reference, basiliximab: (1) one-year AR risk was lower with ATG in retransplant recipients of expanded criteria deceased-donor kidneys (HR = 0.56, 95% CI = 0.35-0.91 and HR = 0.54, 95% CI = 0.27-1.08, resp.), while AR risk was lower with alemtuzumab in retransplant recipients with >3 HLA mismatches before transplant (HR = 0.63, 95% CI = 0.44-0.93 and HR = 0.81, 95% CI = 0.63-1.06, resp.); (2) five-year DCGL risk was lower with alemtuzumab, not ATG, in retransplant recipients of African American race (HR = 0.54, 95% CI = 0.34-0.86 and HR = 0.73, 95% CI = 0.51-1.04, resp.) or with pretransplant glomerulonephritis (HR = 0.65, 95% CI = 0.43-0.98 and HR = 0.82, 95% CI = 0.60-1.12, resp.). Therefore, specific risk factor-induction regimen combinations may predict outcomes and this information may help in individualizing induction in retransplant recipients.

Nebivolol Effects on Nitric Oxide Levels, Blood Pressure, and Renal Function in Kidney Transplant Patients.

In hypertensive kidney transplant recipients, the effects of nebivolol vs metoprolol on nitric oxide (NO) blood level, estimated glomerular filtration rate (eGFR), and blood pressure (BP) have not been previously reported. In a 12-month prospective, randomized, open-label, active-comparator trial, hypertensive kidney transplant recipients were treated with nebivolol (n=15) or metoprolol (n=15). Twenty-nine patients (nebivolol [n=14], metoprolol [n=15]) completed the trial. The primary endpoint was change in blood NO level after 12 months of treatment. Secondary endpoints were changes in eGFR, BP, and number of antihypertensive drug classes used. After 12 months of treatment, least squares mean change in plasma NO level in the nebivolol kidney transplant recipient group younger than 50 years was higher by 68.19% (99.17% confidence interval [CI], 13.02-123.36), 69.54% (99.17% CI, 12.71-126.37), and 66.80% (99.17% CI, 12.95-120.64) compared with the metoprolol group younger than 50 years, the metoprolol group 50 years and older, and the nebivolol group 50 years and older, respectively. The baseline to month 12 change in mean arterial BP, eGFR, and number of antihypertensive drug classes used was not significantly different between the treatment groups. In hypertensive kidney transplant recipients, nebivolol use in patients younger than 50 years increased blood NO.

Survival With Dialysis Versus Kidney Transplantation in Adult Hemolytic Uremic Syndrome Patients: A Fifteen-Year Study of the Waiting List.

BACKGROUND: Survival data are lacking for kidney transplant recipients with rare native end-stage renal disease (ESRD) etiologies. There is currently no large registry study comparing dialysis versus kidney transplantation survival outcomes of waitlisted adults with hemolytic uremic syndrome (HUS). MATERIALS AND METHODS: We retrospectively studied adult-HUS end-stage renal disease patients (n = 559) placed on the US kidney transplant waitlist in 1996 to 2011. We analyzed 5-year transplantation and patient survival probabilities and risk factors using Kaplan-Meier and Cox hazards models, respectively. Using similar models, waitlist and transplantation outcomes of patients with diabetes mellitus (DM), hypertension (HTN), and glomerulonephritis (GN) were analyzed, and then compared with HUS patients. RESULTS: Compared with waitlisted adult HUS patients on dialysis, 5-year mortality risks were 73% and 48% lower in recipients of living (hazard ratio [HR], 0.27, 95% confidence interval [95% CI], 0.11-0.65) and standard deceased (HR, 0.52; 95% CI, 0.29-0.94) donor kidney transplants, respectively. Mortality risks over 5 years were 44%, 50%, 54%, and 55% lower in the overall transplant recipient cohorts than in the dialysis-maintained cohorts within the HUS (HR, 0.56; 95% CI, 0.35-0.91), HTN (HR, 0.50; 95% CI, 0.48-0.52), GN (HR, 0.46; 95% CI, 0.44-0.49), and DM (HR, 0.45; 95% CI, 0.44-0.47) groups, respectively. Five-year transplantation probability in the waitlisted HUS cohort was 60% versus 42% to 49% (P < 0.001) in the DM and HTN cohorts, and 62% (P = 0.93) in the GN cohort. CONCLUSIONS: Living and standard criteria deceased donor kidney transplants provide significant survival benefit over dialysis in waitlisted adults with HUS. On the waitlist, the 5-year transplantation probability was higher in HUS than in DM and HTN patients.