Prediction of kidney transplant outcome based on different DGF definitions in Chinese deceased donation

The differential impact of early graft dysfunction in kidney donation after brain death and after circulatory death: Insights from the Dutch National Transplant Registry

Kidneys donated after circulatory death (DCD) perform similarly to kidneys donated after brain death (DBD). However, the respective incidences of delayed graft function (DGF) differ. This questions the donor type-specific impact of early graft function on long-term outcomes. Using competing risk and Cox-regression analysis, we compared death-censored graft loss between types of early graft function: DGF (temporary dialysis dependency started within 7 days after transplantation), slow graft function (3-day plasma creatinine decline less than 10% per day), and immediate graft function. In 1061 DBD and 1605 DCD graft recipients (January 2014 until January 2023), graft survival was similar. DGF was associated with death-censored graft loss in DBD and DCD (adjusted hazard ratios: DGF in DBD: 1.79 [1.04-2.91], P = .027, DGF in DCD: 1.84 [1.18-2.87], P = .008; Reference: no DGF). Slow graft function was associated with death-censored graft loss in DBD, but not significantly in DCD (adjusted hazard ratios DBD: 2.82 (1.34-5.93), P = .007, and DCD: 1.54 (0.72-3.35), P = .262; Reference: immediate graft function). Early graft dysfunction has a differential impact on graft outcome in DBD and DCD. The differences between DBD and DCD should be accounted for in research and the clinic.

Development and validation of a novel nomogram model for predicting delayed graft function in deceased donor kidney transplantation based on pre-transplant biopsies

BACKGROUND

Delayed graft function (DGF) is an important complication after kidney transplantation surgery. The present study aimed to develop and validate a nomogram for preoperative prediction of DGF on the basis of clinical and histological risk factors.

METHODS

The prediction model was constructed in a development cohort comprising 492 kidney transplant recipients from May 2018 to December 2019. Data regarding donor and recipient characteristics, pre-transplantation biopsy results, and machine perfusion parameters were collected, and univariate analysis was performed. The least absolute shrinkage and selection operator regression model was used for variable selection. The prediction model was developed by multivariate logistic regression analysis and presented as a nomogram. An external validation cohort comprising 105 transplantation cases from January 2020 to April 2020 was included in the analysis.

RESULTS

266 donors were included in the development cohort, 458 kidneys (93.1%) were preserved by hypothermic machine perfusion (HMP), 96 (19.51%) of 492 recipients developed DGF. Twenty-eight variables measured before transplantation surgery were included in the LASSO regression model. The nomogram consisted of 12 variables from donor characteristics, pre-transplantation biopsy results and machine perfusion parameters. Internal and external validation showed good discrimination and calibration of the nomogram, with Area Under Curve (AUC) 0.83 (95%CI, 0.78-0.88) and 0.87 (95%CI, 0.80-0.94). Decision curve analysis demonstrated that the nomogram was clinically useful.

CONCLUSION

A DGF predicting nomogram was developed that incorporated donor characteristics, pre-transplantation biopsy results, and machine perfusion parameters. This nomogram can be conveniently used for preoperative individualized prediction of DGF in kidney transplant recipients.

Assessment of renal quality with quantitative contrast-enhanced ultrasound (CEUS) for differentiating kidney histopathology before procurement

Purpose: This study aimed to investigate the use of contrast-enhanced ultrasonography (CEUS) to assess the kidneys' quality before procurement. Methods: This prospective study included 74 donors and 148 recipients of kidneys. 119 kidneys underwent quantitative analysis. Before organ procurement, potential kidney donors underwent CEUS, though organ procurement involved a zero-point puncture biopsy. CEUS parameters of the renal cortex and medulla were evaluated, including rise time (RT), time to peak (TTP), the area under the curve (AUC), wash-in slope (WIS), peak intensity (PI), and mean transit time (MTT). Donors' kidneys were classified based on their pathological. Additionally, short-term clinical indicators of renal recipients were collected and analyzed to determine whether the patients had delayed recovery of renal allograft function. Results: This experiment included 148 cases of kidney information, divided into two groups based on the Remuzzi score of the kidneys. However, 29 kidneys were excluded from the quantitative analysis due to loss or low quality of CEUS images. Comparing the time-intensity curve (TIC) of renal cortical region of interest (ROI), we found that the group with lower pathological scores exhibited higher PI (P=0.002), AUC(P=0.003), and WIS (P=0.009). TIC comparison results for renal medulla ROI revealed that the group with lower pathological scores had higher PI (P=0.010), AUC (P=0.023), and WIS (P=0.024). Conclusions: This study highlighted the potential of CEUS as a non-invasive, safe, and real-time examination method that correlates with the Remuzzi score and renal pathology. Therefore, it can be used as a prospective preoperative non-invasive evaluation method for the donor's kidney.

HLA B eplet mismatches in the context of delayed graft function and low tacrolimus trough levels are risk factors influencing the generation of de novo donor-specific antibodies and acute rejection in the early stage after kidney transplantation

BACKGROUND

De novo donor-specific antibody (dnDSA) generation and acute rejection (AR) are the main factors affecting long-term graft survival. This study aims to investigate human leukocyte antigen (HLA) eplet mismatching (MM), delayed graft function (DGF), and tacrolimus (TAC) trough levels on the occurrence of dnDSA and AR in the early stages after kidney transplantation (KT).

METHODS

This retrospective study included 526 cases of deceased donation KT. The effects of DGF, HLA eplet MM, and TAC trough levels on dnDSA and AR occurrence were analyzed with logistic regression analysis.

RESULTS

Multivariate logistic regression analysis showed the independent risk factor of dnDSA generation was HLA B eplet MM (OR: 1.201, 95% CI: 1.007-1.431, P = 0.041). The independent risk factors of AR occurrence include DGF (OR: 4.045, 95% CI: 1.047-15.626, P = 0.043), HLA B eplet MM (OR: 1.090, 95% CI: 1.000-1.187, P = 0.050), and TAC trough levels at 12 months (OR: 0.750, 95% CI: 565-0.997, P = 0.048). HLA B eplet MM combined with DGF and TAC trough levels at 12 months increased the predictive value of dnDSA (AUC 0.735) and AR (AUC 0.730) occurrence. HLA B eplet MM > 9 and TAC trough levels below 5.95 ng/mL at 12 months could increase the risk of early AR occurrence.

CONCLUSIONS

HLA B eplet MM, DGF, and TAC trough levels at 12 months after KT could affect the occurrence of dnDSA and AR in the early stage of KT.

Birc3 and Tip1 are upregulated in renal ischemia reperfusion injury

Identification of ischemia-reperfusion injury (I/R)-associated genes is essential for exploring I/R novel mechanisms. Previously, we screened differentially expressed genes in renal I/R mouse models and found that Tax1 binding protein 3 (Tip1) and baculoviral IAP repeat containing 3 (Birc3) are two upregulated genes in I/R. In the present study, we analyzed the expression of Tip1 and Birc3 in I/R models. We found that the expression of Tip1 and Birc3 was upregulated in I/R-treated mice, whereas Tip1 was downregulated and Birc3 was upregulated in oxygen-glucose deprivation/reoxygenation (OGD/R) in vitro models. By inhibiting Birc3 with AT-406 in I/R-treated mice, we observed that the serum creatinine or blood urea nitrogen did not vary. However, inhibition of Birc3 enhanced apoptosis of kidney tissues induced by I/R treatment. Consistently, we found that inhibition of Birc3 also increased the apoptosis rate in tubular epithelial cells induced by OGD/R. These data demonstrated that Tip1 and Birc3 were upregulated in I/R injury. The upregulation of Birc3 may protect against renal I/R injury.

Transplant of Kidneys From Hepatitis C Virus-Positive Donors To Hepatitis C Virus-Negative Recipients: A Retrospective Study and Systematic Review

OBJECTIVES

Kidneys from hepatitis C virus-positive donors were often discarded due to the lack of an effective treatment for hepatitis C virus. However, the advent of direct-acting antivirals has facilitated great progress for treatment of hepatitis C virus, providing additional opportunities for patients waiting for kidney transplant. We explored the feasibility and safety of kidney transplant from hepatitis C virus- positive donors to hepatitis C virus-negative recipients in combination with direct-acting antiviral therapy.

MATERIALS AND METHODS

This was a single-center retrospective study of 7 recipients of hepatitis C virus- positive kidneys from June 2018 to June 2021. All recipients were treated with sofosbuvir/velpatasvir for 12 weeks after kidney transplant. The primary recipients' outcome was achievement of sustained viral eradication at 12 weeks after treatment, and follow-up secondary outcomes were kidney function recovery, liver function, and adverse drug reactions. We reviewed previous studies, from 2017 to 2022, to analyze achievement of sustained viral eradication at 12 weeks after treatment, recipient and graft survival, and adverse event of kidney transplant from a hepatitis C virus-positive donor to a hepatitis C virus-negative recipient.

RESULTS

Median follow-up time was 71 weeks (range, 56-183 weeks). All recipients achieved sustained viral eradication at 12 weeks after treatment, and their kidney function recovered without severe liver damage or adverse drug reactions. Previous studies suggested that transplant of hepatitis C virus-positive donor kidneys is safe and feasible when combined with direct-acting antiviral therapy. However, details regarding optimal duration of treatment and directacting antiviral regimen remain undetermined, so prospective randomized studies are warranted.

CONCLUSIONS

Our study further confirms that kidney transplant from hepatitis C virus-positive donors to hepatitis C virus-negative recipients is safe and feasible with direct-acting antiviral treatment. Grafts from hepatitis C virus-infected donors may be effective to resolve the problem of kidney shortage.

Long-term outcomes of kidney transplantation from expanded criteria donors with Chinese novel donation policy: donation after citizens' death

Introduction

The Chinese Government initiated the Donation after Citizens' Death policy in 2010. To now, it has been a major source of organs for transplant. Since it is still a young policy, corresponding clinical evidence is still urgently needed for its improvement. Compared to kidneys donated by SCD (standard criteria donor), increasing the use of ECD (expanded criteria donor) derived kidneys is a way to expand the donor pool but is also a result of the aging demography of China. This study is based on the data of kidney transplantation in our center with the Donation after Citizens' Death policy, aiming to provide a reference for the clinical use of ECD kidneys.

Method

A retrospective study enrolled 415 kidney transplants derived from 211 donors performed between October 2011 and October 2019. A total of 311 (74.9%) organs were donated from 159 (75.4%) SCDs, and the remaining 104 (25.1%) were from 52 (24.6%) ECDs. The log-rank test was used to compare the difference in survival and postoperative complications. The Chi-square test was used to compare the occurrence of postoperative complications and postoperative renal function. The Cox regression analysis was used for risk factor screening.

Result

Analysis showed that grafts from ECD were poorer in survival (P = 0.013), while their recipients had comparable (P = 0.16) survival. Moreover, it also was an independent risk factor for graft loss (HR 2.27, P = 0.044). There were significantly more AR occurrences in the ECD group compared with SCD group (25.0% vs. 15.8%, P = 0.004), but no significant difference was found in infection (51.9% vs. 47.6%, P = 0.497) and DGF (26.0% vs. 21.9%, P = 0.419) between them. Similarly, fewer recipients in the ECD group were free from AR within 1 year after transplantation (P = 0.040), with no statistical difference in all-cause infection prevalence in 1 year (P = 0.168). The eGFR in the ECD group was significantly worse than that in the SCD group at 3 months, 6 months, 1 year, 3 years, and the highest value posttransplant (all < 0.05), but no difference at 5 years posttransplant. Besides, results showed cardiac arrest (uncontrolled vs. controlled, HR 2.49, P = 0.049), HLA mismatch (4–6 loci vs. 0–3 loci, HR 3.61, P = 0.039), and AR occurrence (HR 2.91, P = 0.006) were demonstrated to be independent risk factors for graft loss.

Conclusion

The ECD-derived kidney was worse than the SCD-derived kidney in terms of graft survival and AR occurrence, and trend to an inferior renal function postoperative. However, the recipient survival, DGF occurrence, and all-cause infection occurrence were similar.

Predictive value of the renal resistive index in the immediate postoperative period after kidney transplantation on short- and long-term graft and patient outcomes

INTRODUCTION

During the postoperative stay in the intensive care unit after kidney transplantation, the renal resistive index (RI) is routinely measured. An increased RI, measured months posttransplant, is associated with a higher mortality. We wanted to investigate the value of the RI immediately posttransplant in predicting both short- and long-term outcome.

METHODS

We performed a retrospective single-center study. The RI was collected <48 h posttransplant in patients undergoing kidney transplantations between 2005 and 2014. Short-term outcome was evaluated by delayed graft function (DGF). The long-term endpoints were kidney function and mortality at 30 days, 1 year and 5 years.

RESULTS

We included 478 recipients, 91.4% of whom reached the end of the 5-year follow-up. A higher RI < 48 h posttransplant was significantly associated with DGF. This association was particularly strong in patients receiving grafts from donors after brain death and expanded criteria donors. A higher RI also correlated with mortality and death with functioning graft but not with graft failure. After adjustment for confounders, we found an association between increased RI and DGF, but not with long-term kidney function or mortality.

CONCLUSION

The RI routinely measured <48 h posttransplant is an independent predictor of short-term kidney function.

Risk factors for renal allograft survival with China novel donation category: Donation after brain death followed by cardiac arrest

INTRODUCTION

To meet the need for transplantable organs, a new donation program was initiated by the Chinese government. This novel policy created three categories for deceased organ donations: donation after circulatory death cardiac death (DCD), donation after brain death (DBD), and donation after brain death followed by circulatory death (DBCD) meaning complete cardiac arrest. In fact, the DBCD method is a combination of both DBD and DCD methods. A DBCD donor meets the criteria of for brain death, but the organ procurement begins after the withdrawal of life support and the subsequent cardiac arrest death. The purpose of this study was to evaluate the long-term outcomes of kidney transplantation in our center with the DBCD policy. Potential risk factors for affecting the renal allograft survival were also analyzed based on our data.

METHOD

A retrospective study, involving 421 kidney transplants derived from 214 donors, was conducted between December 2011 and October 2019. In particular, 373 (88.6%) transplanted organs met the criteria for DBCD, and 48 (11.4%) for DCD. The log-rank test was used to compare the difference in survival. The Cox regression analysis was used for risk factor screening.

RESULT

Analysis showed that the DBCD group was better than the DCD group in terms of overall (p = 0.031) as well as death-censored (p = 0.026) allograft survival using the log-rank test. A Cox regression analysis revealed that increasing donor age (p = 0.002, HR = 1.820/10 years incremental older), increasing recipient age (p = 0.028, HR = 1.521/10 years increment older), prolonged dialysis duration (p = 0.007, HR = 1.018), occurrence episodes of acute rejection (p = 0.016, HR = 2.697), delayed graft function (p = 0.012, HR = 2.962), mismatch ≥4 HLA loci (p = 0.038, HR = 3.606), and warm ischemia time > 15 min (p = 0.022, HR = 2.915), were all independent risk factors affecting the graft survival.

CONCLUSION

The new DBCD policy of donation produced acceptable results similar or even better than the DCD practice. Based on our analysis, the graft survival of DBCD transplants may be better than DCD transplants. The main risk factors for allograft loss included an increasing donor age, recipient age, warm ischemia time > 15 min, prolonged dialysis duration, acute rejection, delayed graft function, and HLA mismatch ≥4 HLA loci.

Effect of Delayed Graft Function on the Outcome and Allograft Survival of Kidney Transplanted Patients from a Deceased Donor

BACKGROUND

In kidney transplantation (KT), delayed graft function (DGF) is a significant early complication observed in the first week. The study aimed to investigate the impact of DGF on the outcome, allograft, and patient survival after KT with organs from deceased donors.

METHODS

This retrospective study was conducted using 304 KT patients who received an organ from deceased donors from 2008 to 2018. The patients were divided into 2 groups, DGF positive (DGF⁺) and DGF negative (DGF^-). The database containing the clinical, laboratory, and immunologic information of donors and recipients was statistically analyzed using the SSPS program.

RESULTS

In this study, 189 (62.17%) were DGF⁺ and 115 (37.83%) were DGF^-. Until 6 months after KT, the estimate glomerular filtration rate was better in group DGF^-, but it was similar between the groups during 10-year follow-up. Graft losses were higher in DGF⁺ group than in the DGF^- (P = .046). The serum creatinine level was persistently higher in DGF⁺ group until the sixth month (P ≤ .05). Allograft survival rates were better in patients who were DGF^- (P = .033). Those who had DGF for more than 15 days had a worse graft survival (P = .003), but in 10 year follow-up, patient survival rates were similar (P = .705).

CONCLUSION

DGF⁺ patients were associated with dialysis time before KT, ischemia time, and the donors' clinical status, such as age, organ quality, and serum creatinine. All these factors had a great impact on graft survival but not on patient survival.

Long Hemodialysis Duration Predicts Delayed Graft Function in Renal Transplant Recipients From Living Donor: A Single-Center Study

BACKGROUND

This study aims to determine the ratio of delayed graft function in renal transplant recipients from living donors and the predictive value of hemodialysis time before transplant for delayed graft function.

METHODS

We conducted a study on 116 adult patients who were diagnosed with end-stage kidney disease and were treated with hemodialysis and transplanted kidneys from living donors for 2 years (from June 2018 to June 2020). Delayed graft function event was collected for each patient.

RESULTS

The recipients had a median age of 36.5 years old, in which 55.2% of them were men, 4.3% of them had the diabetic mellitus, and the median hemodialysis duration was 6 months. The ratio of positive panel-reactive antibody was 33.6% and vascular reconstruction of the donor's kidney was 16.4%. The ratio of delayed graft function was 12.2% (14 of 116 patients). Delayed graft function significantly related to positive panel-reactive antibody, long duration of hemodialysis before transplant, and vascular reconstruction of donor's kidney with P < .001. Duration of hemodialysis before kidney transplant had a predictive value for delayed graft function (area under the curve, 0.83; P < .001).

CONCLUSION

Delayed graft function was not rare in renal transplant recipients from living donors. Duration of hemodialysis before kidney transplant was a good predictor for delayed graft function.

The impact of functional delayed graft function in the modern era of kidney transplantation - A retrospective study

The dialysis-based definition of Delayed Graft Function (dDGF) is not necessarily objective as it depends on the individual physician's decision. The functional definition of DGF (fDGF, the failure of serum creatinine to decrease by at least 10% daily on 3 consecutive days during the first week post-transplant), may be more sensitive to reflect recovery after the ischemia-reperfusion injury. We retrospectively analyzed both definitions in 253 deceased donor kidney transplant recipients for predicting death-censored graft failure as primary outcome, using eGFR < 25 ml/min/1.73 m² as a surrogate end-point for graft failure. Secondary outcome was a composite outcome that included graft failure as above and also patient's death. Median follow-up was 3.22 [2.38-4.21] years. Seventy-nine patients developed dDGF (31.2%) and 127 developed fDGF (50.2%). Sixty-three patients fulfilled criteria for both definitions (24.9%). At multivariable analysis, the two definitions were significantly associated with the primary [HR (95%CI) 2.07 (1.09-3.94), P = 0.026 for fDGF and HR (95%CI) 2.41 (1.33-4.37), P = 0.004 for dDGF] and the secondary composite outcome [HR (95%CI) 1.58 (1.01-2.51), P = 0.047 for fDGF and HR (95%CI) 1.67 (1.05-2.66), P = 0.028 for dDGF]. Patients who met criteria for both definitions had the worst prognosis, with a three-year estimates (95%CI) of survival from the primary and secondary outcomes of 2.31 (2.02-2.59) and 2.20 (1.91-2.49) years for fDGF+/dDGF+, in comparison with the other groups (P < 0.01 for trend). fDGF provides supplementary information about graft outcomes on top of the dDGF definition in a modern series of kidney transplantation.

Analysis of Factors Influencing Kidney Function of Recipients After Renal Transplantation in Southwestern China: A Retrospective Study

Background: Factors influencing the kidney function of patients after renal transplantation include both recipient-related factors and donor-related factors. To gain a better understanding of these factors and to improve clinical decision-making, we performed a retrospective study of southwestern Chinese people receiving kidney transplantation.

Methods: In this retrospective analysis, a total of 2,462 recipients receiving allogeneic kidney transplantation in West China Hospital of Sichuan University from December 13, 2008 to January 10, 2018 were included. Data on recipient and donor characteristics were extracted from the Transplant Center Database and stratified by discrete time points after kidney transplantation. Univariate and multivariate logistic regression analyses were carried out on the study variables, and kidney function of postoperative patients was monitored using cystatin C (CysC) as the outcome indicator.

Results: From the univariate analysis, several factors showed statistically significant short-term impact on kidney function based on CysC after kidney transplantation, including age, ethnicity, body mass index (BMI), and HLA A-B-DR-DQ loci mismatch. Gender of recipients and gender-consistency between donors and recipients revealed both short-term and long-term influence. Younger donors had significantly better medium-and-long-term influence on kidney function. From the multivariate logistic regression analysis, recipient gender, ethnicity, BMI, and donor age were independent factors affecting postoperative CysC recovery at discrete time points.

Conclusion: Several factors of recipients related to renal function after kidney transplantation, such as gender, ethnicity, BMI and donor's age should be paid more attention to. Moreover, female and non-Han recipients decreased the risk of poor outcome during postoperative kidney function recovery while large BMI of recipients and higher donor age increased the risk. It is useful to predict the postoperative renal function earlier according to corresponding factors, and improve the patient's quality of life.