The Impact of Cold Ischaemia Time on Outcomes of Living Donor Kidney Transplantation in the UK Living Kidney Sharing Scheme.

OBJECTIVE: To assess the impact of CIT on living donor kidney transplantation (LDKT) outcomes in the UKLKSS versus outside the scheme. BACKGROUND: LDKT provides the best treatment option for end-stage kidney disease patients. end-stage kidney disease patients with an incompatible living donor still have an opportunity to be transplanted through Kidney Exchange Programmes (KEP). In KEPs where kidneys travel rather than donors, cold ischaemia time (CIT) can be prolonged. METHODS: Data from all UK adult LDKT between 2007 and 2018 were analysed. RESULTS: 9969 LDKT were performed during this period, of which 1396 (14%) were transplanted through the UKLKSS, which we refer to as KEP. Median CIT was significantly different for KEP versus non-KEP (339 versus 182 minutes, P < 0.001). KEP LDKT had a higher incidence of delayed graft function (DGF) (2.91% versus 5.73%, P < 0.0001), lower 1-year (estimated Glomerular Filtration Rate (eGFR) 57.90 versus 55.25 ml/min, P = 0.04) and 5-year graft function (eGFR 55.62 versus 53.09 ml/min, P = 0.01) compared to the non-KEP group, but 1- and 5-year graft survival were similar. Within KEP, a prolonged CIT was associated with more DGF (3.47% versus 1.95%, P = 0.03), and lower graft function at 1 and 5-years (eGFR = 55 vs 50 ml/min, P = 0.02), but had no impact on graft survival. CONCLUSION: Whilst CIT was longer in KEP, associated with more DGF and lower graft function, excellent 5-year graft survival similar to non-KEP was found.

Pericardectomy after pericarditis constrictiva led to onset of transplant kidney function after 98 days of anuric kidney graft: a case report.

BACKGROUND: Constrictive pericarditis is easily overlooked and can lead to severe problems in hemodynamics and end-organ perfusion, in our patient leading to 98 days of anuria after living kidney transplantation. This was completely reversible after pericardectomy. CASE PRESENTATION: A 43-year-old female caucasian patient received a living kidney donation from her mother. She had developed end-stage renal disease 2 years prior due to nephrotic syndrome linked to graft-versus-host disease after allogenic stem-cell transplantation for aplastic anemia. The graft showed insufficient function already in the early postoperative phase. Dialysis was paused after surgery, but the patient developed hypervolemia with ascites and edema in the lower extremities. Doppler ultrasonography showed scarce perfusion, with intrarenal arterial waveforms without end-diastolic flow. The venous perfusion profiles showed pulsatile retrograde flow. There was no identifiable reason for a primary vascular perfusion problem on ultrasonography or transplant kidney angiography. Kidney transplant biopsy revealed no rejection but extensive acute tubular necrosis. Three weeks after transplantation, the patient developed an acute anuric graft failure caused by severe cardiac decompensation. Echocardiography revealed a previously unnoticed constrictive pericarditis, which could be confirmed in a cardio computed tomography scan. The constrictive pericarditis had not been apparent on previous x-rays, computed tomography scans, or echocardiographies, including those for transplantation evaluation. Conservative management of the constrictive pericarditis was not successful and the graft remained anuric. Eventually, the patient underwent pericardectomy 16 weeks after kidney transplantation. Shortly after surgery, the graft started urine production again, which significantly increased within a few days. The clearance improved and 2 weeks later, the patient was free from dialysis. CONCLUSIONS: This case illustrates that special attention should be given to the pericardium during transplant evaluation, especially for patients who previously underwent stem-cell transplantations, chemotherapy or radiation.

Comprehensive assessment of deceased donor kidneys with clinical characteristics, pre-implant biopsy histopathology and hypothermic mechanical perfusion parameters is highly predictive of delayed graft function.

Background: Due to the current high demand for transplant tissue, an increasing proportion of kidney donors are considered extended criteria donors, which results in a higher incidence of delayed graft function (DGF) in organ recipients. Therefore, it is important to fully investigate the risk factors of DGF, and establish a prediction system to assess donor kidney quality before transplantation.Methods: A total of 333 donation after cardiac death kidney transplant recipients were included in this retrospective study. Both univariate and multivariate analyses were used to analyze the risk factors of DGF occurrence. Receiver operating characteristic (ROC) curves were used to analyze the predictive value of variables on DGF posttransplant.Results: The donor clinical scores, kidney histopathologic Remuzzi scores and hypothermic mechanical perfusion (HMP) parameters (flow and resistance index) were all correlated. 46 recipients developed DGF postoperatively, with an incidence of 13.8% (46/333). Multivariate logistic regression analysis of the kidney transplants revealed that the independent risk factors of DGF occurrence post-transplantation included donor score (OR = 1.12, 95% CI 1.06-1.19, p < 0.001), Remuzzi score (OR = 1.21, 95% CI 1.02-1.43, p = 0.029) and acute tubular injury (ATI) score (OR = 4.72, 95% CI 2.32-9.60, p < 0.001). Prediction of DGF with ROC curve showed that the area under the curve was increased to 0.89 when all variables (donor score, Remuzzi score, ATI score and HMP resistance index) were considered together.Conclusions: Combination of donor clinical information, kidney pre-implant histopathology and HMP parameters provide a more accurate prediction of DGF occurrence post-transplantation than any of the measures alone.

Canadian survey on the rates of use of intraoperative diuretics and justification for their use during renal allograft reperfusion.

BACKGROUND: Mannitol and furosemide have been used as diuretics intraoperatively to facilitate early renal allograft function and reduce delayed graft function. As the evidence of any efficacy of these agents is limited, we sought to characterize the use of diuretics among transplant surgeons. METHODS: An anonymous online survey was sent to all Canadian transplant programs where kidney transplants are routinely performed. Questions were related to the use and indications for mannitol and furosemide. Responses were collected and analyzed as counts and percentages of respondents. We used χ2 analysis to assess the relationship between demographic factors and survey responses. RESULTS: Thirty-five surgeons completed the survey (response rate 50%). Seventy per cent of respondents reported performing 26 or more transplants per year, 88% had formal transplant fellowship training and 67% indicated that they currently train fellows. Only 24% and 12% reported believing that delayed graft function is reduced by mannitol and furosemide use, respectively. However, 73% routinely gave mannitol to patients and 53% routinely gave furosemide. The most common justification given for mannitol use was to induce diuresis (54%); 37% of respondents reported using mannitol because of training dogma. Likewise, 57% used furosemide for diuresis, with 23% reporting that their use of this agent was based on dogma. No relationship emerged between fellowship training, case volume or training program status and the use of any agent. Interestingly, 71% of respondents indicated that a randomized controlled trial evaluating the utility of intraoperative diuretics is needed and that they were interested in participating in such a trial. CONCLUSION: Use of intraoperative diuretics and the rationale for their use vary among surgeons. A substantial proportion of surgeons use these medications on the basis of dogma alone. A randomized controlled trial is needed to clarify the role of intraoperative diuretics in kidney transplant surgery.

CONTEXTE: On a utilisé le mannitol et le furosémide comme diurétiques peropératoires pour stimuler le fonctionnement précoce de l'allogreffe rénale et réduire le retard de fonctionnement du greffon. Comme les données probantes quant à l'efficacité de ces agents sont limitées, nous avons voulu caractériser l'utilisation des diurétiques chez les chirurgiens qui effectuent ces transplantations. MÉTHODES: Un sondage anonyme en ligne a été envoyé à tous les programmes de greffe canadiens où des greffes rénales sont couramment effectuées. Les questions avaient trait à l'utilisation et aux indications du mannitol et du furosémide. Les réponses ont été recueillies et analysées sous forme de nombres et de pourcentages des répondants. Le test du χ2 a été utilisé pour évaluer le lien entre les facteurs démographiques et les réponses au sondage. RÉSULTATS: Trente-cinq chirurgiens ont répondu au sondage (taux de réponse 50 %). Soixante-dix pour cent des répondants ont indiqué effectuer annuellement 26 greffes ou plus, 88 % avaient suivi une spécialisation formelle pour l'exécution des greffes et 67 % ont dit être en cours de spécialisation. Seulement 24 % et 12 % respectivement ont dit croire que le mannitol et le furosémide permettent de réduire le retard de fonctionnement du greffon. Toutefois, 73 % et 53 % respectivement administraient de routine du mannitol et du furosémide aux patients. La justification la plus fréquente de l'utilisation du mannitol était d'induire la diurèse (54 %); 37 % des répondants ont dit utiliser le mannitol parce que c'est ce qu'on leur a enseigné durant leur formation. De même, 57 % utilisaient le furosémide pour la diurèse, dont 23 % disaient que c'est ce qu'on leur avait enseigné durant leur formation. Aucun lien n'est ressorti entre la spécialisation, le volume de cas ou le statut à l'égard du programme de formation et l'utilisation d'un agent quelconque. Fait à noter, 71 % des répondants ont indiqué qu'un essai randomisé et contrôlé sur l'utilité des diurétiques peropératoires serait nécessaire et qu'ils y participeraient volontiers. CONCLUSION: L'utilisation de diurétiques peropératoires et la justification de leur utilisation varient d'un chirurgien à l'autre. En majeure partie, les chirurgiens utilisent ces médicaments sur la base des notions théoriques seulement. Un essai randomisé et contrôlé s'impose pour clarifier le rôle des diurétiques peropératoires dans la greffe rénale.

Kidney transplant from uncontrolled donation after circulatory death donors maintained by nECMO has long-term outcomes comparable to standard criteria donation after brain death.

Uncontrolled donation after circulatory death (uDCD) increases organ availability for kidney transplant (KT) with short-term outcomes similar to those obtained from donation after brain death (DBD) donors. However, heterogeneous results in the long term have been reported. We compared 10-year outcomes between 237 KT recipients from uDCD donors maintained by normothermic extracorporeal membrane oxygenation (nECMO) and 237 patients undergoing KT from standard criteria DBD donors during the same period at our institution. We further analyzed risk factors for death-censored graft survival in the uDCD group. Delayed graft function (DGF) was more common in the uDCD group (73.4% vs 46.4%; P < .01), although glomerular filtration rates at the end of follow-up were similar in the 2 groups. uDCD and DBD groups had similar rates for 10-year death-censored graft (82.1% vs 80.4%; P = .623) and recipient survival (86.2% vs 87.6%; P = .454). Donor age >50 years was associated with graft loss in the uDCD group (hazard ratio: 1.91; P = .058), whereas the occurrence of DGF showed no significant effect. uDCD KT under nECMO support resulted in similar graft function and long-term outcomes compared with KT from standard criteria DBD donors. Increased donor age could negatively affect graft survival after uDCD donation.

The Neglectable Impact of Delayed Graft Function on Long-term Graft Survival in Kidneys Donated After Circulatory Death Associates With Superior Organ Resilience.

OBJECTIVE: To explore putative different impacts of delayed graft function (DGF) on long-term graft survival in kidneys donated after brain death (DBD) and circulatory death (DCD). BACKGROUND: Despite a 3-fold higher incidence of DGF in DCD grafts, large studies show equivalent long-term graft survival for DBD and DCD grafts. This observation implies a differential impact of DGF on DBD and DCD graft survival. The contrasting impact is remarkable and yet unexplained. METHODS: The impact of DGF on DBD and DCD graft survival was evaluated in 6635 kidney transplants performed in The Netherlands. DGF severity and functional recovery dynamics were assessed for 599 kidney transplants performed at the Leiden Transplant Center. Immunohistochemical staining, gene expression profiling, and Ingenuity Pathway Analysis were used to identify differentially activated pathways in DBD and DCD grafts. RESULTS: While DGF severely impacted 10-year graft survival in DBD grafts (HR 1.67; P < 0.001), DGF did not impact graft survival in DCD grafts (HR 1.08; P = 0.63). Shorter dialysis periods and superior posttransplant eGFRs in DBD grafts show that the differential impact was not caused by a more severe DGF phenotype in DBD grafts. Immunohistochemical evaluation indicates that pathways associated with tissue resilience are present in kidney grafts. Molecular evaluation showed selective activation of resilience-associated pathways in DCD grafts. CONCLUSIONS: This study shows an absent impact of DGF on long-term graft survival in DCD kidneys. Molecular evaluation suggests that the differential impact of DGF between DBD and DCD grafts relates to donor-type specific activation of resilience pathways in DCD grafts.

A single-center analysis of early readmission after renal transplantation.

BACKGROUND: Thirty-day readmission rates (early hospital readmission, EHR) are an important benchmark for quality improvement. Nationally, patients undergoing renal transplantation incur a 31% EHR rate. While national databases provide useful data, the impact of EHR on individual centers has received little attention. We proposed that an institutional review of EHR after renal transplantation may provide a benchmark for individual transplant programs and identify modifiable program-specific issues to reduce EHR. METHODS: We reviewed 269 consecutive kidney transplant recipients over a five-year period (2012-2016). Early hospital readmission was modeled using generalized linear modeling assuming a binary distribution. RESULTS: About 21% of patients were readmitted within 30 days. Deceased kidney donation (DD), delayed graft functioning (DGF), anti-thymocyte globulin (ATG) induction, diabetes, public insurance, weekend discharge, and low glomerular filtration rate (eGFR) at discharge were all identified as risk factors for readmission. Early hospital readmission was not correlated with risk of death (5.4% at 44 months: HR 2.2 (95% CI [0.7, 6.6]; P = 0.1473) or graft loss. CONCLUSIONS: EHR after renal transplantation is common. Certain factors may predict an increased risk for EHR. A multi-disciplinary approach to discharge planning may limit some EHR, but most complications and adverse events are unpredictable and require hospital-level of care.

Factors predicting kidney delayed graft function among recipients of simultaneous liver-kidney transplantation: A single-center experience.

BACKGROUND: Kidney delayed graft function (kDGF) remains a challenging problem following simultaneous liver and kidney transplantation (SLKT) with a reported incidence up to 40%. Given the scarcity of renal allografts, it is crucial to minimize the development of kDGF among SLKT recipients to improve patient and graft outcomes. We sought to assess the role of preoperative recipient and donor/graft factors on developing kDGF among recipients of SLKT. METHODS: A retrospective review of 194 patients who received SLKT in the period from January 2004 to March 2017 in a single center was performed to assess the effect of preoperative factors on the development of kDGF. RESULTS: Kidney delayed graft function was observed in 95 patients (49%). Multivariate analysis revealed that donor history of hypertension, cold static preservation of kidney grafts [versus using hypothermic pulsatile machine perfusion (HPMP)], donor final creatinine, physiologic MELD, and duration of delay of kidney transplantation after liver transplantation were significant independent predictors for kDGF. kDGF is associated with worse graft function and patient and graft survival. CONCLUSIONS: Kidney delayed graft function has detrimental effects on graft function and graft survival. Understanding the risks and combining careful perioperative patient management, proper recipient selection and donor matching, and graft preservation using HPMP would decrease kDGF among SLKT recipients.

Duration of delayed graft function and outcomes after kidney transplantation from controlled donation after circulatory death donors: a retrospective study.

The impact of the duration of delayed graft function (DGF) on graft survival is poorly characterized in controlled donation after circulatory death (DCD) donor kidney transplantation. A retrospective analysis was performed on 225 DCD donor kidney transplants between 2011 and 2016. When patients with primary nonfunction were excluded (n = 9), 141 recipients (65%) had DGF, with median (IQR) duration of dialysis dependency of 6 (2-11.75) days. Longer duration of dialysis dependency was associated with lower estimated glomerular filtration rate at 1 year, and a higher rate of acute rejection. On Kaplan-Meier analysis, the presence of DGF was associated with lower graft survival (log-rank test P = 0.034), though duration of DGF was not (P = 0.723). However, multivariable Cox regression analysis found that only acute rejection was independently associated with lower graft survival [HR (95% CI) 4.302 (1.617-11.450); P = 0.003], whereas the presence of DGF and DGF duration were not. In controlled DCD kidney transplantation, DGF duration itself may not be independently associated with graft survival; rather, it may be that acute rejection associated with prolonged DGF is the poor prognostic factor.

Ischaemia reperfusion injury: mechanisms of progression to chronic graft dysfunction.

The increasing use of extended criteria organs to meet the demand for kidney transplantation raises an important question of how the severity of early ischaemic injury influences long-term outcomes. Significant acute ischaemic kidney injury is associated with delayed graft function, increased immune-associated events and, ultimately, earlier deterioration of graft function. A comprehensive understanding of immediate molecular events that ensue post-ischaemia and their potential long-term consequences are key to the discovery of novel therapeutic targets. Acute ischaemic injury primarily affects tubular structure and function. Depending on the severity and persistence of the insult, this may resolve completely, leading to restoration of normal function, or be sustained, resulting in persistent renal impairment and progressive functional loss. Long-term effects of acute renal ischaemia are mediated by several mechanisms including hypoxia, HIF-1 activation, endothelial dysfunction leading to vascular rarefaction, sustained pro-inflammatory stimuli involving innate and adaptive immune responses, failure of tubular cells to recover and epigenetic changes. This review describes the biological relevance and interaction of these mechanisms based on currently available evidence.

Association of baseline histopathology and kidney donor risk index with graft outcomes in deceased donor kidney transplantation
.

BACKGROUND: Donor organ quality is a key determinant of graft outcomes in deceased donor kidney transplantation (DDKT). The predictive values of baseline histopathology and several clinical scoring systems for long-term graft outcomes have been evaluated, but the results remain controversial. MATERIALS AND METHODS: We screened 167 patients who underwent DDKT at Ulsan University Hospital from April 2003 to June 2016. Among them, 66 patients who underwent baseline kidney biopsy and whose kidney donor risk index (KDRI) was available were included in this analysis. All baseline biopsies were rescored according to the updated Banff classification. RESULTS: Median follow-up was 22 months. Mean age of recipients and donors was 51.4 and 44.7 years, respectively. Mean KDRI was 1.40 ± 0.44. During follow-up, delayed graft function and biopsy-proven acute rejection (BPAR) developed in 7 and 11 patients, respectively. Graft failure occurred in 2 patients. In Cox regression analysis, interstitial fibrosis/tubular atrophy (IFTA) (hazard ratio (HR) = 3.59; p = 0.049) was a significant risk factor for BPAR. In multivariate linear regression, age (standardized ß (SB) = -0.282; p = 0.002), BPAR (SB = -0.406; p < 0.001), KDRI (SB = -0.277; p = 0.003), and IFTA (SB = -0.298; p = 0.001) were significant predictors of last-visit estimated glomerular filtration rate (eGFR). CONCLUSION: Several clinical and pathologic parameters, such as KDRI and IFTA, may be helpful for predicting long-term graft outcomes, including BPAR and last-visit eGFR, in DDKT.
.

Comparison of graft and patient outcomes following kidney transplantation in extended hour and conventional haemodialysis patients.

AIM: Differences in early graft function between kidney transplant recipients previously managed with either haemodialysis (HD) or peritoneal dialysis are well described. However, only two single-centre studies have compared graft and patient outcomes between extended hour and conventional HD patients, with conflicting results. METHODS: This study compared the outcomes of all extended hour (≥24 h/week) and conventional HD patients transplanted in Australia and New Zealand between 2000 and 2014. The primary outcome was delayed graft function (DGF), defined in an ordinal manner as either a spontaneous fall in serum creatinine of less than 10% within 24 h, or the need for dialysis within 72 h following transplantation. Secondary outcomes included the requirement for dialysis within 72 h post-transplant, acute rejection, estimated glomerular filtration rate at 12 months, death-censored graft failure, all-cause and cardiovascular mortality, and a composite of graft failure and mortality. RESULTS: A total of 4935 HD patients (378 extended hour HD, 4557 conventional HD) received a kidney transplant during the study period. Extended hour HD was associated with an increased likelihood of DGF compared with conventional HD (adjusted proportional odds ratio 1.33; 95% confidence interval 1.06-1.67). There was no significant difference between extended hour and conventional HD in terms of any of the secondary outcomes. CONCLUSION: Compared to conventional HD, extended hour HD was associated with DGF, although long-term graft and patient outcomes were not different.

Impact of acute kidney injury in expanded criteria deceased donors on post-transplant clinical outcomes: multicenter cohort study.

BACKGROUND: The problem of organ shortage is an important issue in kidney transplantation, but the effect of kidney donation on AKI is unclear. The aim of this study was to investigate the impact of acute kidney injury (AKI) on post-transplant clinical outcomes for deceased donor kidney transplantation (DDKT) using standard criteria donors (SCDs) versus expanded criteria donors (ECDs). METHODS: Five-hundred nine KT recipients receiving kidneys from 386 deceased donors (DDs) were included from three transplant centers. Recipients were classified into the SCD-KT or ECD-KT group according to corresponding DDs and both groups were divided into the AKI-KT or non-AKI-KT subgroups according to AKI in donor. We compared the clinical outcomes among those four groups and investigated the interaction between AKI in donors and ECD on allograft outcome. RESULTS: The incidence of delayed allograft function was higher when the donors had AKI within SCD-KT and ECD-KT groups. In allograft biopsies within 3 months, chronic change was more significant in the AKI-ECD-KT subgroup than in the non-AKI-ECD-KT subgroup, but it did not differ between AKI-SCD-KT and non-AKI-SCD-KT group. AKI-ECD-KT showed higher risk for death-censored allograft failure than the other three groups and a significant interaction was observed between AKI in donors and ECD on the allograft outcome. CONCLUSIONS: The presence of AKI in ECDs significantly impacted the long-term allograft outcomes of kidney transplant recipients, but it did not in SCDs.

Predicting urine output after kidney transplantation: development and internal validation of a nomogram for clinical use.

PURPOSE: To analyze pre-transplantation and early postoperative factors affecting post-transplantation urine output and develop a predictive nomogram. PATIENTS AND METHODS: Retrospective analysis of non-preemptive first transplanted adult patients between 2001-2016. The outcomes were hourly diuresis in mL/Kg in the 1st (UO1) and 8th (UO8) postoperative days (POD). Predictors for both UO1 and UO8 were cold ischemia time (CIT), patient and donor age and sex, HLA I and II compatibility, pre-transplantation duration of renal replacement therapy (RRT), cause of ESRD (ESRD) and immunosuppressive regimen. UO8 predictors also included UO1, 1st/0th POD plasma creatinine concentration ratio (Cr1/0), and occurrence of acute cellular rejection (AR). Multivariable linear regression was employed to produce nomograms for UO1 and UO8. RESULTS: Four hundred and seventy-three patients were included, mostly deceased donor kidneys' recipients (361, 70.4%). CIT inversely correlated with UO1 and UO8 (Spearman's p=-0.43 and -0.37). CR1/0 inversely correlated with UO8 (p=-0.47). On multivariable analysis UO1 was mainly influenced by CIT, with additional influences of donor age and sex, HLA II matching and ESRD. UO1 was the strongest predictor of UO8, with significant influences of AR and ESRD. CONCLUSIONS: The predominant influence of CIT on UO1 rapidly wanes and is replaced by indicators of functional recovery (mainly UO1) and allograft's immunologic acceptance (AR absence). Mean absolute errors for nomograms were 0.08 mL/Kg h (UO1) and 0.05 mL/Kg h (UO8).

Association between Early Resistive Index Measurement and Early Graft Function and Long-Term Graft Survival after Kidney Transplantation: an Evidence-based Clinical Review.

BACKGROUND: resistive index (RI) is highly utilised to assess the graft function using Doppler ultrasonography. The RI has been shown as the best ultrasound parameter to assess kidney allograft dysfunction. Several studies have established the role of the RI as a predictor of transplant failure. However, these studies were using RI measurement in the later stages post transplantation. The present study has conducted to identify the association between early RI measurement and early graft function represented as delayed graft function (DGF) and immediate graft function (IGF), as well as long-term graft survival. METHODS: an evidence-based clinical review of studies published before May 2018 was conducted from Medline, Science Direct, EMBASE and Cochrane databases. Studies on early measurement of RI whereby the primary or secondary goals of the study related to graft function and/or graft survival were included. Studies using late RI measurement and without RI value groups were excluded. The Mantzel-Haenzel method was used to analyse pooled risk ratio and 95% confidence interval, while the heterogeneity of the study was calculated through I2 value. Data analysis was performed using Review Manager 5.3. RESULTS: nine studies with a total of 1802 patients who had undergone a kidney transplant were analysed. DGF was found in 19% (193/1015) of the low RI group and in 42.8% (337/787) of the high RI group (RR 2.04 (95% CI 1.72 - 2.41), p < 0.00001, I2 = 28%). IGF was found in 39.5% (62/157) of the low RI group and in 10.5% (28/268) of the high RI group (RR 0.26 (95% CI 0.17 - 0.40), p < 0.00001, I2 = 0%). Long-term graft survival, with follow up between 60-144 months, was found in 83% (701/845) of the low RI group and in 69.4% (395/569) of the high RI group (RR 0.82 (95% CI 0.72 - 0.93), p = 0.002, I2 = 63%). CONCLUSION: the results of this study emphasise the association between early measurement of RI and early graft function, and long-term graft survival. An elevated RI provides the chance of recognizing the patients with poor long-term prognosis, from the first moment after kidney transplant.

Machine perfusion and long-term kidney transplant recipient outcomes across allograft risk strata.

Background: The use of machine perfusion (MP) in kidney transplantation lowers delayed graft function (DGF) and improves 1-year graft survival in some, but not all, grafts. These associations have not been explored in grafts stratified by the Kidney Donor Profile index (KDPI). Methods: We analyzed 78 207 deceased-donor recipients using the Scientific Registry of Transplant Recipients data from 2006 to 2013. The cohort was stratified using the standard criteria donor/expanded criteria donor (ECD)/donation after cardiac death (DCD)/donation after brain death (DBD) classification and the KDPI scores. In each subgroup, MP use was compared with cold storage. Results: The overall DGF rate was 25.4% and MP use was associated with significantly lower DGF in all but the ECD-DCD donor subgroup. Using the donor source classification, the use of MP did not decrease death-censored graft failure (DCGF), except in the ECD-DCD subgroup from 0 to 1 year {adjusted hazard ratio [aHR] 0.56 [95% confidence interval (CI) 0.32-0.98]}. In the ECD-DBD subgroup, higher DCGF from 1 to 5 years was noted [aHR 1.15 (95% CI 1.01-1.31)]. Also, MP did not lower all-cause graft failure except in the ECD-DCD subgroup from 0 to 1 year [aHR = 0.59 (95% CI 0.38-0.91)]. Using the KDPI classification, MP did not lower DCGF or all-cause graft failure, but in the ≤70 subgroup, higher DCGF [aHR 1.16 (95% CI 1.05-1.27)] and higher all-cause graft failure [aHR 1.10 (95% CI 1.02-1.18)] was noted. Lastly, MP was not associated with mortality in any subgroup. Conclusions: Overall, MP did not lower DCGF. Neither classification better risk-stratified kidneys that have superior graft survival with MP. We question their widespread use in all allografts as an ideal approach to organ preservation.

The prognostic value of the furosemide stress test in predicting delayed graft function following deceased donor kidney transplantation.

OBJECTIVES AND METHODS: The Furosemide Stress Test (FST) is a novel dynamic assessment of tubular function that has been shown in preliminary studies to predict patients who will progress to advanced stage acute kidney injury, including those who receive renal replacement therapy (RRT). The aim of this study is to investigate if the urinary response to a single intraoperative dose of intravenous furosemide predicts delayed graft function (DGF) in patients undergoing deceased donor kidney transplant. RESULTS: On an adjusted multiple logistic regression, a single 100 mg dose of intraoperative furosemide after the anastomosis of the renal vessels (FST) predicted the need for RRT at 2 and 6 h post kidney transplantation (KT). Recipient urinary output was measured at 2 and 6 h post furosemide administration. In receiver-operating characteristic (ROC) analysis, the FST predicted DGF with an area-under-the curve of 0.85 at an optimal urinary output cut-off of <600 mls at 6 h with a sensitivity of and a specificity of 83% and 74%, respectively. CONCLUSIONS: The FST is a predictor of DGF post kidney transplant and has the potential to identify patients requiring RRT early after KT.

N-acetylcysteine decreases urinary level of neutrophil gelatinase-associated lipocalin in deceased-donor renal transplant recipients: a randomized clinical trial.

CONTEXT: Acute kidney injury (AKI) is a common complication after kidney transplantation (KT), especially in recipients from deceased donors. Urinary neutrophil gelatinase-associated lipocalin (u-NGAL) is an early and sensitive marker of AKI after transplantation. OBJECTIVES: We assessed the renoprotective effect of N-acetylcysteine (NAC) on u-NGAL levels as an early prognostic marker of graft function immediately after transplantation. MATERIALS AND METHODS: A double-blind, randomized, placebo-controlled trial was conducted on 70 deceased-donor KT recipients ( www.irct.ir , trial registration number: IRCT2014090214693N4). Patients received 600 mg oral NAC or placebo twice daily from day 0 to 5 and urine samples were taken before, and on the first and fifth days after transplantation. U-NGAL and early graft function were compared between the two groups. RESULTS: NAC significantly reduced u-NGAL levels compared to placebo (p value = 0.02), while improvement in early graft function with NAC did not reach statistical significance. CONCLUSIONS: This study showed that NAC administration in deceased-donor KT recipients can reduce tubular kidney injury, evidenced by u-NGAL measurements. Improvement in early graft function needs a larger sample size to reach a statistical conclusion.

Effect of BMI on allograft function and survival in pediatric renal transplant recipients.

OBJECTIVE: To determine whether pre-transplant body mass index (BMI) affects renal allograft function and survival in pediatric renal transplant recipients. STUDY DESIGN: This is a retrospective cohort study using the Organ Procurement and Transplantation Network data from 2000 to 2013 to compare time to total allograft loss (allograft failure or death), prevalence of delayed graft function, prevalence of acute rejection, and estimated glomerular filtration rate (eGFR) post-transplant in pediatric renal transplant recipients categorized by BMI z-score. RESULTS: A total of 8804 kidney transplant recipients met our inclusion criteria, and of those, 6% were underweight, 14% were overweight, and 17% were obese pre-transplant. The adjusted hazard ratio (HR) for allograft failure was significantly higher for obese recipients compared to normal weight recipients (HR 1.25, 95% CI 1.1, 1.42); for every 1 point increase in BMI z-score, there was a 7% increased hazard of allograft failure (HR 1.07; 95% CI 1.03-1.1, p < 0.001). The prevalence of delayed graft function and acute rejection increased with higher BMI z-score category; however, this difference did not reach statistical significance. eGFR at 1 and 5 years post-transplant decreased with higher BMI z-score although it was only statistically significant at 1 year. CONCLUSIONS: Obesity is prevalent in pediatric renal transplant recipients, and obese, but not overweight or underweight, pediatric renal transplant recipients have an increased risk of allograft failure. Implementation of effective obesity interventions in pediatric renal transplant recipients is of critical importance to improve longevity of the renal allograft.

Outcomes of underweight, overweight, and obese pediatric kidney transplant recipients.

BACKGROUND: Obesity is a risk factor for poor transplant outcomes in the adult population. The effect of pre-transplant weight on pediatric kidney transplantation is conflicting in the existing literature. METHODS: Data was collected from the Organ Procurement and Transplantation Network (OPTN) database on recipients aged 2-21 years who received a kidney-only transplant from 1987 to 2017. Recipients were categorized into underweight, normal, overweight, and obese cohorts. Using adjusted regression models, the relationship between recipient weight and various graft outcomes (delayed graft function [DGF], acute rejection, prolonged hospitalization, graft failure, mortality) was examined. RESULTS: 18,261 transplant recipients (mean age 14.1 ± 5.5 years) were included, of which 8.7% were underweight, 14.8% were overweight, and 15% were obese. Obesity was associated with greater odds of DGF (OR 1.3 95% CI 1.13-1.49, p < 0.001), acute rejection (OR 1.23 95% CI 1.06-1.43, p < 0.01), and prolonged hospitalization (OR 1.35 95% CI 1.17-1.54, p < 0.001) as well as greater hazard of graft failure (HR 1.13 95% CI 1.05-1.22, p = 0.001) and mortality (HR 1.19 95% CI 1.05-1.35, p < 0.01). The overweight cohort had an increased risk of graft failure (HR 1.08 95% CI 1.001-1.16, p = 0.048) and increased odds of DGF (OR 1.2 95% CI 1.04-1.38, p = 0.01) and acute rejection (OR 1.18 95% CI 1.01-1.38, p = 0.04). When stratified by age group, the increased risk was realized among younger and older age groups for obese and overweight. Underweight had lower risk of 1-year graft failure (HR 0.82 95% CI 0.71-0.94, p < 0.01), overall graft failure in the 13-17-yr. age group (HR 0.84 95% CI 0.72-0.99, p = 0.03) and acute rejection in the 2-5-yr. age group (OR 0.24 95% CI 0.09-0.66, p < 0.01). CONCLUSION: Pre-transplant weight status and age impact pediatric kidney transplant outcomes. Recipient underweight status seems to be protective against adverse outcomes while overweight and obesity may lead to poorer graft and patient outcomes.