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.

Synergistic impact of pre-sensitization and delayed graft function on allograft rejection in deceased donor kidney transplantation.

The aim of this study is to investigate whether or not delayed graft function (DGF) and pre-transplant sensitization have synergistic adverse effects on allograft outcome after deceased donor kidney transplantation (DDKT) using the Korean Organ Transplantation Registry (KOTRY) database, the nationwide prospective cohort. The study included 1359 cases between May 2014 and June 2019. The cases were divided into 4 subgroups according to pre-sensitization and the development of DGF post-transplant [non-pre-sensitized-DGF(-) (n = 1097), non-pre-sensitized-DGF(+) (n = 127), pre-sensitized-DGF(-) (n = 116), and pre-sensitized-DGF(+) (n = 19)]. We compared the incidence of biopsy-proven allograft rejection (BPAR), time-related change in allograft function, allograft or patient survival, and post-transplant complications across 4 subgroups. The incidence of acute antibody-mediated rejection (ABMR) was significantly higher in the pre-sensitized-DGF(+) subgroup than in other 3 subgroups. In addition, multivariable cox regression analysis demonstrated that pre-sensitization combined with DGF is an independent risk factor for the development of acute ABMR (hazard ratio 4.855, 95% confidence interval 1.499-15.727). Moreover, DGF and pre-sensitization showed significant interaction (p-value for interaction = 0.008). Pre-sensitization combined with DGF did not show significant impact on allograft function, and allograft or patient survival. In conclusion, the combination of pre-sensitization and DGF showed significant synergistic interaction on the development of allograft rejection after DDKT.

Parathyroidectomy or cinacalcet: Do we still not know the best option for graft function in kidney-transplanted patients? A meta-analysis.

BACKGROUND: Tertiary hyperparathyroidism occurs in 25% to 50% of kidney-transplanted patients. Indication of parathyroidectomy is now discussed, since the calcimimetic agent, cinacalcet, is an alternate option. The effects of either of these treatments on graft function remain controversial, studied only in small cohorts showing either decrease or absence of modification. We performed a meta-analysis to evaluate the evolution of graft function after surgical or medical treatment. METHODS: Studies assessing graft function in tertiary hyperparathyroidism after parathyroidectomy or cinacalcet introduction were enrolled into quantitative analysis using Pubmed, Embase, and Cochrane databases following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis reporting guidelines. Among 68 screened studies, 18 had no missing data and were included for statistical analyses. We performed random effect meta-analysis to determine changes in serum creatinine and estimated glomerular filtration rate. RESULTS: Seven studies assessing the evolution of graft function 6 and/or 12 months after parathyroidectomy and 13 after administration of cinacalcet were included. Meta-analysis found no significant variations after parathyroidectomy in serum creatinine (6 studies, 314 patients) and estimated glomerular filtration rate (2 studies, 105 patients). No significant variation was found after administration of cinacalcet in serum creatinine (10 studies, 404 patients) and estimated glomerular filtration rate (6 studies, 149 patients). A significant heterogeneity between the studies (P < .01, Cochran's Q) was found. CONCLUSION: Meta-analysis shows that parathyroidectomy and cinacalcet do not significantly impair graft function in patients with tertiary hyperparathyroidism. However, the significant heterogeneity between selected studies, partially explained by the lack of consensual definition of tertiary hyperparathyroidism, limits the conclusions of all previously published series.

Uromodulin to Osteopontin Ratio in Deceased Donor Urine Is Associated With Kidney Graft Outcomes.

BACKGROUND: Deceased-donor kidneys experience extensive injury, activating adaptive and maladaptive pathways therefore impacting graft function. We evaluated urinary donor uromodulin (UMOD) and osteopontin (OPN) in recipient graft outcomes. METHODS: Primary outcomes: all-cause graft failure (GF) and death-censored GF (dcGF). Secondary outcomes: delayed graft function (DGF) and 6-month estimated glomerular filtration rate (eGFR). We randomly divided our cohort of deceased donors and recipients into training and test datasets. We internally validated associations between donor urine UMOD and OPN at time of procurement, with our primary outcomes. The direction of association between biomarkers and GF contrasted. Subsequently, we evaluated UMOD:OPN ratio with all outcomes. To understand these mechanisms, we examined the effect of UMOD on expression of major histocompatibility complex II in mouse macrophages. RESULTS: Doubling of UMOD increased dcGF risk (adjusted hazard ratio [aHR], 1.1; 95% confidence interval [CI], 1.02-1.2), whereas OPN decreased dcGF risk (aHR, 0.94; 95% CI, 0.88-1). UMOD:OPN ratio ≤3 strengthened the association, with reduced dcGF risk (aHR, 0.57; 0.41-0.80) with similar associations for GF, and in the test dataset. A ratio ≤3 was also associated with lower DGF (aOR, 0.73; 95% CI, 0.60-0.89) and higher 6-month eGFR (adjusted ß coefficient, 3.19; 95% CI, 1.28-5.11). UMOD increased major histocompatibility complex II expression elucidating a possible mechanism behind UMOD's association with GF. CONCLUSIONS: UMOD:OPN ratio ≤3 was protective, with lower risk of DGF, higher 6-month eGFR, and improved graft survival. This ratio may supplement existing strategies for evaluating kidney quality and allocation decisions regarding deceased-donor kidney transplantation.

Renal Function Improvement Following ANG-3777 Treatment in Patients at High Risk for Delayed Graft Function After Kidney Transplantation.

BACKGROUND: Patients (20%-50%) undergoing renal transplantation experience acute kidney injury resulting in delayed graft function. ANG-3777 is an hepatocyte growth factor mimetic that binds to the c-MET receptor. In animal models, ANG-3777 decreases apoptosis, increases proliferation, and promotes organ repair and function. METHODS: This was a randomized, double-blind, placebo-controlled, phase 2 trial of patients undergoing renal transplantation with <50 cc/h urine output for 8 consecutive hours over the first 24 hours posttransplantation, or creatinine reduction ratio <30% from pretransplantation to 24 hours posttransplantation. Subjects were randomized as 2:1 to 3, once-daily IV infusions of ANG-3777, 2 mg/kg (n = 19), or placebo (n = 9). Primary endpoint: time in days to achieve ≥1200 cc urine for 24 hours. RESULTS: Patients treated with ANG-3777 were more likely to achieve the primary endpoint of 1200 cc urine for 24 hours by 28 days posttransplantation (83.3% versus 50% placebo; log-rank test: χ2 = 2.799, P = 0.09). Compared with placebo, patients in the ANG-3777 arm had larger increases in urine output; lower serum creatinine; greater reduction in C-reactive protein and neutrophil gelatinase-associated lipocalin; fewer dialysis sessions and shorter duration of dialysis; fewer hospital days; significantly less graft failure; and higher estimated glomerular filtration rate. Adverse events occurred in a similar percentage of subjects in both arms. Events per subject were twice as high in the placebo arm. CONCLUSIONS: There was an efficacy signal for improved renal function in subjects treated with ANG-3777 relative to placebo, with a good safety profile.

The Association Between Macroscopic Arteriosclerosis of the Renal Artery, Microscopic Arteriosclerosis, Organ Discard, and Kidney Transplant Outcome.

BACKGROUND: During organ retrieval, surgeons estimate the degree of arteriosclerosis and this plays an important role in decisions on organ acceptance. Our study aimed to elucidate the association between macroscopic renal artery arteriosclerosis, donor kidney discard, and transplant outcome. METHODS: We selected all transplanted and discarded kidneys in the Netherlands between January 1, 2000, and December 31, 2015, from deceased donors aged 50 y and older, for which data on renal artery arteriosclerosis were available (n = 2610). The association between arteriosclerosis and kidney discard, the relation between arteriosclerosis and outcome, and the correlation between macroscopic and microscopic arteriosclerosis were explored. RESULTS: Macroscopic arteriosclerosis was independently associated with kidney discard (odds ratio [OR], 1.36; 95% confidence interval [CI], 1.02-1.80; P = 0.03). Arteriosclerosis (any degree) was not significantly associated with delayed graft function (OR, 1.16; 95% CI, 0.94-1.43; P = 0.16), estimated glomerular filtration rate 1-y posttransplant (B, 0.58; 95% CI, -2.07 to 3.22; P = 0.67), and long-term graft survival (hazard ratio, 1.07; 95% CI, 0.86-1.33; P = 0.55). There was a significant association between mild arteriosclerosis and primary nonfunction (OR, 2.14; 95% CI, 1.19-3.84; P = 0.01). We found no correlation between macroscopic and histological arteriosclerosis, nor between histological arteriosclerosis and transplant outcome. CONCLUSIONS: Macroscopic arteriosclerosis of the renal artery was independently associated with kidney discard and somewhat associated with primary nonfunction posttransplant. However, there was no effect of arteriosclerosis on delayed graft function, estimated glomerular filtration rate at 1 y, or long-term graft survival. Our results are valid only after inevitable exclusion of discarded kidneys that had on average more arteriosclerosis. Hence, conclusions should be interpreted in the light of this potential bias.

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.

A Single-Center Assessment of Delayed Graft Function in Recipients of Simultaneous Liver and Kidney Transplant.

BACKGROUND: The effects of delayed graft function on long-term kidney allograft outcomes are poorly defined among simultaneous liver and kidney transplant recipients. METHODS: We analyzed data of all simultaneous liver and kidney recipients transplanted at the University of Wisconsin between 2010 and 2017. Risk factors for the development of delayed graft function, kidney graft failure, and patient mortality were outcomes of interest. RESULTS: There were a total of 60 simultaneous liver and kidney recipients; 28 (47%) had delayed graft function. After adjustment for multiple variables, we found that pretransplant dialysis >6 weeks (hazard ratio [HR] = 5.6, 95% CI: 1.23-25.59, P = .02), pretransplant albumin <3 g/dL (HR = 5.75, 95% CI: 1.76-16.94, P = .003), and presence of pretransplant diabetes (HR = 2.5, 95% CI: 0.97-4.77, P = .05) were significantly associated with delayed graft function. Multivariate analysis showed that pretransplant albumin <3 (HR = 4.86, 95% CI: 1.07-22.02, P = .02) was associated with a higher risk of all-cause kidney allograft failure, whereas the duration of delayed graft function (HR = 1.07 per day, 95% CI: 1.01-1.14, P = .01) was associated with a higher risk of death-censored kidney allograft failure. The presence of delayed graft function was not associated with all-cause or death-censored kidney or liver allograft failure. Similarly, the presence of delayed graft function was not associated with patient mortality. CONCLUSION: The incidence of delayed graft function was high in simultaneous liver and kidney recipients. However, with appropriate management, delayed graft function may not have a negative impact on patient or kidney allograft survival.

A Review of Donor Acute Kidney Injury and Posttransplant Outcomes.

Although over 90 000 people are on the kidney transplant waitlist in the United States, some kidneys that are viable for transplantation are discarded. Transplant surgeons are more likely to discard deceased donors with acute kidney injury (AKI) versus without AKI (30% versus 18%). AKI is defined using changes in creatinine from baseline. Transplant surgeons can use DonorNet data, including admission, peak, and terminal serum creatinine, and biopsy data when available to differentiate kidneys with AKI from those with chronic injury. Although chronic kidney disease is associated with reduced graft survival, an abundance of literature has demonstrated similar graft survival for deceased donors with AKI versus donors without AKI. Donors with AKI are more likely to undergo delayed graft function but have similar long-term outcomes as donors without AKI. The mechanism for similar graft survival is unclear. Some hypothesized mechanisms include (1) ischemic preconditioning; (2) posttransplant and host factors playing a greater role in long-term survival than donor factors; and (3) selection bias of transplanting only relatively healthy donor kidneys with AKI. Existing literature suggests transplanting more donor kidneys with stage 1 and 2 AKI, and cautious utilization of stage 3 AKI donors, may increase the pool of viable kidneys. Doing so can reduce the number of people who die on the waitlist by over 500 every year.

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.

A Propensity Score-weighted Comparison of Outcomes Between Living and Standard Criteria Deceased Donor Kidney Transplant Recipients.

BACKGROUND: Consider a theoretical situation in which 2 patients with similar baseline characteristics receive a kidney transplant on the same day: 1 from a standard criteria deceased donor, the other from a living donor. Which kidney transplant will last longer? METHODS: We conducted a population-based cohort study using linked administrative healthcare databases from Ontario, Canada, from January 1, 2005, to March 31, 2014, to evaluate several posttransplant outcomes in individuals who received a kidney transplant from a standard criteria deceased donor (n = 1523) or from a living donor (n = 1373). We used PS weighting using overlap weights, a novel weighting method that emphasizes the population of recipients with the most overlap in baseline characteristics. RESULTS: Compared with recipients of a living donor, the rate of all-cause graft failure was not statistically higher for recipients of a standard criteria deceased donor (hazard ratio, 1.1; 95% confidence interval [CI], 0.8-1.6). Recipients of a standard criteria deceased donor, compared with recipients of a living donor had a higher rate of delayed graft function (23.6% versus 18.7%; odds ratio, 1.3; 95% CI, 1.0-1.6) and a longer length of stay for the kidney transplant surgery (mean difference, 1.7 d; 95% CI, 0.5-3.0). CONCLUSIONS: After accounting for many important donor and recipient factors, we failed to observe a large difference in the risk of all-cause graft failure for recipients of a standard criteria deceased versus living donor. Some estimates were imprecise, which meant we could not rule out the presence of smaller clinically important effects.

Características de los pacientes trasplantados renales con retraso de la función del injerto, asistidos en el servicio de terapia intensiva del Instituto de Cardiología de Corrientes entre 2016 y 2018 / Characteristics of renal transplant patients with delayed graft function, assisted in the intensive therapy service of the Institute of current Cardiology between 2016 and 2018

Esta investigación tuvo por objetivo describir las características de los pacientes trasplantados renales con retraso en la función del injerto. Estudio descriptivo, transversal y observacional. Población: trasplantados renales asistidos en el Instituto de Cardiología de Corrientes entre 2016 y 2018 que cumplieron los criterios de inclusión. Se utilizó formulario de elaboración propia; los datos se obtuvieron de revisión de historias clínicas. La información recolectada se analizó mediante programa informático Epidat_4.2. Se contó con el aval del comité de la institución. Se estudiaron 61 pacientes trasplantados; 43% pertenecía a donantes vivos y 57% a cadavéricos. El 66% de donantes cadavéricos tuvo retraso de la función del injerto, los de donantes vivos no lo presentaron. En cuanto al sexo 48% de los varones presentaron retraso en la función; en las mujeres fue el 28%. En edad de los pacientes, la media fue de 40,6 años ± 15,7; se observó mayor frecuencia de retrasos de la función en el grupo etario de 31 a 50 años con 44%. En cuanto al estado nutricional 17% que se encontraba con sobrepeso y 48% con bajo peso presentaron retraso de la función del injerto. Según los años en diálisis pre trasplante el 65% de aquellos con 4 a 7 años de diálisis presentaron retraso en la función del injerto. Según tiempo de isquemia fría del órgano trasplantado, 52% presentó retraso en la función del injerto cuando el tiempo fue mayor a 15 horas. En requerimiento de diálisis pos-operatorio, el 66% presentó retraso en la función del injerto y pertenecían a donantes cadavéricos. En índice de resistencia vascular renal en las primeras 24hs, el 65% con retraso de la función del injerto presentó índice patológico. En conclusión, sexo masculino, grupo etario de 31 a 50 años, tener alterado el estado nutricional, haberse dializado pre trasplante entre 4 a 7 años, padecer un tiempo prolongado de isquemia fría > 15 horas y presentar un índice de resistencia vascular renal patológico, son características presentes; en trasplantados renales con retraso en la función del injerto; y requieren ser tenidos en cuenta cuando se planean estas cirugías[AU]

Effect of Perioperative Optimization of Arterial Oxygen Content and Perfusion Pressure on the Function of the Transplanted Kidney in the Retrospective Study of Excretory Function and Assessment of New Markers of Kidney Damage: IL-18, Neutrophil Gelatinase-Associated Lipocalin, and Clusterin.

INTRODUCTION: The concept of anesthesia, in which kidney perfusion is optimized, the use of nephrotoxic drugs is avoided, and general anesthesia with protective and preconditioning properties of the graft is applied, is a key element of the therapeutic strategy in kidney transplantation (KTx). MATERIAL AND METHOD: A total of 86 patients (mean age: 49.4 ± 14.0 years, 66% men) with end-stage renal disease who underwent KTx between 2012 and 2015 were included in this retrospective study. Our aim was to assess the effect of oxygen content in arterial blood and selected hemodynamic parameters on the graft function and the occurrence of delayed graft failure. RESULTS: No differences were found in baseline characteristics, indication for transplantation, and surgical technique used among study population. No correlation was found between oxygen delivery exponents and both standard markers of renal function and new biochemical markers (eg, IL-18, clusterin, and neutrophil gelatinase-associated lipocalin [NGAL]). DISCUSSION: In our study, hemodynamic parameters measured at scheduled intervals did not exceed the physiological range, which might have been the reason for the lack of correlation between the function of graft and the described hemodynamic conditions. At the same time, in the observed ranges of perfusion pressure during optimization of the oxygen content, no correlations were found with the postoperative function of the transplanted kidney. That observation could be a valuable conclusion for reducing the tendency of maintaining high blood pressure with the abuse of catecholamines, especially vasoconstrictors, and volume therapy, whose negative effect on tissue perfusion is unequivocal.

Predictive Value of Intraoperative Doppler Flowmetry for Delayed Graft Function in Kidney Transplantation: A Pilot Study.

BACKGROUND: The delayed graft function (DGF) in kidney transplantation (KT) is a risk factor for long-term poor graft survival. The pathogenesis is multifactorial but mainly related to an ischemia-reperfusion injury. However, the graft hemodynamics have been recently identified as a key aspect for early DGF risk assessment and potential therapeutic intervention. METHODS: A pilot study on 20 single kidney grafts from donor after brain death with intraoperative measurement of graft arterial flowmetry, 30 minutes after reperfusion. Exclusion criteria were grafts with multiple arteries or severe atherosclerosis of the recipient's external iliac artery. RESULTS: KT recipients with DGF (n = 4, 20%) were homogenous with controls (n = 16) in terms of cold ischemia time, donor age, recipients' hemodynamic parameters, renal artery, and recipients' external iliac artery diameters. Nonetheless, at transplant, the kidney grafts that developed DGF were characterized by a significantly higher renal artery resistive index (DGF vs no-DGF 0.96 ± 0.04 vs 0.77 ± 0.13, P = .02), as well as lower flow extraction rate (24.8% ± 11.8 vs 59.2% ± 21.1, P < .01). CONCLUSIONS: Intraoperative arterial graft flowmetry seems to be an effective tool to identify grafts at high risk of DGF.

Utilization of Donor Kidneys With Acute Kidney Injury in Pediatric Kidney Transplant Recipients.

BACKGROUND: An elevated terminal creatinine is frequently used as a reason for organ refusal in pediatric kidney transplantation. There is increasing evidence that adults who receive kidneys from donors with moderate to severe acute kidney injury (AKI) have similar outcomes to recipients who receive kidneys from donors with none to mild AKI. METHODS: We used the Scientific Registry of Transplant Recipients to determine how many pediatric kidney transplant recipients developed delayed graft function (DGF) between 2000 and 2010. RESULTS: When stratified by the donor terminal creatinine, there was no significant difference in the recipient discharge creatinine or the likelihood of developing DGF. In a logistic regression model, older donor age, male donors, and a longer cold ischemia time but not donor terminal creatinine were independent predictors of DGF. There were very few graft loss events documented in this study. CONCLUSIONS: Our results are in agreement with previously published data; a high donor terminal creatinine is not significantly associated with DGF in pediatric renal transplant recipients. Additional studies investigating the risk of rejection and long-term graft function are needed before adopting the practice of accepting kidneys with moderate to severe AKI in pediatric kidney transplant recipients.

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.

Kidney allograft dysfunction due to ipsilateral thigh arteriovenous graft.

Arteriovenous graft in the thigh is used not infrequently for hemodialysis. Outcomes with this lower extremity dialysis access are generally comparable to upper extremity access and superior to long-term catheter use. However, it could have significant implications in a patient getting a kidney transplant. Here we describe a case of thigh arteriovenous graft causing kidney allograft dysfunction in a new transplant recipient, and this resolved with graft ligation.

Tubular Ectasia in Renal Allograft Biopsy: Associations With Occult Obstructive Urological Complications.

BACKGROUND: Urological obstructive complications (UOC) affect up to 15% of kidney transplants (KTX). Most cases are excluded by ultrasonography (US); however, accuracy may be limited in the early transplant phase. Features of acute tubular injury (ATI) in KTX biopsy may be informative but histological features indicating UOC are ill defined. Tubular ectasia (TE) was shown to be associated with UOC in experimental data. We evaluated the association of histomorphological features, particularly TE, with occult (=without relevant hydronephrosis in US) UOC and renal outcomes. METHODS: We included all recipients with an early indication biopsy (976 of 1537 consecutive KTX). The biopsy finding of TE classified as "suspicious of UOC" was compared with the following endpoints: delayed graft function, estimated glomerular filtration rate, and occult UOC. Additionally, histopathological features of ATI were reevaluated by a single pathologist to increase diagnostic accuracy. RESULTS: Fifty-eight (5.9%) patients presented with TE, which was not related to delayed graft function or estimated glomerular filtration rate. Forty percent of patients had a UOC (most frequently ureteral stenosis) close to biopsy. Comparing these biopsies to matched controls, TE was significantly associated with UOC (odds ratio 2.69; P = 0.018). After histopathological reevaluation of these biopsies including additional features of ATI, we developed a final multivariate model with a highly significant relationship to UOC (Receiver operating characteristic-area under the curve: 0.77; P = 0.001). The model provides a specificity of 78% and negative predictive value of 73%. CONCLUSIONS: TE together with additional signs of ATI indicates occult UOC. This histological phenotype should trigger more detailed evaluation for UOC when there is no evidence of relevant hydronephrosis in the ultrasonography.

Delayed Graft Function in Simultaneous Liver Kidney Transplantation.

BACKGROUND: Delayed graft function (DGF) is associated with inferior posttransplant outcomes in kidney transplantation. Given these adverse outcomes, we sought to determine the incidence, unique risk factors, and posttransplant outcomes for simultaneous liver kidney (SLK) transplant recipients developing DGF. METHODS: We studied 6214 adult SLK recipients from March 2002 to February 2017 using the Scientific Registry of Transplant Recipients. We determined associations between risk factors and DGF using Poisson multivariate regression and between DGF and graft failure and mortality using Cox proportional hazard analysis. RESULTS: The overall rate of DGF was 21.8%. Risk factors for DGF in the hepatitis C virus (HCV)-negative recipient population included pretransplant dialysis (adjusted incident rate ratio [aIRR] 3.26, P = 0.004), donor body mass index (aIRR 1.25 per 5 kg/m, P = 0.01), and transplantation with a donation after circulatory death (aIRR 5.38, P = 0.001) or imported donor organ (regional share aIRR 1.69, P = 0.03; national share aIRR 4.82, P < 0.001). DGF was associated with a 2.6-fold increase in kidney graft failure (adjusted hazard ratio [aHR] 2.63, P < 0.001), 1.6-fold increase in liver graft failure (aHR 1.62, P < 0.001), and 1.6-fold increase in mortality (aHR 1.62, P < 0.001). CONCLUSIONS: In HCV-negative SLK recipients, recipient pretransplant dialysis and components of kidney graft quality comprise significant risk factors for DGF. Regardless of HCV status, DGF is associated with inferior posttransplant outcomes. Understanding these risk factors during clinical decision-making may improve prevention of DGF and may represent an opportunity to improve posttransplant outcomes.

Cold Pulsatile Machine Perfusion Versus Static Cold Storage for Kidneys Donated After Circulatory Death: A Multicenter Randomized Controlled Trial.

BACKGROUND: The benefits of cold pulsatile machine perfusion (MP) for the storage and transportation of kidneys donated after circulatory death are disputed. We conducted a UK-based multicenter, randomized controlled trial to compare outcomes of kidneys stored with MP versus static cold storage (CS). METHODS: Fifty-one pairs of kidneys donated after circulatory death were randomly allocated to receive static CS or cold pulsatile MP. The primary endpoint, delayed graft function, was analyzed by "intention-to-treat" evaluation. RESULTS: There was no difference in the incidence of delayed graft function between CS and MP (32/51 (62.8%) and 30/51 (58.8%) P = 0.69, respectively), although the trial stopped early due to difficulty with recruitment. There was no difference in the incidence of acute rejection, or in graft or patient survival between the CS and MP groups. Median estimated glomerular filtration rate at 3 months following transplantation was significantly lower in the CS group compared with MP (CS 34 mL/min IQR 26-44 vs MP 45 mL/min IQR 36-60, P = 0.006), although there was no significant difference in estimated glomerular filtration rate between CS and MP at 12 months posttransplant. CONCLUSIONS: This study is underpowered, which limits definitive conclusions about the use of MP, as an alternative to static CS. It did not demonstrate that the use of MP reduces the incidence of delayed graft function in donation after circulatory death kidney transplantation.