Donor Risk Index Research Articles

Outcomes of liver transplantation using moderately steatotic liver from donation after cardiac death (DCD).

BackgroundLiver grafts from donation after cardiac death (DCD) with moderate steatosis (MS) are generally considered unsui for liver transplantation (LT) because DCD and MS are independent risk factors of poor prognosis of LT. Many centers have begun to accept this type of liver graft. However, the clinical outcomes are indeed controversial. This study aimed to examine the outcomes after LT of using such liver grafts.MethodsThis study retrospectively reviewed our experiences in 80 allografts from May 2015 to September 2019. A total of 16 allografts using MS liver grafts from DCD (MS-DCD group) were compared with a matched control group of 64 allografts using a nonsteatotic liver graft (NS group) (1:4 ratio). Postoperative outcomes, including primary nonfunction (PNF), initial poor function (IPF), postoperative complications, and graft/patient survival rates, were extracted for pooled analysis.ResultsRecipient and surgical characteristics of patients and clinical data of donors between MS-DCD group and NS group were balanced. No significant differences were observed in hepatitis B virus (HBV) infection, model for end-stage liver disease (MELD) score, cold ischemia time (CIT), donor risk index, warm ischemia time (WIT). A significant difference was detected in the incidence of initial poor function (IPF) (11/16 vs. 26/64; P=0.02), and the average peak value of aspartate transaminase (AST) (3,469 vs. 1,295; P<0.01) was significantly higher in the steatosis group. Meanwhile, alanine transaminase (ALT) was only higher on day 1, and international normalized ratio (INR) level was only higher on days 1 and 3 and disappeared on day 7. The serum total bilirubin (TB) was the same between the two groups. Postoperative complications were similar between the two groups. The 90-day, 1-year, and 3-year survival rates in patients and grafts between the two groups were similar (patient survival(MS-DCD group vs. NS group): 75% vs. 85.9%, 75% vs. 78.1%, 68.8% vs. 71.9%, log-rank test, P=0.77; graft survival(MS-DCD group vs. NS group): 75% vs. 84.4%, 75% vs. 75%, 68.8% vs. 68.8%, log-rank test, P=0.79).ConclusionsAfter rigorous evaluation, it was found that moderately steatotic liver from DCD is an effective means to expand the source of liver supply.

REASSESSMENT OF THE RELEVANCE AND PREDICTIVE VALUE OF PARAMETERS INDICATING EARLY GRAFT DYSFUNCTION IN LIVER TRANSPLANTATION: A RETROSPECTIVE SINGLE CENTER EXPERIENCE

Background: Early graft dysfunction (EAD) complicates liver transplantation. In the light of changing donor characteristics and machine perfusion, the definition of EAD deserves reevaluation. The aim of this analysis was to discriminate between the single effect of each variable of EAD and to develop a model for individualized risk estimation for the clinical outcome in liver transplantation. Material and Methods: We reviewed all primary LT performed between 2007 and 2018. Exclusion criteria were age < 18 years, living donor transplantation and split grafts. Primary endpoint was the discriminative value of each variable defining EAD, secondary endpoints were risk factors. EAD was recorded when at least one of the following criteria was present: (i) AST levels >2000 IU/L within the first seven days, (ii) bilirubin levels ≥10mg/dL or (iii) INR ≥1.6 on postoperative day 7. EAD parameter were assessed by developing a Cox proportional hazard model. Predictors for EAD were investigated using logistic regression analysis. Survival rates were compared using the Kaplan–Meier method. Results and Discussion: Six-hundred-sixteen LT were included. Of these, 30.7% developed EAD. Patient survival did not differ significantly between groups (P = .09; Log Rank-Test=2.87). Graft survival was significant higher in non-EAD patients (P =.008; Log Rank-Test=7.13). Isolated elevated AST (78%) and bilirubin (8%) were the most frequent variables in EAD recipients. The proportional hazard regression model showed strikingly diverse discriminative value of EAD parameter for prediction of mortality. While Bilirubin was the best predictor (W = 12.64, P < .001 for patient survival; W = 13.17, P < .001 for graft survival), AST did not serve to display a significant discrimination (W = 0.31, P = .580 for patient survival; W = 3.19, P = .074 for graft survival). Comparing the Hazard Ratio (HR) in Cox proportional hazard model, bilirubin and INR were selected as strong mortality predictors (Bilirubin HR = 1.71 1.34, 2.16]; INR HR = 2.69 [0.51, 14.31]), while AST did not reach significant effect (HR = 0.91 [0.75, 1.10]) suggesting a categorized discrimination potential in EAD status. Similar results were achieved for graft loss estimation (Bilirubin HR = 1.44 1.16, 1.79]; INR HR = 2.37 [0.58, 9.72]; AST HR = 1.11 [0.93, 1.33]. Child B Score, Child C Score, surgery duration, regional allocation, cold ischemia time, donor risk index and donor BMI > 25 were independent risk factors for EAD in this study. AST levels as primary endpoint poorly reflect graft and patient survival, while bilirubin and INR have strong predictive capacity. This fits well with the idea that bile duct injury and deprivation of synthetic function rather than hepatocyte injury are key factors in liver transplantation.Conclusion: New insights into the utility of EAD were presented. For an individualized risk estimation, we propose reconsideration of the EAD definition.

Changing Population of Liver Transplant Recipients in the Era of Direct-acting Antiviral Therapy.

Background and Aims: With the availability of direct-acting antiviral (DAA) therapy for hepatitis C virus (HCV) infection and changing liver disease etiology for liver transplantation (LT), data on the changes in LT recipient population in the DAA era are scanty.Methods: The United Network for Organ Sharing (UNOS) registry (01/2007 to 06/2018) was used to develop a retrospective cohort of LT recipients for HCV, alcohol-associated liver disease (ALD), and non-alcoholic steatohepatitis (NASH). LT recipients in the DAA era (2013-2018) were compared with those in the pre-DAA era (2007-2012) era for recipient characteristics. Chi-square and analysis of variance were the statistical tests used for categorical and continuous variables, respectively.Results: Of 40,309 LT recipients (21,110 HCV, 7586 NASH, and 11,713 ALD), the 21,790 in the DAA era (9432 HCV, 7240 ALD, and 5118 NASH) were more likely to be older, female, obese, diabetic, have acute-on-chronic liver failure with a higher model for end-stage liver disease score, receive grafts with a lower donor risk index, and have waited on the LT list for a shorter period compared with their pre-DAA era counterparts. Specific to ALD, LT recipients with alcohol hepatitis were more likely to be younger at the time of LT. Of 9895 LT recipients with hepatocellular carcinoma, recipients in the DAA era were observed to have a higher proportion of HCV (43% vs. 32%, p<0.001), a lower proportion of ALD (9% vs. 12%, p<0.001), and no change for NASH (13% vs. 13%, p=0.9) compared with the pre-DAA era. Within the hepatocellular carcinoma population, LT recipients in the DAA era were older, diabetic, and waited on the LT list longer compared with their pre-DAA counterparts.Conclusions: Along with changing liver disease etiology in the DAA era, the LT recipient population demographics, comorbidities, liver disease severity, and graft quality are changing. These changes are relevant for future studies, immunosuppression, and post-transplant follow-up.

Trends in Outcomes for Marginal Allografts in Liver Transplant

Investigating outcomes after marginal allograft transplant is essential in determining appropriate and more aggressive use of these allografts. To determine the time trends in the outcomes of marginal liver allografts as defined by 6 different sets of criteria. In this case-control, multicenter study, 75 050 patients who received a liver transplant between March 1, 2002, and September 30, 2016, were retrospectively analyzed to last known follow-up (n = 55 395) or death (n = 19 655) using the United Network for Organ Sharing Database. The study period was divided into three 5-year eras: 2002-2006, 2007-2011, and 2012-2016. Kaplan-Meier survival analysis with log-rank test and Cox proportional hazards regression analysis were used to examine the allograft after transplant with marginal allografts, which were defined as 90th percentile Donor Risk Index allografts (calculated over the entire study period), donor after circulatory death allografts, national share allografts, old age (donors >70 years) allografts, fatty liver allografts, and 90th percentile Discard Risk Index allografts. Statistical analysis was performed from August to December 2019. Allograft failure after transplant as defined by the Organ Procurement and Transplantation Network database. Among the 75 050 patients (44 394 men; mean [SD] age, 54.3 [9.9] years) in the study, Donor Risk Index, patient Model for End-stage Liver Disease scores, and balance of risk scores significantly increased over time. Multivariate Cox proportional hazards regression analysis indicated that 90th percentile Donor Risk Index allograft survival increased across the study period (2002-2006: hazard ratio, 1.41 [95% CI, 1.34-1.49]; 2007-2011: hazard ratio, 1.25 [95% CI, 1.17-1.34]; 2012-2016: hazard ratio, 1.10 [95% CI, 0.98-1.24]). Secondary definitions of marginal allografts (donor after circulatory death, national share, old age donors, fatty liver, and 90th percentile Discard Risk Index) showed similar improvements in allograft survival. The study's findings encourage the aggressive use of liver allografts and may indicate a need for a redefinition of allograft marginality in liver transplantation.

Making Every Liver Count: Increased Transplant Yield of Donor Livers Through Normothermic Machine Perfusion.

Normothermic machine perfusion (NMP) enables optimized ex-vivo preservation of a donor liver in a normal physiologic state. The impact of this emerging technology on donor liver utilization has yet to be assessed. NMP of the donor liver and ex-vivo enhancement of its function has been envisioned for decades, however only with recent technological advances have devices been suitable for transition to clinical practice. The present study examines the effect NMP on liver utilization in the United States. The United Network for Organ Sharing database was queried to identify deceased donor livers procured from 2016 to 2019 (n = 30596). Donor livers were divided by preservation method: standard cold-static preservation (COLD, n = 30,368) versus NMP (n = 228). Donor and recipient risk factors, liver disposition, and discard reasons were analyzed. The primary outcome was liver discard rate between 2 groups. A total of 4037 livers were discarded. The NMP group had a 3.5% discard rate versus 13.3% in the COLD group (P < 0.001), and this was despite NMP donors being older (47.7 vs 39.5 years, P < 0.0001), more frequently donation after cardiac death (DCD) (18% vs 7%, P < 0.001), and having a greater donor risk index (1.6 vs 1.5, P < 0.05). The most common reasons for liver discard in the COLD group were biopsy findings (38%), DCD warm ischemic time (11%), and prolonged preservation time (10%). Survival analysis, following propensity score matching, found no significant difference in 1-year overall survival between recipients of NMP versus COLD livers. NMP reduces the discard rate of procured livers despite its use in donors traditionally considered of more marginal quality. NMP maintains excellent graft and patient survival. Broader application of NMP technology holds the potential to generate a significant number of additional liver grafts for transplantation every year, thus greatly reducing the nationwide disparity between supply and demand.

Strategies for liver transplantation during the SARS-CoV-2 outbreak: Preliminary experience from a single center in France.

Liver transplantation (LT) during the ongoing severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) pandemic is challenging given the urgent need to reallocate resources to other areas of patient care. Available guidelines recommend reorganizing transplant care, but data on clinical experience in the context of SARS‐CoV‐2 pandemic are scarce. Thus, we report strategies and preliminary results in LT during the peak of the SARS‐CoV‐2 pandemic from a single center in France. Our strategy to reorganize the transplant program included 4 main steps: optimization of available resources, especially intensive care unit capacity; multidisciplinary risk stratification of LT candidates on the waiting list; implementation of a systematic SARS‐CoV‐2 screening strategy prior to transplantation; and definition of optimal recipient‐donor matching. After implementation of these 4 steps, we performed 10 successful LTs during the peak of the pandemic with a short median intensive care unit stay (2.5 days), benchmark posttransplant morbidity, and no occurrence of SARS‐CoV‐2 infection during follow‐up. From this preliminary experience we conclude that efforts in resource planning, optimal recipient selection, and organ allocation strategy are key to maintain a safe LT activity. Transplant centers should be ready to readapt their practices as the pandemic evolves.

“Does Perioperative Patient Perfusion Obviate the Need for Kidney Machine Perfusion?” A Retrospective Analysis of Patients Receiving a Kidney From “Donation After Circulatory Death” Donors

BackgroundDelayed graft function (DGF) remains a clinically relevant problem in the post-transplant period, especially in patients with a renal graft from a “donation after cardiac death” (DCD) donor. Controversy exists around the optimal perioperative fluid therapy in such patients. These patients may benefit from a perioperative saline loading fluid protocol, which may reduce the risk of DGF. MethodsWe compared 2 cohorts of patients who underwent a renal transplantation with a graft from a DCD donor. From January 2003 until December 2012, patients (N = 46) were hemodynamically managed at the discretion of the care-giving physician, without a preoperative fluid administration protocol (first study period). From January 2015 until March 2019 (N = 26), patients received saline loading before, during, and after kidney transplantation according to a well-defined saline loading fluid protocol (second study period). The relationship between the use of this perioperative fluid protocol and DGF was analyzed using univariable and multivariable logistic regression models. ResultsDGF occurred in 11 of 46 (24%) patients in the first study period and in 1 of 26 (4%) in the second study period (P < .05). In a multivariable model, correcting for cold ischemia time and Kidney Donor Risk Index, the use of a saline loading fluid protocol in the perioperative phase was nearly significantly associated with a decrease in DGF (P = .07). ConclusionIn our DCD transplant population, DGF rates were low. Our data further strongly suggest that implementation of a perioperative saline loading fluid protocol was independently associated with a lower risk of DGF.

Using Artificial Intelligence for Predicting Survival of Individual Grafts in Liver Transplantation: A Systematic Review.

The demand for liver transplantation far outstrips the supply of deceased donor organs, and so, listing and allocation decisions aim to maximize utility. Most existing methods for predicting transplant outcomes use basic methods, such as regression modeling, but newer artificial intelligence (AI) techniques have the potential to improve predictive accuracy. The aim was to perform a systematic review of studies predicting graft outcomes following deceased donor liver transplantation using AI techniques and to compare these findings to linear regression and standard predictive modeling: donor risk index (DRI), Model for End-Stage Liver Disease (MELD), and Survival Outcome Following Liver Transplantation (SOFT). After reviewing available article databases, a total of 52 articles were reviewed for inclusion. Of these articles, 9 met the inclusion criteria, which reported outcomes from 18,771 liver transplants. Artificial neural networks (ANNs) were the most commonly used methodology, being reported in 7 studies. Only 2 studies directly compared machine learning (ML) techniques to liver scoring modalities (i.e., DRI, SOFT, and balance of risk [BAR]). Both studies showed better prediction of individual organ survival with the optimal ANN model, reporting an area under the receiver operating characteristic curve (AUROC) 0.82 compared with BAR (0.62) and SOFT (0.57), and the other ANN model gave an AUC ROC of 0.84 compared with a DRI (0.68) and SOFT (0.64). AI techniques can provide high accuracy in predicting graft survival based on donors and recipient variables. When compared with the standard techniques, AI methods are dynamic and are able to be trained and validated within every population. However, the high accuracy of AI may come at a cost of losing explainability (to patients and clinicians) on how the technology works.

Outcomes of kidney transplantation from elderly deceased donors of a Korean registry

To overcome organ shortage, expanded criteria donors, including elderly deceased donors (DDs), should be considered. We analyzed outcomes of kidney transplantation (KT) from elderly DDs in a nationwide study. In total, data of 1049 KTs from DDs using the database of Korean Organ Transplantation Registry (KOTRY) were retrospectively analyzed based on the age of DDs: age ≥60 years vs. <60 years. Clinical information, graft status, and adverse events were reviewed in DDs and recipients. The mean age of the 1006 DDs was 51.04±10.54 years, and 21.5% of donors were aged ≥60 years. Elderly DDs had a significantly higher prevalence of diabetes and hypertension and higher Kidney Donor Risk Index (KDRI) and Kidney Donor Profile Index (KDPI). The mean age of the recipients was 47.45±14.87 years. Patients who received KT from elderly DDs were significantly older (53.12±15.14 vs. 45.88±14.41, P<0.001) and had a higher rate of diabetes (41.9 vs. 24.4%, P<0.001). Graft outcomes were not significantly different. Renal function was similar between the groups at the time of discharge and at 6 months, 1 year, and 2 years after KT. The rate of delayed graft function (DGF) was not significantly different. Risk factors of DGF were significantly different in DDs aged ≥60 years and <60 years. In the multivariable model, male sex (odds ratio: 3.99, 95% confidence interval: 1.42–11.22; P = 0.009) and KDRI (12.17, 2.23–66.34; P = 0.004) were significant risk factors for DGF in DDs aged ≥60 years. In DDs aged <60 years, thymoglobulin induction (2.62, 1.53–4.48; P<0.001) and continuous renal replacement therapy (3.47, 1.52–7.96; P = 0.003) were significant factors. Our data indicated that graft outcomes, including renal function and DGF, were similar for elderly DDs and DDs aged <60 years. Elderly DDs might be considered tolerable donors for KT, with active preoperative surveillance.

P1633STANDARDIZED REVIEW OF DONOR AFTER BRAIN DEATH KIDNEY OFFERS; A QUALITY IMPROVEMENT PROJECT

Abstract Background and Aims Transplanting renal centres have a duty to use the finite resource of the deceased-donor kidney pool to benefit potential recipients without exposing them to excessive risk. However, there is known variation in centre and clinician practice. This may relate to clinicians’ attitude to risk, knowledge of the recipient and unit culture. Centre differences in acceptability of donor organs is evidenced by variation in NHS blood and transplant registry data. Use of marginal donors has become more frequent, especially for older recipients with higher comorbidity. In the UK this year we will see whether switching to an ‘opt out’ donation law further increases this proportion of donors. We developed a systematic method to retrospectively review donation after brain death (DBD) kidney offers declined by our centre, with the intention of reducing variation in practice between clinicians, and identifying cases where offer acceptance may have been appropriate Method All DBD kidney offers declined by the Richard Bright Renal Service between June 2018 and May 2019 were reviewed. Data were collected by casenotes review and by contact with other transplanting units to establish the outcome of donor kidneys and recipient progress. Reasons for offer decline were recorded. Donor and recipient risk indices (DRI and RRI) were calculated. For patients now transplanted, the DRI of the declined offer was compared to the DRI of the transplanted kidney. Results During the study period, 98 DBD kidneys were declined. A donor organ identifier was not available in 8 cases, so 90 are considered here. Average donor age was 57 years with 52% having a Donor Risk Index (DRI) score of 4, and 74.7% a DRI score ≥3. The most common reasons for organ decline were donor related (65%), of which 27% were due to poor kidney function and 22% age mismatch; or recipient related (35%), where 30% were deemed inadequate quality for the recipient and 30% were unavailable or unwell. Of those kidneys which were transplanted elsewhere, 88% were functioning at 6 months with a median creatinine of 119 (IQR 106-148). There were 60 potential recipients, 61% of whom had a RRI score ≥3; 44% had a RRI equal to or less than the DRI of the declined organ. Those who have still not been transplanted have accrued a median of 352 extra days on dialysis. 31 recipients (52%) have been transplanted since their declined offer. The median change in DRI score from the declined offer to the accepted offer was -1 (IQR -2 to 1), and offers were accepted after a median of 45 (IQR 14-143) additional dialysis days. Of those who were transplanted after declining a donor offer, 11 (39%) received a kidney from a donor with equal or worse DRI than the original offer, after a median of 49 further days on dialysis. Conclusion This review process highlights the effect of kidney offer decline on future progress of the potential recipient, as well as differences in our centre practice compared to other centres. Key to this review is to highlight the risks involved with DBD organ decline- 18% of recipients ultimately received an equal or inferior kidney while accruing additional time on dialysis. Alongside this review we have implemented strategies including a policy on AKI in donors and monthly multidisciplinary meetings to discuss individual DBD decline cases. We aim to standardize decision making and increase our utilization of all as well as marginal DBD organs, and expect to show a reduction in variation in practice in future reviews. Use of this process in other units or at a national level could reduce unwarranted variation in the utilization of the donor organ pool.

P1725USAGE AND OUTCOMES FOR EXPANDED CRITERIA DONOR KIDNEY TRANSPLANTATION IN THE KOREA CHARACTERIZED BY KIDNEY DONOR PROFILE INDEX, SINGLE CENTER STUDY

Abstract Background and Aims The demand for Kidney transplantation (KT) is increasing and the number of patients who are waiting for KT is steadily increasing. Therefore, there is an increasing prevalence of KT done by cadaver donor especially, expanded criteria donor. We used Kidney Donor Profile Index (KDPI) to predict the renal prognosis of expanded criteria donor (ECD) KT recipient. Method We investigated patients undergo KT by ECD from March 2013 to June 2018 respectively. Through the donor’s last creatinine level, KDPI score, and Kidney Donor Risk Index (KDRI) score the renal survival rate was compared with ROC curve analysis. Results The mean age of a total 59 ECD KT recipient is 53.85 ± 9.9 years old. Mean follow up duration after KT was 35.0 ± 18.5 months. 10 patients had KDPI score above 85 (KDPI ≥ 85). Five cases undergo dialysis after KT. Nine cases expired during follow up (four sepsis, three sudden cardiac arrest, one hyperkalemia). Glomerular filtration rate one year after KT was significantly associated with KDPI (r=-0.772, p&amp;lt;0.001). The area under curve (AUC) of KDPI was 0.700 (95% CI 0.494-0.906) and cut off point was 75.5. All renal survival patients had KDPI score below 75.5 Conclusion Our results show that KDPI could be used as an indicator for predicting the prognosis of the Korean ECD KT.

P1618DEVELOPMENT AND EXTERNAL VALIDATION OF A PREDICTION MODEL FOR ADVERSE OUTCOME FOLLOWING KIDNEY TRANSPLANTATION FROM OLDER DECEASED DONORS

Abstract Background and Aims With rising demand for kidney transplantation and the kidney donor pool lagging behind, the acceptance criteria for donor kidneys are expanding. Hence, reliable pre-transplant assessment of organ quality has become a top priority. Estimating the risk of adverse outcomes at the time of kidney allocation is challenging and particularly relevant for recipients of kidneys from older donors. The existing kidney donor risk index (KDRI) has been criticized for heavily depending on donor age. Therefore, the aim of the current study was to develop and validate a prediction model for adverse outcome after kidney transplantation from deceased donors aged 50 years or older and compare this model’s performance to the KDRI. Method We utilized the Dutch kidney transplant registry (NOTR) and identified patients who received a kidney from a deceased donor aged 50 years or older between 2006 and 2019. These recipients were included for model development and temporal validation. The prediction model was externally validated on the United States organ transplantation registry (OPTN), in which we selected patients that were transplanted between 2006 and 2017. Potential pre-transplant predictors were selected by an expert panel of nephrologists and surgeons. The predicted adverse outcome was defined as a composite of graft failure, recipient mortality or CKD stage 4/5 within 1 year of transplantation. A logistic regression model was developed, internally validated and shrunk for optimism through bootstrapping. Missing data were multiply imputed in 10-fold, non-linear continuous predictors were modelled with restricted cubic splines and clinically relevant interaction terms were included. The KDRI was validated on the same NOTR and OPTN cohorts for graft survival within 1 year. The developed model and the KDRI were recalibrated to the baseline risk of outcome in external validation. Model performance was assessed by discrimination and calibration. Results The model was developed on 2510 patients of whom 823 experienced an adverse outcome within the first year. The temporal validation cohort contained 837 patients of whom 230 had an adverse outcome and the US external validation cohort consisted of 31987 patients with 6758 adverse outcomes. Selected donor predictors were: age, gender, BMI, cause of death, CPR, inotropes use, serum creatinine, hypertension, hypotension, diabetes, smoking, left/right kidney, warm ischemic time, cold ischemic time and proteinuria. Recipient predictors were: age, gender, BMI, diabetes, cardiovascular comorbidity, primary kidney disease, dialysis duration, number of previous kidney transplantations, HLA mismatches and PRA. Discrimination of the adverse outcome model was moderate, yet considerably better than discrimination of the KDRI (see table). The adverse outcome model’s calibration and distribution of predicted risks were good in both the NOTR and OPTN (see figure). Conclusion A prediction model was developed and extensively validated for adverse outcome after kidney transplantation from older deceased donors. Despite the use of advanced and robust methodology, its discriminatory capacity was limited. However, the adverse outcome model showed good calibration and performed considerably better than the KDRI in this population of suboptimal donors. This model could potentially assist nephrologists in deciding whether to accept or decline a specific kidney from an older deceased donor.

P1629THE COMBINATION OF KDRI AND THE HISTOLOGICAL SCORE IMPROVES THE RISK STRATIFICATION OF MARGINAL ORGANS IN KIDNEY TRANSPLANTATION

Abstract Background and Aims The organ shortage has led to increase the procurement of kidneys from marginal donors, but the risk of graft failure is still object of debate. The aim of the study is to assess whether using both clinical and histological scores can better assess the risk for worse outcome for marginal organs. Method We analyzed 210 kidney transplant recipients from donors aged &amp;gt;50 years. We retrospectively calculated the Kidney Donor Risk Index (KDRI) for each donor and we divided the population according to the KDRI (-, if KDRI ≤ median; +, if KDRI &amp;gt; median) and the histological score (HS, -, if HS ≤ 3; +, if HS &amp;gt; 3) in 4 groups: KDRI-HS- (low KDRI and HS), KDRI-HS+ (low KDRI and high HS), KDRI+HS-(high KDRI and low HS) and KDRI+HS+ (high KDRI and HS). We compared graft function between groups at 2 years and Cox regression analysis was performed to assess the risk for end stage renal disease (ESRD) between groups. Results Overall, median KDRI was 1.44 (1.25-1.65), while mean total HS was 3.04±1.62. Median follow-up was 51.9 (26.4 – 99.4) months. Graft function at 2 years was significantly worse in groups with high KDRI (KDRI+HS- and KDRI+HS+) compared to those with low KDRI (p&amp;lt;0.001), while no differences were found according to the HS. By contrast, the best ROC curve in predicting the development of ESRD is for the model that included both KDRI and histological score (AUC 0.81, 95%CI 0.708-0.914, p&amp;lt;0.001). A Cox model adjusted for recipient age, gender, acute rejection, DGF and chronic allograft dysfunction, patients with high KDRI and high HS are more likely to develop ESRD compared to the other groups (OR 5.6, 95%CI 1.3 to 24.5, p=0.02)(Figure 1). Conclusion Patients with high KDRI and HS have worse outcome compared to patients with high KDRI but better histology. The integration of histology to clinical score may improve the assessment of the risk for graft failure in patients receiving organs from marginal donors.

P1688THE IMPACT OF KIDNEY DONOR PROFILE INDEX (KDPI) AND KIDNEY DONOR RISK INDEX (KDRI) ON KIDNEY TRANSPLANT FUNCTION: A MONOCENTRIC ANALYSIS AFTER ONE YEAR OF FOLLOW UP

Abstract Background and Aims Evaluation of kidney donors is a complex process based on the elaboration of clinical, laboratory and imaging data. Until 2014, the quality of kidney transplant (KTx) was assessed considering standard donation criteria (SCD) or extended donation criteria (ECD). ECD kidneys (kECD) defined subjects older than 65 years without comorbidities or younger, but with comorbidities, such as hypertension, cerebral stroke, high creatinine level (above 1.5 mg/dL). The Kidney Donor Risk Index (KDRI) is an estimate of the relative risk of post-transplant kidney graft failure from a particular deceased donor compared to a reference donor. The value obtained is than converted in a percentage called KDPI (KDPI ≥85% is considered as similar of a kidney from ECD), which represent the percentage of utilized donor in the last year better than the considered. Italian experience in Donor Cardiac Death (DCD) is growing and doubled last KTx year, reaching 1.1 pmp in 2018, with the 22.5% of donors procured at our center. Our DCD KTx protocol has been active since November 2017, with promising results. We considered only controlled DCD (cDCD) Maastricht Class III. Methods We compared all DCD and DBD KTx performed in the Nephrology Unit of the University Hospital of Modena, Italy, from November 2017 to December 2018. We excluded living donor transplantation and combined liver–kidney transplantation. In this study, only cDCD are considered. We studied KDPI and KDRI score for both DBD and DCD KTx . Comparison between data from DCD and DBD was performed with t – Student and Chi Square test, survival analysis according to Kaplan-Meier and a Pearson correlation between KPI-KDRI and one year graft function was elaborated. ROC curve analysis was performed for KDPI – KDRI and DGF for both groups. A p lower than 0.05 was considered significant. Results A total of 28 DBD KTx, 18 double (64.3%) and 10 single (35.7%) and 7 DCD KTx, 3 double (42.8%) and 4 single (57.2%) were observed during the study. Donors and recipients clinical and immunological characteristics are reported in table1. All of DCD and 64.3% of DBD donors underwent kidney biopsy (Karpinski values are reported in table 1). Induction therapy was with aTG in DCD KTx and ECD DBD KTx and with anti-interleukin-2 receptor monoclonal antibodies in SCD DBD KTx. Maintenance immunosuppression consisted in steroid, tacrolimus and mycophenolic acid. KTx outcomes were reported in table 1 with no differences in both groups between creatinine (p0.3) and eGFR (p0.25). We analyzed KDPI and KDRI values from DBD and DCD KTx and we stratified them as reported in table 2. We found 7 DGF in DBD KTx (85% with KDPI &amp;gt;85% and KDRI &amp;gt;1.5) and only 1 DGF in DCD KTx with KDPI&amp;gt;85% and KDRI &amp;gt; 1.5. We did not find a statistical correlation between KDPI- KDRI and eGFR in both DBD KTx (2 patients died and 3 patients were lost at follow up) (r -0.32, p 0.13; r -0.26, p 0.22) and DCD KTx (r -0.59, p 0.15; r -0.47, p 0.28). (Figure 1) We performed a ROC curve Analysis to investigate the role of KDPI – KDRI and the risk of DGF. We found no statistical correlation in DCD KTx, considering the small sample size (p 0.61) but we found a significant statistical value in DBD KTx (p 0.03 – p 0.02 with a AUC of 0.77-0.78). Survival analysis did not show statistical difference between DBD and DCD (p 0.72), no graft loss in the first year, although two DBD (92.8%) recipients died (1circulatory arrest,1 sepsis), no one died in DCD group. Conclusion cDCD is a valid resource for KTx, with similar outcomes to DBD. This remarks the importance of a multidisciplinary team and a correct selection of donors. We did not find a correlation between KDPI-KDRI and KTX function after one year of follow up in our population for either group.

Women who undergo liver transplant have longer length of stay post-transplant compared with men.

Women on the liver transplant waitlist are at greater risk of hospitalization compared with men, but whether this impacts length of stay (LOS) post-transplant is unknown. We aimed to evaluate gender disparities in post-transplant LOS, an important surrogate of health resource utilization post-transplant. Using the UNOS/OPTN registry, we analysed all non-Status 1 adult deceased donor liver transplant recipients without exception points from 2008 to 2017. Poisson regression associated female gender with post-transplant LOS. Of 27294 transplant recipients, 36% were women. Women were more likely to be hospitalized pretransplant than men (44% vs 39%, P<.01). Post-transplant, women were more likely to have prolonged (≥20d) LOS (25% vs 22%, P<.01). In univariable analysis, female gender was associated with longer post-transplant LOS (IRR 1.09, 95%CI 1.06-1.12, P<.01). Prolonged pretransplant admission was also associated with post-transplant LOS (IRR 1.83, 95%CI 1.77-1.89, P<.01). In multivariable analysis, female gender remained independently associated with post-transplant LOS (aIRR 1.05, 95%CI 1.02-1.08, P<.01), after adjustment for age, UNOS region, insurance type, MELDNa, cirrhosis complications, and donor risk index. Pretransplant hospitalization mediated this relationship, explaining 14.1% (95%CI 9.7%-25.4%) of the total effect. Women who undergo deceased donor liver transplant have increased healthcare utilization in the peritransplant period compared with men. Reducing gender disparities in liver transplantation, including the disproportionate burden of healthcare utilization by women pre- and post-transplant, will require interventions targeted at preventing hospitalization among women on the transplant waitlist and developing tools aimed at better characterizing the severity of end-stage liver disease in women.

Kidney Donor Risk Index Score Is More Reliable Than Kidney Donor Profile Index in Kidney Transplantation From Elderly Deceased Donors

BackgroundIt is unclear whether both Kidney Donor Profile Index (KDPI) and Kidney Donor Risk Index (KDRI) scores can be applied to elderly deceased donors (DDs). This study aimed to compare the predictive values of KDRI and KDPI for the occurrence of delayed graft function (DGF) in kidney transplantation (KT) from elderly DDs. MethodsThe data for 1049 DD KTs from the database of the Korean Organ Transplant Registry were reviewed retrospectively. ResultsThe mean age of the 1049 DDs was 50.94 ± 10.57 years. A total of 224 DDs were ≥60 years old (21.35%). The mean KDRI and KDPI were 1.24 ± 0.40 and 63.58 ± 25.16, respectively. Ninety (8.6%) recipients had DGF postoperatively. The right-skewed distributions of KDRI in both elderly and nonelderly DDs were similar. However, the KDPI curve showed a sharp increase from a KDPI score of 60 in DDs aged ≥60 years. The areas under the curve (AUCs) of receiver operator characteristics (ROC) for KDPI and KDRI were different. In DDs aged <60 years, the estimated AUCs of ROC showed significant values for KDPI (0.577, 95% confidence interval, 0.503-0.637; P = .048) and KDRI (0.576, 0.505-0.639; P = .043). However, in DDs aged ≥60 years, KDRI score, not KDPI, was a significant value: KDRI, 0.633 (0.498-0.767; P = .034); KDPI, 0.530 (0.476-0.643; P = .138). ConclusionKDRI was more reliable in predicting graft outcome than KDPI in KT from elderly DDs. A longer follow-up period is needed to assess predictors for postoperative renal functions.

Kidney nonprocurement in solid organ donors in the United States.

There are limited data on the nonprocurement of kidneys from solid organ donors. Analysis of Standard Transplant Analysis and Research files was undertaken on all deceased donors in the United States with at least 1 solid organ recovered. From 2000 to 2018, 21731 deceased donor kidneys (averaging 1144 kidneys per year) were not procured. No kidneys were procured from 8% of liver donors, 3% of heart donors, and 3% of lung donors. Compared to donors with all kidneys procured, those with none procured were older and more likely obese, black, hypertensive, diabetic, hepatitis C positive, smokers, Public Health Service - Increased Risk designated, deceased after cardiac death, or deceased after cerebrovascular accident. Although these donors had lower quality kidneys (median Kidney Donor Risk Index (interquartile range) 1.9 (1.0) vs 1.2 (0.7)), there was substantial overlap in quality between nonprocured and procured kidneys. Nearly one third of nonprocurements were attributed to donor history. Donors with elevated terminal creatinine likely resulting from acute kidney injury (AKI) had higher odds of kidney nonprocurement. Nonprocurement odds varied widely across Organ Procurement and Transplantation Network regions, with a positive correlation between donor kidney nonprocurements and kidney discards at the donationservice area level. These findings suggest current discard rates underestimate the underutilization of deceased donor kidneys and more research is needed to optimize safe procurement and utilization of kidneys from donors with AKI.

Kidney Donor Profile Index in a Transplant Center in Mexico

BackgroundThe Kidney Donor Profile Index (KDPI) was created in 2014 to measure the likelihood of graft failure for a given donor compared with the median kidney donor from the previous year. This scale is based on the American population only. Mexico is one of the countries with greater incidence of chronic kidney disease, a long waiting list, and not enough kidney donors with KDPI smaller than 80%. This has led transplant centers to take kidney grafts with a higher KDPI. ObjectiveTo investigate the agreement between the KDPI and histologic scores (preimplantation renal biopsy) and assess the relationship between the Kidney Donor Risk Index (KDRI), KDPI, and the histologic score on graft survival. MethodsA retrospective, analytical, transversal study was performed. Data were collected from patients with kidney grafts from deceased donors from January 1, 2011, to June 30, 2019, at our hospital. The variables analyzed were age, weight, height, sex, race and/or ethnicity, history of hypertension or diabetes, cause of death, serum creatinine, KDPI, KDRI, and biopsy result from each graft prior to transplant. ResultsThe total population was 59 deceased kidney donors. For our patients, a high KDPI did not increase mortality rate; it provided greater benefit than staying on dialysis. ConclusionsWe conclude that the use of KDRI should only be considered to assess the degree of fibrosis, not to rule out a transplantable kidney, in addition to the consistent demonstration that high KDPI kidneys (even 91%-100%) confer greater survival benefits to patients regarding the waiting list.

Early Graft Dysfunction Evaluation by Indocyanine Green Plasma Clearance Rate in the Immediate Postoperative Period After Liver Transplantation

BackgroundLiver transplantation (LT) has evolved to improve graft and patient survival. Early graft dysfunction (EGD) and primary nonfunction are an important cause of morbi-mortality. We had formulated the scientific hypothesis that the liver function can be evaluated by the indocyanine green (IG) after LT. The aim was to evaluate the EGD by plasma disappearance rate (PDR) of IG after LT. MethodProspective and observational clinical study, from July 2014 to June 2015. IG evaluation by pulse densitometry, Limon system. Degree analysis of ischemia and reperfusion injury in groups as follows: 1 (G0/G1/G2) and 2 (G3/G4). Donor risk index (DRI), Wagener and Olthoff criteria, and prognostic predictors were evaluated. All tests were performed with bidirectional α of 0.05 and a confidence interval of 95% and support by IBM SPSS 25. ResultsA total of 40 patients, mean age 53.3 ± 14.0 years and a majority of men and hepatitis C virus. PDR were more relevant with high degrees of ischemia and reperfusion injury grades G3/G4 (P = .030). The PDR related to the donor risk index showed positive significance at DRI >1.5 (P = .066). The retention rate of IG at 15 minutes demonstrated potential in assessing graft loss or death (P = .063). ConclusionEGD can be assessed by PDR with high degrees of ischemia and reperfusion injury (G3/G4) and with marginal donors (DRI >1.5). The retention rate of IG at 15 minutes demonstrated potential in assessing graft loss or death of the patient.

Indocyanine green dye clearance test: early graft (dys)-function and long-term mortality after liver transplant. Should we continue to use it? An observational study.

Early allograft dysfunction (EAD) can be a serious complication in the immediate postoperative period following liver transplantation. Our aim was to study the prognostic role of the indocyanine green plasma disappearance rate (ICG-PDR) in predicting early and late EAD and mortality at 3 and 12months and 5years after liver transplantation. ICG-PDR values were also assessed for association with the Donor Risk Index (DRI). 220 patients underwent orthotopic liver transplantation. In 77 patients, ICG-PDR was assessed on the 1st post-operative (PO) day. ICG, a water-soluble dye almost entirely excreted into the bile, was measured by spectrophotometry to evaluate graft (dys)-function. DRI was calculated in all patients. The primary study outcomes were the presence (or absence) of EAD after transplant and the results of mortality risk factor analysis. EAD occurred in 18 patients. 1st PO day ICG-PDR was significantly associated with EAD (p < 0.005). A threshold ICG-PDR value < 16%/min on the 1st PO day was also associated with patient probability to survive at 3 and 12months and 5years. The sensitivity and specificity of the AUC was good in predicting EAD, being 83% and 56%, respectively, for a 1st PO day ICG-PDR cut-off value < 16%/min. In this study, ICG-PDR on the 1st PO day following OLT can reliably predict EAD and survival at 3 and 12months and 5years. ICG-PDR should, therefore, be routinely performed on the 1st PO day following OLTx in all patients in light of its important prognostic role.