Time Of Kidney Transplantation Research Articles

Renal transplantation in older adults: retrospective cohort study to examine the impact of the new 2019 kidney offering scheme on older adult transplant recipients.

In 2019, a new kidney offering scheme was launched in the United Kingdom, aiming to better match estimated patient survival and graft life expectancy. The scheme's impact on older patients undergoing kidney transplantation (KT) is unknown. This study aims to compare the outcomes of older adult KT recipients before and after introduction of the 2019 scheme. A retrospective observational cohort study of older adults who underwent KT was undertaken. Group 1 were transplanted between 1 September 2017 and 31 August 2019 (2006 allocation scheme) and group 2 between 1 September 2019 and 31 August 2021 (2019 offering scheme). An older adult was any person ≥60 years old at the time of KT. Univariable binary logistic regression analysis was performed to determine odds ratios (OR) and 95% confidence intervals (CI). There were 107 older adult deceased donor KT recipients, 62 from group 1 and 45 from group 2. Median age at transplantation was 68 (interquartile range [IQR] 62-71) and 67 (IQR 64-73) years, respectively. Univariable analysis showed that re-intervention (OR 6.486, 95% CI 1.306-32.216, p = 0.022) and critical care admission (OR 5.619, 95% CI 1.448-21.812, p = 0.013) were significantly more likely in group 2. Group 2 recipients were significantly more likely to have a level 4 human leucocyte antigen (HLA) mismatch (OR 4.667, 95% CI 1.640-13.275, p = 0.004) and to have undergone previous KT (OR 4.691, 95% CI 1.385-15.893, p = 0.013). The introduction of the 2019 offering scheme was associated with re-intervention and critical care admission for older KT recipients. We also observed less-favourable HLA matches but more KT in difficult-to-match groups.

Bone Phenotype and Fracture Risk in Patients with Type 2 Diabetes at the Time of Kidney Transplantation

Bone Phenotype and Fracture Risk in Patients with Type 2 Diabetes at the Time of Kidney Transplantation

Gender differences in cardiovascular outcomes of kidney transplant recipients: A retrospective cohort study.

The purpose of this study was to investigate gender differences in cardiovascular outcomes of kidney transplant recipients (KTRs). Here, a retrospective cohort study was conducted, and data from the National Health Insurance Research Database in Taiwan were used. In total, 2904 patients who had end-stage renal disease (ERSD) and received kidney transplantation (KT) were identified by propensity score matching (PSM) and were enrolled from 1997 to 2012, with follow-up ending in 2013. Besides, major adverse cardiovascular events (MACEs) were defined as a composite of all-cause mortality, nonfatal myocardial infarction, and nonfatal strokes. Apart from that, hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated by Cox regression, while the Bayesian network model was constructed to assess the importance of risk factors for MACEs. Furthermore, the original cohort was a sensitivity analysis. Women had a lower risk of MACEs compared with men (hazard ratio [HR]: 0.84; 95% CI: 0.72-0.98; P = .024). Beyond that, stratified analysis of age and waiting time for KT showed that the risk of MACEs was significantly lower in women than in men among KTRs aged > 50 years (HR: 0.79; 95% CI: 0.62-1.0; P = .05) or waiting time for KT ≤ 6 years (HR: 0.85; 95% CI: 0.72-0.99; P = .04). Bayesian network indicated that age is an important determinant of cardiovascular outcomes in KTRs, regardless of gender. In Taiwan, women had a lower risk of adverse cardiovascular outcomes than men in KTRs aged > 50 years or with a waiting time for KT ≤ 6 years. Furthermore, age is an important independent determinant for the prognosis of KTRs.

#715 Adiponectin / leptin ratio as an index to determine the risk of metabolic and rejection complications in patients after kidney transplantation

Abstract Background and Aims Adipose tissue, as an endocrine and paracrine organ, produces several hormones that are involved in the regulation of metabolic and inflammatory processes or immune system activity. While leptin is the main pro-inflammatory marker of adipose tissue, adiponectin is characterized by its anti-inflammatory effects. The adiponectin / leptin (A/L) ratio had been shown to correlate better with the occurrence of cardiometabolic risk factors than hormone concentrations alone. Results in the general population suggest that an A/L ratio > 1 can be considered normal, an A/L ratio of 0.5-1 indicates a moderate increase, and an A/L ration < 0.5 a high increase in cardiometabolic risk. The first aim of our study was to determine the risk of developing post-transplant diabetes mellitus (PTDM), prediabetes and other metabolic risk factors in relation to the A/L ratio in patients after kidney transplantation (KT). The second aim was to determine the risk of developing acute graft rejection in relation to the A/L ratio in patients after KT. Method A total of 104 patients were included in our prospective analysis after applying inclusion and exclusion criteria. Pre-transplantation and subsequently at 3, 6 and 12 months after KT, we recorded baseline characteristics of donors and recipients, including parameters characterizing graft function, metabolic (lipid profile, indices of glucose metabolism) and anthropometric parameters. At the same time, we examined serum adipocytokine concentrations (adiponectin, leptin) and calculated the A/L ratio. In the third month after KT, all patients underwent protocol graft biopsy and donor specific antibody (DSA) testing by Luminex method. Results We found that during the follow-up period, there was a significant increase in the A/L ratio in the control group (p = 0.0013) and, on the other hand, a significant decrease in the group who developed PTDM (p = 0.0003). Comparing the different subgroups divided on the A/L ratio one year after KT, we found that patients with an A/L < 0.5 were significantly longer in the dialysis program, had higher body mass index (BMI), waist circumference, worse graft function, and a higher prevalence of prediabetes and PTDM compared with those whose A/L ratio was > 1. Using logistic regression in multivariate analysis, we identified age at the time of KT [OR 1.0709, (p = 0.0337)], triglycerides level at 1 year after KT [OR 2.7735, (p = 0.446)] and A/L ratio < 0.5 [OR 3.1724, (p = 0.014)] as independent risk factors for the development of prediabetes and PTDM 1 year after KT. At the same time, after adjusting for differences in baseline donor and recipient characteristics, we identified the subgroup with an A/L ratio < 0.5 pre-transplant [HR 1.6126, (p = 0.0133)] and 3 months after KT [HR 1.3150, (p = 0.0172)] as an independent risk factor for the development of acute graft rejection. In the subsequent specification of the rejection episode, we found that A/L ratio < 0.5 pre-transplant [HR 2.2353, (p = 0.0357)] and 3 months after KT [HR 3.0954, (p = 0.0237)] is and independent risk factor for the occurrence of acute humoral rejection with DSA positivity. Conclusion In our study, we found that an A/L ratio < 0.5 is an independent risk factor for the development of prediabetes, PTDM 1 year after KT and acute humoral graft rejection with de novo DSA production in the third month after KT. This is the first study to investigate the correlation of the A/L ratio with the risk of developing metabolic and immunological complications in patients after KT.

#2040 Effect of donor–recipient size mismatch on long-term graft survival in pediatric kidney transplantation: a multicenter cohort study

Abstract Background and Aims Kidney transplantation (KT) is the main treatment option for patients with end-stage kidney disease (ESKD). However, it is limited by the low number of donor organs. Moreover, donor–recipient size mismatching is a common problem in KT given the various types of donors. Donor–recipient size mismatching is commonly occurs in pediatric kidney transplantation (KT). However, its effect on graft survival remains unknown. This study aimed to determine the effect of donor–recipient size mismatch on the long-term survival rate of transplant kidneys in pediatric KT. Method A total of 241 pediatric patients who received KT were enrolled. The medical records of all patients were retrospectively reviewed, and the correlation between donor–recipient size mismatch and graft function and long-term graft outcome was analyzed according to donor–recipient size mismatch. Results Recipients and donors’ mean body weight at the time of KT were 34.31 ± 16.85 and 56.53 ± 16.73 kg, respectively. The mean follow-up duration was 96.49 ± 52.98 months. The mean age of donors was 34.74 ± 14.91 years, and the ratio of males and females was 105:136. Approximately 81.7%, 1.2%, and 17.0% of all transplant donors were identified as living-related, living-unrelated, and deceased donors, respectively. A significant positive correlation was observed between donor–recipient body weight ratio (DRBWR) or donor–recipient body surface area ratio (DRBSR) and graft function until 1 year after KT. However, this correlation could not be confirmed at the last follow-up. The results of long-term survival analysis using Fine and Gray's subdistribution hazard model showed no significant difference of the survival rate of the transplant kidney according to DRBWR or DRBSR. Conclusion Donor–recipient size mismatch in pediatric KT is not an important factor in determining the long-term prognosis of transplant kidneys.

#1245 Standard or personalized policy of peritoneal catheter removal at kidney transplantation?

Abstract Background and Aims The presence of peritoneal dialysis (PD) catheter in an immunosuppressed kidney transplant recipient can increment the risk of infectious complications after transplant. For this reason, it is thought that management of PD catheters at the time of transplant can have an impact on patient and graft outcomes. However, there is no agreement when to remove peritoneal dialysis catheter after transplantation. According to European Guidelines, the catheter can be left in situ for 3-4 months despite a functional graft. Our aim was to review the data from our center regarding infectious PD associated complications after kidney transplant. Method We retrospectively reviewed all 132 patients that were previously on PD and were admitted to our center for renal transplantation between January of 2013 and June of 2023, and had information regarding timing of removal of PD access. Simple descriptive and inferential statistics were used to generate results. Categorical data were described using frequency and percentage. Our main outcome was to assess the PD infectious catheter-associated complications. Our secondary outcomes were the timing of removal of PD catheter after renal transplantation, number of episodes of dialysis post transplantation, and kidney replacement therapy (KRT) used. Our follow up included the time from kidney transplantation (KT) until they removed PD catheter. Those who removed PD catheter at the timing of renal transplantation were excluded when evaluating the infectious complications. Results From the 132 kidney transplant recipients eight patients removed PD catheter at the time of the transplant due to ongoing PD associated infection. Sixty-nine patients were men (52.3%), with a median (IQR) age at transplantation of 48.4 years (41-57). Regarding donors’ characteristics, 88 (33.3%) were deceased, 21 of which were expanded criteria donors, and 44 (66.7%) were living donors. A total of 19 (14.4%) patients had history of PD infectious complications in the three months before transplantation. From the 124 patients that remained with the PD catheter after KT the adverse event infection occurred in 19 (15.3%) patients and two of these had previous access related infection in the 3 months interval before transplantation. The adverse events were: exit-site infection (ESI) 10.4% (n = 19), peritonitis 3% (n = 4) and tunnel infection 1.6% (n = 2). Half required hospitalization mainly due to center logistics for catheter removal. No deaths were registered. The identified microorganisms are present in Table 1. The median (IQR) time of removal of the PD catheter was 4 (3-5) months. Sixteen patients (12.9%) required KRT due to delayed graft function: ten patients used the Tenckhoff catheter and the rest performed haemodialysis (four using central venous catheter and two using arteriovenous fistula). Three patients remained dialysis dependent. When analysing the living donor group the rate of KRT was even lower, with three (6.8%) patients requiring dialysis, and only one used the PD catheter. Conclusion Despite the timing of PD catheter removal was according to the European Guidelines, the risk of PD catheter associated infections is not negligible (15.3%), not to mention the burden for the patient to keep an abdominal device demanding routinely care of the exit site. Peritonitis rate was low and comparable to previous studies. Considering the utility of remaining with the catheter, the risk of needing KRT, namely in living donor KT, was low. We postulate whether PD catheter removal at the time of KT should be considered, especially when the risk of late graft function is low, as in living donors, and/or the risk of PD catheter related infections is high. For this reason, we call for an individualized policy regarding catheter removal in the transition to KT.

#1888 Association between intrapatient variability of serum tacrolimus levels with the development of diabetes in post-kidney transplantation patients

Abstract Background and Aims Kidney transplantation is the most cost-effective renal replacement therapy compared to dialysis. Diabetes is main cause of increased cardiovascular risk and death. Post-transplant Diabetes Mellitus (PTDM) it refers to presence of diabetes in an environment after kidney transplantation; According to the ADA (American Diabetes Association) criteria, the diagnosis must be made with a tolerance test with 75 grams of oral glucose (Oral glucose tolerance test-OGTT) or the determination of glycosylated hemoglobin 1Ac (Hb1Ac) in a post-transplant period of stability of the immunosuppression dose and without infections. There are various risk factors for the development of PTDM: hypomagnesemia, glucocorticoids, calcineurin inhibitors (tacrolimus and cyclosporine); hepatitis C virus and cytomegalovirus infections. In a Mexican kidney transplant recipients in Guadalajara, Andrade SG demonstrated that the incidence of PTDM was 10.1% at 1 year post-transplant. In the Spanish population, Porrini E demonstrated that tacrolimus represents a risk factor for the development of PTDM, increasing the incidence of prediabetes by 33% at 12 months post-transplant. Several mechanisms have been implicated in the association of calcineurin inhibitor and PTDM: decreased insulin secretion, glucose intolerance, reduced pancreatic beta cell mass, increased islet apoptosis and decreased insulin gene expression. Studies mention that tacrolimus (FK) is more diabetogenic than cyclosporine (CsA) especially at levels above 20 ng/mL. The DIRECT study (Diabetes Incidence after Renal Transplantation) showed the incidence in 73 kidney transplant patients with CsA (26%) and 96 FK patients (33.6%, p = 0.046). By the other side, Malik RF mentions that FK levels aren´t a risk factor for the development of PTDM. To demonstrate that the high intrapatient variability of tacrolimus/cyclosporine serum levels correlates with the development of diabetes (PTDM) in kidney transplant recipients at the central military hospital in Mexico City. Method Observational, analytical, longitudinal and retrospective study. All kidney transplant recipients from living donors and cadaveric donors from January 2002 to December 2020 were included. FK and CsA were used as maintenance immunosuppression. Serum levels of FK/CsA, Hb1Ac and glucose were measured at months 0, 3, 6, 9 and 12 and intra-patient variability (IPV) of FK/CsA levels was calculated for each patient. The patients were separated into 2 groups, IPV low and IPV high according to the mean the coefficient of variability (CV). The IPV of the calcineurin inhibitor was estimated by calculating the CV in each patient according to the following equation: CV(%)= (SD/mean trough concentration of FK/ CsA)×100. The diagnosis of PTDM followed the criteria of the American Diabetes Association. The Mann Whitney U test was used. Results 638 kidney transplant recipients were included. The mean age of the recipients was 36.78 (±12.81) years. At the time of kidney transplant, the BMI was 22.67 (±3.90) and 25.76 (±3.99) kg/m² BS at 1 year post-transplant for whole cohort. At 1 year post-transplant, 72.3% patients were on FK and 27.7% on CsA. Hb1Ac for whole cohort was 4.81 (±0.71)% and 4.84 (±0.77)% at month 0 and 12 post-kidney transplant, respectively. FK and CsA levels were 12.41 (±5.31) and 234.34 (±87.80) ng/mL and 9.13 (±5.3) and 194.38 (±92.44) ng/mL in the PTDM and non-PTDM groups, respectively (p = 0.029). 17.96% of patients developed PTDM. Mean CV of the entire cohort was 33.84 (±20.41)%. When performing the analysis of the IPV coefficient by subgroups of maintenance immunosuppression used at 1 year post-transplant: the IPV of FK was 43.39 (±18.49)% and 29.99 (±17.56)% in the PTDM and non-PTDM groups respectively, p = 0.000, which shows that patients with a high IPV coefficient of tacrolimus developed more PTDM than those with low variability, student's t-test to compare IPV was 0.03. The IPV of CsA was 38.61 (±18.76)% and 37.51 (±25.67)% in the PTDM and non-PTDM groups respectively, p = 0.819. Conclusion High intrapatient variability of tacrolimus was correlated with the development of PTDM in Mexican kidney transplant recipients.

Left Ventricular Hypertrophy After Renal Transplantation: Systematic Review and Meta-analysis.

Left ventricular hypertrophy (LVH) in patients with end stage renal disease undergoing renal replacement is linked to an increased risk for cardiovascular diseases. Dialysis does not completely prevent or correct this abnormality, and the evidence for kidney transplantation (KT) varies. This analysis aims to explore the relationship between KT and LVH. MEDLINE and Scopus were systematically searched in October 2023. All cross-sectional and longitudinal studies that fulfilled our inclusion criteria were included. Outcome was left ventricular mass index (LVMI) changes. We conducted a meta-analysis using a random effects model. Meta-regression was applied to examine the LVMI changes dependent on various covariates. Sensitivity analysis was used to handle outlying or influential studies and address publication bias. From 7416 records, 46 studies met the inclusion criteria with 4122 included participants in total. Longitudinal studies demonstrated an improvement of LVMI after KT -0.44 g/m2 (-0.60 to -0.28). Blood pressure was identified as a predictor of LVMI change. A younger age at the time of KT and well-controlled anemia were also associated with regression of LVH. In studies longitudinally comparing patients on dialysis and renal transplant recipients, no difference was detected -0.09 g/m2 (-0.33 to 0.16). Meta-regression using changes of systolic blood pressure as a covariate showed an association between higher blood pressure and an increase in LVMI, regardless of the modality of renal replacement treatment. In conclusion, our results indicated a potential cardiovascular benefit, defined as the regression of LVH, after KT. This benefit was primarily attributed to improved blood pressure control rather than the transplantation itself.

Cetuximab for the treatment of cutaneous squamous-cell carcinoma in kidney transplant recipients – A retrospective cohort study

Background: Kidney transplant recipients are at high risk of developing cutaneous squamous cell carcinoma (cSCC) due to prolonged immunosuppression. While most lesions can be managed with local therapy, a subset of patients develop advanced cSCC that is unresectable, recurrent or metastatic. Immune check point inhibitors (ICI) and chemotherapy may jeopardize the transplanted kidney. Cetuximab, an anti-epidermal growth factor receptor antibody, has demonstrated efficacy in advanced cSCC, but data regarding efficacy and safety in solid organ transplant recipients is lacking. Methods: This retrospective cohort study analyzed kidney transplant recipients diagnosed with locally advanced or metastatic cSCC who were treated with cetuximab. Results: Seventeen patients were included in the analysis. The median age was 57 years at the time of kidney transplantation and 62 years at diagnosis of index lesion. Cetuximab was administered with radiation therapy as a radiosensitizer in 58.8% of patients, as monotherapy in 17.6% of patients, and with chemotherapy in 23.5% of patients. Importantly, no detrimental impacts on kidney graft function were observed. The main toxicites were grade 1–2 skin reactions and electrolyte imbalance. Of the 10 patients receiving cetuximab with chemoradiotherapy as a radiosesnitizer, 2 were treated with definitive intent, 7 of them in the adjuvantsetting, and 1 for palliative pourpose. Over half of these patients achieved a complete response (37.29%) or no recurrence after resection (23.5%). Median time to disease progression was 10 months. Conclusions: This novel study suggests cetuximab has a reasonable safety profile and potential efficacy in kidney transplant recipients with advanced cSCC, without impairing allograft function. Further prospective research with larger sample sizes is warranted to confirm these findings. Cetuximab should be investigated as a systemic treatment option for this high-risk population of solid organ transplant recipientss with recurrent, metastatic, or unresectable cSCC.

Arteriovenous fistula for haemodialysis as a predictor of de novo heart failure in kidney transplant recipients.

The haemodynamic effects of a functioning haemodialysis arteriovenous fistula (AVF) can cause or exacerbate heart failure (HF). We investigated whether the presence of an AVF at the time of kidney transplant (KT) is associated with de novo HF. This was an observational cohort study including adult patients who received a KT in the West of Scotland between 2010 and 2020. We evaluated the risk and associations of pretransplant factors with de novo HF, alone and as a composite cardiovascular (CV) outcome (including non-fatal myocardial infarction, non-fatal stroke, de novo HF and CV death). Multivariable proportional hazards regression and sensitivity analyses were used to identify independent correlates of the outcomes. Among 1330 included patients, the incident rate of de novo HF after transplantation was 58/1000 person-years [95% confidence interval (CI) 50-67] in AVF patients (n=716) compared with 33/1000 person-years (95% CI 27-41) in non-AVF patients (n=614). De novo HF was associated with the presence of an AVF [adjusted hazard ratio (aHR) 2.14 (95% CI 1.40-3.26)], duration of dialysis [aHR 1.03/year increase (95% CI 1.01-1.04)], age at transplant [aHR 1.03/year increase (95% CI 1.02-1.05)], female sex [aHR 1.93 (95% CI 1.40-2.65)] and pretransplant diabetes [aHR 2.43 (95% CI 1.48-4.01)]. The presence of an AVF was also associated with the composite CV outcome [aHR 1.91 (95% CI 1.31-2.78)]. The presence of an AVF may be an underrecognized modifiable predictor of de novo HF posttransplantation.

Etelcalcetide use During Maintenance Hemodialysis and Incidence of Parathyroidectomy After Kidney Transplantation

Etelcalcetide is an i.v. calcimimetic agent, effectively reducing parathyroid hormone levels in patients on maintenance hemodialysis (HD). The clinical impact of discontinuing etelcalcetide at the time of kidney transplantation is unknown. We retrospectively reviewed all patients on HD meeting predefined criteria who received a kidney transplant at our institution between January 1, 2015, and December 12, 2022. The incidence of parathyroidectomy and the evolution of calcium, phosphate, and intact parathyroid hormone (iPTH) levels after transplantation was analyzed according to the type of calcimimetic treatment before transplantation (cinacalcet vs. etelcalcetide vs. none). Overall, 372 patients (aged 53 years; interquartile range [IQR]: 42-62 years) were included. At the time of transplantation, 35, 75, and 262 patients were under etelcalcetide, cinacalcet, or no calcimimetic, respectively. After 1064 (IQR: 367-1658) days, the incidences of parathyroidectomy in the etelcalcetide, cinacalcet, no calcimimetic groups were 29%, 12%, and 1%, respectively (P< 0.001). Etelcalcetide was associated with an increased incidence of parathyroidectomy after adjustment for age, sex, and HD vintage (hazard ratio [HR]: 97.0, 95% confidence interval [CI]: 19.1-493.9, P< 0.001). The incidence of parathyroidectomy was related to etelcalcetide dosage (6/11 [54.6%] in patients with≥ 10 mg vs. 4/24 [16.7%] in patients with< 10 mg, P= 0.02). Moreover, peak calcium levels were higher (P< 0.001) and parathyroidectomy was performed earlier (median 80 vs. 480 days, P< 0.001) in the etelcalcetide compared with the cinacalcet group. Long-term graft function, graft loss, and mortality were similar. Etelcalcetide use during maintenance HD is associated with an increased incidence of early parathyroidectomy after transplantation compared to cinacalcet or no calcimimetic.

Transplant Candidates of 70+ Years Have Superior Survival If Receiving Pre-Emptively a Living Donor Kidney.

Background: The number of kidney transplant recipients over 70 years of age is increasing but detailed data on patient and graft survival in the modern era of immune suppression are few. Methods: A single-center cohort of patients of 70 years and older (n = 349) at time of kidney transplantation from 2010-2020 were followed until January 2023. Results: The median age was 73 years with a median follow-up of 4.3 years. Fifty percent of recipients of a living donor kidney (LDK, n = 143) received their graft pre-emptively. Cumulative death-censored graft survival was excellent in the LDK group and reached 98% at 5 years vs. 85% in the deceased donor kidney (DDK) group. Primary non-function (38%) and rejection (43%) were the major causes of graft loss in the first year after DDK transplantation. Rejection-related graft loss was 4.6% during follow-up. Median recipient survival was superior in the subgroup of pre-emptively transplanted LDK patients compared to non-pre-emptively LDK transplanted patients (11.1 versus 6.2 years). Non-pre-emptively transplanted patients had a significantly increased incidence of infection (HR 3.81, 1.46-9.96) and cardiovascular-related causes of death (HR 3.35, 1.16-9.71). Pre-emptive transplantation was also associated with a significantly improved graft survival in the DDK recipients but this result was confounded by significantly better HLA matching and younger donor age in this group. Conclusions: Pre-emptive LDK transplantation in patients of 70 years or older confers superior graft and recipient survival.

Frailty in the context of kidney transplantation.

Frailty, defined as an inappropriate response to stressful situations due to the loss of physiological reserve, was initially described in the elderly population, but is currently being identified in younger populations with chronic diseases, such as chronic kidney disease. It is estimated that about 20% of patients are frail at the time of kidney transplantation (KT), and there is great interest in its potential predictive value for unfavorable outcomes. A significant body of evidence has been generated; however, several areas still remain to be further explored. The pathogenesis is poorly understood and limited to the extrapolation of findings from other populations. Most studies are observational, involving patients on the waiting list or post-KT, and there is a scarcity of data on long-term evolution and possible interventions. We reviewed studies, including those with Brazilian populations, assessing frailty in the pre- and post-KT phases, exploring pathophysiology, associated factors, diagnostic challenges, and associated outcomes, in an attempt to provide a basis for future interventions.

Changes in graft outcomes in recipients

Kidney transplant (KT) was initially associated with poor outcomes, especially in smaller recipients. However, pediatric transplantation has evolved considerably over time. We investigated the impact of weight at the time of transplant and whether outcomes changed over 25 years for <10 kg recipients. Using the UNOS database, pediatric recipient outcomes were analyzed between 1/1/99 and 12/31/14. KT weight was stratified: <8.6 kg (mean weight of recipients <10 kg), 8.6-9.9 kg, 10-14.9 kg, 15-29.9 kg, and ≥30 kg. Outcomes in recipients <10 kg were then compared between 1990-1999 and 2000-2014. 17 314 pediatric KT recipients were included; 518 (3%) had a transplant weight <10 kg. The highest rates of allograft loss and death were in recipients <8.6 kg and ≥30 kg. Recipients <8.6 kg also had higher rates of delayed graft function, rejection, and longer hospital length of stay. In the multivariable Cox regression model, transplant weight was not a predictor of allograft loss. When compared with recipients <8.6 kg, patient survival hazard ratios associated with recipient weight of 10-14.9 kg, 15-29.9 kg, and ≥30 kg were 0.61 (95%CI: 0.4, 1), 0.42 (95%CI: 0.3, 0.7) and 0.32 (95%CI: 0.2, 0.6), respectively. In the later era of transplant, recipients <10 kg had improved outcomes on univariate analysis; however, the era of transplantation was not an independent predictor of allograft loss or patient survival in Cox regression models. Outcomes in children weighing 8.6-9.9 kg at the time of KT were similar to higher weight groups and improved over time; however, special precautions should be taken for recipients <8.6 kg at the time of transplant.

Re-assessing prolonged cold ischemia time in kidney transplantation through machine learning consensus clustering.

We aimed to cluster deceased donor kidney transplant recipients with prolonged cold ischemia time (CIT) using an unsupervised machine learning approach. We performed consensus cluster analysis on 11615 deceased donor kidney transplant patients with CIT exceeding 24h using OPTN/UNOS data from 2015 to 2019. Cluster characteristics of clinical significance were identified, and post-transplant outcomes were compared. Consensus cluster analysis identified two clinically distinct clusters. Cluster 1 was characterized by young, non-diabetic patients who received kidney transplants from young, non-hypertensive, non-ECD deceased donors with lower KDPI scores. In contrast, the patients in cluster 2 were older and more likely to have diabetes. Cluster 2 recipients were more likely to receive transplants from older donors with a higher KDPI. There was lower use of machine perfusion in Cluster 1 and incrementally longer CIT in Cluster 2. Cluster 2 had a higher incidence of delayed graft function (42%vs. 29%), and lower 1-year patient (95%vs. 98%) and death-censored (95%vs. 97%) graft survival compared to Cluster 1. Unsupervised machine learning characterized deceased donor kidney transplant recipients with prolonged CIT into two clusters with differing outcomes. Although Cluster 1 had more favorable recipient and donor characteristics and better survival, the outcomes observed in Cluster 2 were also satisfactory. Overall, both clusters demonstrated good survival suggesting opportunities for transplant centers to incrementally increase CIT.

Effect of donor-recipient size mismatch on long-term graft survival in pediatric kidney transplantation: a multicenter cohort study.

Donor-recipient size mismatching is commonly occurs in pediatric kidney transplantation (KT). However, its effect on graft survival remains unknown. This study aimed to determine the effect of donor-recipient size mismatch on the long-term survival rate of transplant kidneys in pediatric KT. A total of 241 pediatric patients who received KT were enrolled. The medical records of all patients were retrospectively reviewed, and the correlation between donor-recipient size mismatch and graft function and long-term graft outcome was analyzed according to donor-recipient size mismatch. Recipients and donors' mean body weight at the time of KT were 34.31 ± 16.85 and 56.53 ± 16.73 kg, respectively. The mean follow-up duration was 96.49 ± 52.98 months. A significant positive correlation was observed between donor-recipient body weight ratio (DRBWR) or donor-recipient body surface area ratio (DRBSR) and graft function until 1 year after KT. However, this correlation could not be confirmed at the last follow-up. The results of long-term survival analysis using Fine and Gray's subdistribution hazard model showed no significant difference of the survival rate of the transplant kidney according to DRBWR or DRBSR. Donor-recipient size mismatch in pediatric KT is not an important factor in determining the long-term prognosis of transplant kidneys.

Identification of asymptomatic Leishmania infection in patients undergoing kidney transplant using multiple tests

ObjectivesIn immunocompromised patients, asymptomatic Leishmania infection can reactivate, and evolve to severe disease. To date, no test is considered the gold standard for the identification of asymptomatic Leishmania infection. A combination of methods was employed to screen for Leishmania infection in patients undergoing kidney transplant (KT). MethodsWe employed polymerase chain reaction for the detection of parasitic DNA in peripheral blood, Western blot to identify serum immunoglobulin G and whole blood assay to detect cytokines/chemokines after stimulation of whole blood with parasitic antigen. ResultsOne-hundred twenty patients residing in Italy were included in the study at the time of KT. Each patient that tested positive to at least one test was considered as Leishmania positive. Fifty out of 120 patients (42%) tested positive for one or more tests. The detection of specific cell-mediated response (32/111, 29%) was the most common marker of Leishmania infection, followed by a positive serology (24/120, 20%). Four patients (3%) harbored parasitic DNA in the blood. ConclusionOur findings underline the high prevalence of asymptomatic Leishmania infection in patients undergoing KT in Italy, who are potentially at-risk for parasite reactivation and can benefit from an increased vigilance. Understanding the clinical relevance of these findings deserves further studies.

Importance of Frailty in Kidney Transplant Recipients

Frailty is a persistent chronic inflammatory syndrome present in many patients with chronic kidney disease. After kidney transplant (KT), it has been associated with complications such as delayed graft function, hospital readmission, or poorer KT survival. To assess the impact of frailty on the results of KT. Longitudinal prospective study of 65 patients included on the waiting list (WL) between October 2019 and October 2021. We used the FRAIL scale and recorded clinical characteristics, including demographic, dependency scales, and analytical parameters at the moment of the inclusion on the WL and at months 3 and 12 after KT. The mean age was 58 years old, and 70% of KT were men. The comorbidity burden was 26% diabetes, 83% hypertension, and 12% ischemic heart disease. Forty patients (61.5%) presented ≥1 point on the FRAIL scale, and 25 (38.4%) were robust. Frail patients (FRAIL score≥3) had a higher Charlson comorbidity index at the time of KT, a lower Barthel index, and a lower quality of life measured by KDQOL-36. No significant differences were observed in other variables, such as days of admission, surgical complications, or delayed graft function. There were 3 graft losses censored for death and 4 deaths, all in frail or prefrail patients. These patients had lower graft survival (P=.164) and patient survival (P=.096). At 12 months post KT, frailty improved in 67% of patients evaluated. Frailty is a common condition among patients on the WL, leading to poorer quality of life, greater dependency, and a higher risk of graft loss and mortality. Frailty conditions can be reversed in many patients after KT.

89 Frailty in Renal Transplantation: Retrospective Cohort Study to Examine the Impact of the New 2019 Kidney Offering Scheme on Older Transplant Recipients

Abstract Background In 2019, a new kidney offering scheme was launched in the United Kingdom, aiming to better match estimated patient survival and graft life expectancy. The impact of the scheme on older patients undergoing kidney transplantation (KT) is unknown. Aim This study aims to compare outcomes of elderly KT recipients before and after the introduction of the 2019 kidney offering scheme. Method A retrospective cohort study of two groups of elderly patients who underwent KT was undertaken. Group 1 included patients transplanted between 01/09/2017 and 31/08/2019 as part of the “2006 allocation scheme”. Group 2 included patients transplanted between 01/09/2019 and 31/08/2021 as part of the “2019 offering scheme”. An elderly patient was defined as any person over 60 years of age at the time of KT. Univariate binary logistic regression analysis was performed to determine odds ratios (OR) and 95% confidence intervals. Results There were 107 elderly deceased donor KT recipients; 62 from Group 1 and 45 from Group 2. The median age at transplantation was 68 years (62-71) and 67 years (64-73), respectively. Univariate analysis showed that level four HLA mismatch (OR 4.667 95%CI 1.640-13.275, p = 0.004) and a requirement for re-intervention (OR 6.496 95%CI 1.306-32.216, p = 0.022) were significantly more likely in the 2019 offering scheme. One year graft survival worsened on introduction of the 2019 offering scheme (85% vs 80%). Conclusions The introduction of the 2019 offering scheme has led to less favourable HLA matches, increased need for reintervention, and a lower one-year graft survival in elderly KT recipients.

Does obesity really affect renal transplantation outcomes?

IntroductionKidney transplantation is the treatment of choice for patients with stage 5 chronic kidney disease (CKD). About 60% of CKD patients are overweight or obese at the time of kidney transplantation, and post-transplant obesity occurs in 50% of patients, with a weight gain of 10% in the first year and high risk of cardiovascular mortality. Obesity is associated with an increased risk of delayed graft function (DGF), acute rejection, surgical complications, graft loss and mortality. The aim of this study is to assess the clinical evolution of obese and overweight patients that have received a kidney transplant, based on short- and long-term complications associated with a higher BMI. Material and methodsA descriptive, observational, cross-sectional study was conducted with 104 kidney or pancreas-kidney transplant patients between March 2017 and December 2020, with a follow-up until April 2021. For comparative analysis, patients were grouped according to BMI. ResultsMean age was of 56.65 years, 60.6% male and 39.4 % female. Overweight patients experienced prolonged surgeries, more surgical wound dehiscence, delayed graft function, hernias, proteinuria and more indications for renal biopsies. Additionally, obese patients displayed more DGF, indications for renal biopsies, proteinuria, development of diabetes mellitus, atrial fibrillation and needed prolonged hospital stays. ConclusionsDespite a high prevalence of comorbidity in the overweight and/or obese population, we found no reduction in patient and/or graft survival. However, longer follow-up is needed.