Chronic Kidney Disease After Liver Transplantation: Impact of Extended Criteria Grafts

Incidence and Risk Factors Associated With Chronic Kidney Disease After Liver Transplantation: A Review of a 20-Year Experience at a Single Center

BACKGROUND

Chronic kidney disease (CKD) is one of the major complications after liver transplantation (LT), with a significant impact on patient outcomes. This study aims to investigate the incidence and risk factors of CKD in LT recipients at Siriraj Hospital over the past 20 years.

METHODS

There were 366 adult patients undergoing LT at Siriraj Hospital between January 2002 and December 2021. After excluding patients with pretransplant CKD stages 4 to 5, simultaneous liver-kidney transplantation, and patients who died after LT within 90 days, we retrospectively reviewed a total of 288 patients. Univariable and multivariable binary logistic regression analyses were used to identify the risk factors of post-transplant CKD.

RESULTS

Of the 288 patients, 171 (59.4%) developed CKD after LT. The median time to develop CKD was 5.8 months (IQR, 3.8-15.3). Univariable and multivariable analyses revealed that age ≥55 years (odds ratio [OR] = 2.44; 95% CI, 1.34-4.42; P = .003), pretransplant kidney dysfunction defined as estimated glomerular filtration rate <60 mL/min/1.73 m2 (OR = 2.23; 95% CI, 1.16-4.27; P = .016), and postoperative acute kidney injury (OR = 3.06; 95% CI, 1.73-5.42; P < .001) were significantly associated with post-transplant CKD. Patients with preexisting kidney dysfunction who received delayed calcineurin inhibitor introduction without antibody induction protocol had a significantly lower incidence of post-transplant CKD (OR = 0.28; 95% CI, 0.11-0.70; P = .007).

CONCLUSIONS

Advanced age, pre-transplant kidney dysfunction, and postoperative acute kidney injury are risk factors for CKD after LT. Importantly, delayed calcineurin inhibitor introduction can protect patients with pretransplant kidney dysfunction from developing post-transplant CKD. These results may have important clinical implications in reducing the incidence of CKD after LT.

The effects of venovenous bypass use in liver transplantation with piggyback technique: a propensity score-weighted analysis

Venovenous bypass (VVB) use during liver transplantation (LT) is notably variable among the centres and it is actually restricted to surgically complex cases, severely unstable recipients or grafts from high-risk donors. Historically, VVB was associated with the classical LT with caval cross clamping, while not much is known about the safety of this technique applied to piggyback LT. This retrospective observational study evaluated the effects of VVB applied to piggyback LT on mortality, hospital outcomes, postoperative graft and other organ dysfunction. We retrospectively collected data about recipient status, surgical complexity and graft quality of all the piggyback LTs performed at the Transplant Unit of IRCCS Azienda Ospedaliero-Universitaria di Bologna, Italy, from January 2012 to December 2022. A propensity score (PS) was built taking into account the variables possibly associated with either VVB choice and the investigated outcomes with the average treatment overlap method. PS-weighted general linear models (GLMs) were developed to investigate the adjusted effect of VVB use on the selected outcomes. The final analysis included 874 LT cases, of whom 74 (8.5%) underwent VVB. The effective sample sizes after PS-weighting were 280.2 and 64.3 patients in the no-VVB and VVB groups, respectively. PS-weighted GLMs did not show any differences regarding hospital and graft-related outcomes. However, significantly higher odds ratios for serum creatinine > 2 mg/dL and AKIN stage 2 or 3 during the first 24 h after ICU admission together with a higher renal replacement therapy need during ICU stay were reported for VVB exposure in the weighted analyses. This study suggests similar mortality and length of stay but a higher risk for postoperative acute kidney injury in patients undergoing piggyback LT with VVB.

Complications in Post-Liver Transplant Patients

Liver transplantation (LT) is the treatment of choice for liver failure and selected cases of malignancies. Transplantation activity has increased over the years, and indications for LT have been widened, leading to organ shortage. To face this condition, a high selection of recipients with prioritizing systems and an enlargement of the donor pool were necessary. Several authors published their case series reporting the results obtained with the use of marginal donors, which seem to have progressively improved over the years. The introduction of in situ and ex situ machine perfusion, although still strongly debated, and better knowledge and treatment of the complications may have a role in achieving better results. With longer survival rates, a significant number of patients will suffer from long-term complications. An extensive review of the literature concerning short- and long-term outcomes is reported trying to highlight the most recent findings. The heterogeneity of the behaviors within the different centers is evident, leading to a difficult comparison of the results and making explicit the need to obtain more consent from experts.

COVID-19 in hospitalized solid organ transplant recipients in a nationwide registry study

OBJECTIVES

Underlying immunodeficiency has been associated with worse clinical presentation and increased mortality in patients with COVID-19. We evaluated the mortality of solid organ transplant (SOT) recipients (SOTR) hospitalized in Spain due to COVID-19.

METHODS

Nationwide, retrospective, observational analysis of all adults hospitalized because of COVID-19 in Spain during 2020. Stratification was made according to SOT status. The National Registry of Hospital Discharges was used, using the International Classification of Diseases, 10th revision coding list.

RESULTS

Of the 117,694 adults hospitalized during this period, 491 were SOTR: kidney 390 (79.4%), liver 59 (12%), lung 27 (5.5%), and heart 19 (3.9%). Overall, the mortality of SOTR was 13.8%. After adjustment for baseline characteristics, SOTR was not associated with higher mortality risk (odds ratio [OR] = 0.79, 95% confidence interval [CI] 0.60-1.03). However, lung transplantation was an independent factor related to mortality (OR = 3.26, 95% CI 1.33-7.43), while kidney, liver, and heart transplantation were not. Being a lung transplant recipient was the strongest prognostic factor in SOT patients (OR = 5.12, 95% CI 1.88-13.98).

CONCLUSION

This nationwide study supports that the COVID-19 mortality rate in SOTR in Spain during 2020 did not differ from the general population, except for lung transplant recipients, who presented worse outcomes. Efforts should be focused on the optimal management of lung transplant recipients with COVID-19.

Chronic Kidney Disease After Liver Transplantation

Chronic kidney disease among liver transplant recipients is common and associated with an increased mortality risk. Several risk factors and causes for the development of chronic kidney disease have been identified. They can be divided into perioperative factors, such as unresolved acute kidney injury; donor-related factors, such as the use of extended criteria liver allografts; and recipient-related factors, such as the use of calcineurin inhibitors and the presence of metabolic syndrome, diabetes, and obesity. There is a bimodal progression, more prominent during the initial post-transplant months, followed by a gradual but progressive decline over the subsequent years. Management strategies to prevent and treat chronic kidney disease in the general population can be reasonably applied to the liver transplant population and include addressing comorbidities such as hypertension and diabetes. Strategies to minimize or withdraw calcineurin inhibitors from the immunosuppressive regimen can slow progression of kidney dysfunction. Patients with advanced chronic kidney disease should be considered for kidney transplantation due to its survival advantage. Allocation policy in the United States confers safety-net allocation priority for liver transplant recipients who develop advanced chronic kidney disease within the first year of liver transplantation.

Good post-transplant outcomes using liver donors after circulatory death when applying strict selection criteria: A propensity-score matched-cohort study

INTRODUCTION AND OBJECTIVES

Outcomes of liver transplantation (LT) with donors after circulatory death (DCD) have been considered suboptimal due to higher rates of ischemic cholangiopathy, especially when the super-rapid recovery (SRR) technique is used. This study aimed to compare the incidence of complications between recipients receiving DCD vs those receiving donors after brain death (DBD) in a large-volume liver transplant centre.

METHODS

We performed a retrospective cohort study (LT from January 2015 to December 2018) comparing recipients who underwent a LT with DCD vs. a control group of LT with DBD, matched 1:1 without replacement by propensity score matching that included the following variables: LT indication, recipient sex and age, donor age and MELD score.

RESULTS

51 recipients with DCD-LT (29 SRR, 22 normothermic regional perfusion [NRP]) were matched with 51 DBD-LT recipients. Biliary complications were more frequent in DCD, 10% (n=5), all with SRR technique, vs 2% (n=1) in the DBD group, p=0.2. Two patients (4%) suffered primary graft non-function in the DCD group (1 SRR and 1 NRP) versus zero in the DBD group (p=0.49). Postoperative bleeding and reinterventions were also higher in the DCD group: 7 (13.7%) vs 1 (1.95%) and 8 (15.7%) vs 2 (3.9%) respectively (p=0.06 and 0.09). On the 1^st postoperative day AST/ALT peak was higher in DCD (p≤0001). The incidence of rejection, vascular complications, renal injury, hospital stay, and readmissions were similar in both groups. Cumulative 1-, 2-, 3- and 4-year graft and patient survival were also similar.

CONCLUSIONS

DCD donors are an adequate option to increase the donor pool in LT, achieving similar graft and patient survival rates to those achieved with DBD donors, especially when the NRP technique is used.

Machine Perfusion for Extended Criteria Donor Livers: What Challenges Remain?

Based on the renaissance of dynamic preservation techniques, extended criteria donor (ECD) livers reclaimed a valuable eligibility in the transplantable organ pool. Being more vulnerable to ischemia, ECD livers carry an increased risk of early allograft dysfunction, primary non-function and biliary complications and, hence, unveiled the limitations of static cold storage (SCS). There is growing evidence that dynamic preservation techniques—dissimilar to SCS—mitigate reperfusion injury by reconditioning organs prior transplantation and therefore represent a useful platform to assess viability. Yet, a debate is ongoing about the advantages and disadvantages of different perfusion strategies and their best possible applications for specific categories of marginal livers, including organs from donors after circulatory death (DCD) and brain death (DBD) with extended criteria, split livers and steatotic grafts. This review critically discusses the current clinical spectrum of livers from ECD donors together with the various challenges and posttransplant outcomes in the context of standard cold storage preservation. Based on this, the potential role of machine perfusion techniques is highlighted next. Finally, future perspectives focusing on how to achieve higher utilization rates of the available donor pool are highlighted.

Non-Renal Risk Factors for Chronic Kidney Disease in Liver Recipients with Functionally Intact Kidneys at 1 Month

Chronic kidney disease (CKD) is a critical complication of liver transplants, of which non-renal risk factors are not fully understood yet. This study aimed to reveal pre- and post-transplant risk factors for CKD (<60 mL/min/1.73 m2), examining liver recipients with functionally intact kidneys one month after grafting using nationwide cohort data. Baseline risk factors were analyzed with multivariable Cox regression analyses and post-transplant risk factors were investigated with the time-dependent Cox model and matched analyses of time-conditional propensity scores. Of the 2274 recipients with a one-month eGFR ≥ 60 mL/min/1.73 m2, 494 (22.3%) developed CKD during a mean follow-up of 36.6 ± 14.4 months. Age, female sex, lower body mass index, pre-transplant diabetes mellitus, and lower performance status emerged as baseline risk factors for CKD. Time-dependent Cox analyses revealed that recurrent hepatocellular carcinoma (HR = 1.93, 95% CI 1.06−3.53) and infection (HR = 1.44, 95% CI 1.12−1.60) were significant post-transplant risk factors for CKD. Patients who experienced one of those factors showed a significantly higher risk of subsequent CKD compared with the matched controls who lacked these features (p = 0.013 for recurrent hepatocellular carcinoma, and p = 0.003 for infection, respectively). This study clarifies pre- and post-transplant non-renal risk factors, which lead to renal impairment after LT independently from patients’ renal functional reserve.

Excess Risk of Major Adverse Cardiovascular and Kidney Events after Acute Kidney Injury following Living Donor Liver Transplantation

Acute kidney injury (AKI) is a well-known risk factor for major adverse kidney events (MAKE) and major adverse cardiovascular events (MACE) in nontransplant settings. However, the association between AKI after liver transplantation (LT) and MACE/MAKE is not established. A retrospective cohort analysis including 512 LT recipients was conducted. The incidence of post-LT AKI was 35.0% (n = 179). In total, 13 patients (2.5%) developed de novo coronary artery disease (CAD), 3 patients (0.6%) diagnosed with heart failure (HF), and 11 patients (2.1%) had stroke. The post-LT AKI group showed a higher incidence of CAD and HF than the no post-LT AKI group (4.5% versus 1.5%, p = 0.042; 1.7% versus 0%, p = 0.018; respectively), while there was no significant difference in the stroke events (2.8% versus 1.8%, p = 0.461). Through Cox regression analysis, history of cardiovascular disease (HR 6.51, 95% CI 2.43–17.46), post-LT AKI (HR 3.06, 95% CI 1.39–6.75), and pre-LT diabetes (HR 2.37, 95% CI 1.09–5.17) were identified as independent predictors of MACE; pre-LT chronic kidney disease (HR 9.54, 95% CI 3.49–26.10), pre-LT diabetes (HR 3.51, 95% CI 1.25–9.86), and post-LT AKI (HR 6.76, 95% CI 2.19–20.91) were risk factors for end-stage renal disease. Post-LT AKI is predictive for the development of MACE and MAKE.

[Kidney failure after liver transplantation]

One third of cirrhotic patients present impaired kidney function. It has multifactorial causes and has a harmful effect on patients' morbi-mortality before and after liver transplant. Kidney function does not improve in all patients after liver transplantation and liver-transplant recipients are at high risk of developing chronic kidney disease. Causes for renal dysfunction can be divided in three groups: preoperative, peroperative and postoperative factors. To date, there is no consensus for the modality of evaluation the risk for chronic kidney disease after liver transplantation, and for its prevention. In the present review, we describe the outcome of kidney function after liver transplantation, and the prognostic factors of chronic kidney disease to determine a risk stratification for each patient. Furthermore, we discuss therapeutic options to prevent kidney dysfunction in this setting, and highlight the indications of combined liver-kidney transplantation.

Effect of the response to preoperative treatment for hepatorenal syndrome on the outcome of recipients of living-donor liver transplantation

BACKGROUND

The effect of pretransplant hepatorenal syndrome (HRS) on the outcomes of living-donor liver transplantation (LDLT) recipients with special reference to the recovery of HRS before LDLT was investigated.

METHODS

The rate of HRS was 43.9% (125/285) among the cohort, and the subjects were divided into 3 groups: those without HRS (No-HRS group, n=160), those with HRS but recovered following pretransplant renal function restoration treatment (Responders group, n=55), and those with persistent HRS (Non-responders group, n=70).

RESULTS

While the 1-, 3-, and 5-year patient survival rates were comparable between those with and without HRS (89.6%, 84.7%, and 84.7% vs. 95.6%, 92.2%, and 87.5%), the cumulative incidence of the development of posttransplant chronic kidney disease (CKD) was significantly higher in those with HRS (p<0.001). In addition, there was a significant difference between Responders and Non-responders in the development of CKD (p=0.01). In the Cox regression model, Non-responders (p=0.032, HR 1.79 [95% C.I. 1.05-3.03]) and recipient age (p=0.014, HR 1.62 [95% C.I. 1.10-2.37]) were independent predictors for the development of CKD after LDLT.

CONCLUSION

LDLT is safe and effective for patients with HRS, and CKD progression could be reduced among those with HRS who responded to renal restoration treatment.

Textbook outcome among patients undergoing enhanced recovery after liver transplantation stratified by risk. A single-center retrospective observational cohort study

BACKGROUND & AIMS

Liver transplantation (LT) is one of the most complex surgical procedures. Enhanced recovery after surgery (ERAS) aims to reduce the risk of postoperative complications. When patients achieve all desirable outcomes after a procedure, they are considered to have experienced a textbook outcome (TO).

METHODS

Two cohorts of patients undergoing low (n = 101) or medium risk (n = 15) LT were identified. The remaining patients (n = 65) were grouped separately. The ERAS protocol included pre-, intra-, and post-operative steps. TO was defined as the absence of complications, prolonged length of hospital stays, readmission and mortality during the first 90 days.

RESULTS

One third of patients who underwent ERAS after LT experienced a TO. On multivariable analysis, age (OR, 1.05 [95% CI, 1.01-1.09]; P = .02), and having hepatocellular carcinoma (OR, 2.83 [95% CI, 1.37-6.03]; P = .005) were individually associated with a greater probability of achieving a TO. Belonging to the cohorts of medium risk or outside the selection criteria was associated with a lower probability of achieving a TO (OR, 0.46 [96% CI, 0.22-0.93]; P = .03). Patients less likely to experience TO required more hospital resources. Patients who achieved TO were more likely to remain free of chronic kidney disease (achieved TO, 83.8% [82.7-85.6]; failed TO, 67.9% [66.9-70.2]; P < .05). Tacrolimus dose and trough levels were similar.

CONCLUSIONS

A novel finding of our study is that short and medium-term kidney function is better preserved in patients who experience a TO. Better kidney function of patients who achieve TO is not due to lower tacrolimus dosage.

Prediction of chronic kidney disease after orthotopic liver transplantation: development and validation of a nomogram model

Background

We aimed to develop and validate a nomogram model for predicting CKD after orthotopic liver transplantation (OLT).

Methods

The retrospective data of 399 patients who underwent transplantation and were followed in our centre were collected. They were randomly assigned to the training set (n = 293) and validation set (n = 106). Multivariable Cox regression analysis was performed in the training set to identify predictors of CKD. According to the Cox regression analysis results, a nomogram model was developed and validated. The renal function of recipients was monitored, and the long-term survival prognosis was assessed.

Results

The incidence of CKD at 5 years after OLT was 25.6%. Cox regression analysis identified several predictors of post-OLT CKD, including recipient age at surgery (HR 1.036, 95% CI 1.006-1.068; p = 0.018), female sex (HR 2.867, 95% CI 1.709-4.810; p < 0.001), preoperative hypertension (HR 1.670, 95% CI 0.962-2.898; p = 0.068), preoperative eGFR (HR 0.996, 95% CI 0.991-1.001; p = 0.143), uric acid at 3 months (HR 1.002, 95% CI 1.001-1.004; p = 0.028), haemoglobin at 3 months (HR 0.970, 95% CI 0.956-0.983; p < 0.001), and average concentration of cyclosporine A at 3 months (HR 1.002, 95% CI 1.001-1.003; p < 0.001). According to these parameters, a nomogram model for predicting CKD after OLT was constructed and validated. The C-indices were 0.75 and 0.80 in the training and validation sets. The calibration curve of the nomogram showed that the CKD probabilities predicted by the nomogram agreed with the observed probabilities at 1, 3, and 5 years after OLT (p > 0.05). Renal function declined slowly year by year, and there were significant differences between patients divided by these predictors. Kaplan-Meier survival analysis showed that the survival prognosis of recipients decreased significantly with the progression of renal function.

Conclusions

With excellent predictive abilities, the nomogram may be a simple and reliable tool to identify patients at high risk for CKD and poor long-term prognosis after OLT.

Acute kidney injury and chronic kidney disease after liver transplant: A retrospective observational study

BACKGROUND AND RATIONALE

Chronic kidney disease remains an important risk factor for morbidity and mortality among LT recipients, but its exact incidence and risk factors are still unclear.

MATERIAL AND METHODS

We carried out a retrospective cohort study of consecutive adults who underwent liver transplant (January 2009-December 2018) and were followed (at least 6 months) at our institution. CKD was defined following the Kidney Disease: Improving Global Outcomes (KDIGO) 2012 Clinical Practice Guidelines. Long-term kidney function was classified into 4 groups: no CKD (eGFR, ≥60mL/min/1.73m²), mild CKD (eGFR, 30-59mL/min/1.73m²), severe CKD (eGFR, 15-29mL/min/1.73m²), and end-stage renal disease (ESRD).

RESULTS

We enrolled 410 patients followed for 53.2±32.6 months. 39 had CKD at baseline, and 95 developed de novo CKD over the observation period. There were 184 (44.9%) anti-HCV positive, 47 (11.5%) HBsAg positive, and 33 (8.1%) HBV/HDV positive recipients. Recipient risk factors for baseline CKD were advanced age (P=0.044), raised levels of serum uric acid (P<0.0001), and insulin dependent DM (P=0.0034). Early post-transplant AKI was common (n=95); logistic regression analysis found that baseline serum creatinine was an independent predictor of early post-LT AKI (P=0.0154). According to our Cox proportional hazards model, recipient risk factors for de novo CKD included aging (P<0.0001), early post-transplant AKI (P=0.007), and baseline serum creatinine (P=0.0002). At the end of follow-up, there were 116 LT recipients with CKD - 109 (93.9%) and 7 (6.1%) had stage 3 and advanced CKD, respectively. Only two of them are undergoing long-term dialysis.

CONCLUSION

The incidence of CKD was high in our cohort of LT recipients, but only a slight decline in kidney function over time was recorded. Prevention of post-transplant AKI will improve kidney function in the long run. We need more studies to analyze the function of kidneys among LT recipients over extended follow-ups and their impact on mortality.

Development and validation of a nomogram for predicting acute kidney injury after orthotopic liver transplantation

BACKGROUND

We aim to develop and validate a nomogram model for predicting severe acute kidney injury (AKI) after orthotopic liver transplantation (OLT).

METHODS

A total of 576 patients who received OLT in our center were enrolled. They were assigned to the development and validation cohort according to the time of inclusion. Univariable and multivariable logistic regression using the forward variable selection routine were applied to find risk factors for post-OLT severe AKI. Based on the results of multivariable analysis, a nomogram was developed and validated. Patients were followed up to assess the long-term mortality and development of chronic kidney disease (CKD).

RESULTS

Overall, 35.9% of patients were diagnosed with severe AKI. Multivariable logistic regression analysis revealed that recipients' BMI (OR 1.10, 95% CI 1.04-1.17, p = 0.012), hypertension (OR 2.32, 95% CI 1.22-4.45, p = 0.010), preoperative serum creatine (sCr) (OR 0.96, 95% CI 0.95-0.97, p < 0.001), and intraoperative fresh frozen plasm (FFP) transfusion (OR for each 1000 ml increase 1.34, 95% CI 1.03-1.75, p = 0.031) were independent risk factors for post-OLT severe AKI. They were all incorporated into the nomogram. The area under the ROC curve (AUC) was 0.73 (p < 0.05) and 0.81 (p < 0.05) in the development and validation cohort. The calibration curve demonstrated the predicted probabilities of severe AKI agreed with the observed probabilities (p > 0.05). Kaplan-Meier survival analysis showed that patients in the high-risk group stratified by the nomogram suffered significantly poorer long-term survival than the low-risk group (HR 1.92, p < 0.01). The cumulative risk of CKD was higher in the severe AKI group than no severe AKI group after competitive risk analysis (HR 1.48, p < 0.05).

CONCLUSIONS

With excellent predictive abilities, the nomogram may be a simple and reliable tool to identify patients at high risk for severe AKI and poor long-term prognosis after OLT.

Post-liver transplantation chronic kidney disease is associated with increased cardiovascular disease risk and poor survival

Chronic kidney disease (CKD) is common following liver transplantation (LT). We aimed to investigate the frequency, risk factors, and impact of CKD on cardiovascular disease (CVD), graft, and patient survival. We analyzed 752 patients who received LT at the University of Alberta. Development of CKD was defined as eGFR <60 ml/min for greater than 3 months, intrinsic renal disease or presence of end-stage renal disease requiring renal replacement therapy. 240 patients were female (32%), and mean age at LT was 53 ± 11 years. CKD was diagnosed in 448 (60%) patients. On multivariable analysis, age (OR 1.3; P = 0.01), female sex (OR 3.3; P < 0.001), baseline eGFR (OR 0.83; P < 0.001), MELD (OR 1.03; P = 0.01), de novo metabolic syndrome (OR 2.3; P = 0.001), and acute kidney injury (OR 3.5; P < 0.001) were associated with CKD. A higher tacrolimus concentration to dose ratio was protective for CKD (OR 0.69; P < 0.001). CKD was associated with post-transplant CVD (26% vs. 16% P < 0.001), reduced graft (HR 1.4; P = 0.02), and patient survival (HR 1.3; P = 0.03). CKD is a frequent complication following LT and is associated with an increased risk of CVD and reduced graft and patient survival.

Kidney Disease After Nonkidney Solid Organ Transplant

Nonkidney solid organ transplants (NKSOTs) are increasing in the United States with improving long-term allograft and patient survival. CKD is prevalent in patients with NKSOT and is associated with increased morbidity and mortality especially in those who progress to end-stage kidney disease. Calcineurin inhibitor nephrotoxicity is a main contributor to CKD after NKSOT, but other factors in the pretransplant, peritransplant, and post-transplant period can predispose to progressive kidney dysfunction. The management of CKD after NKSOT generally follows society guidelines for native kidney disease. Kidney-protective and calcineurin inhibitor-sparing immunosuppression has been explored in this population and warrants a discussion with transplant teams. Kidney transplantation in NKSOT recipients remains the kidney replacement therapy of choice for suitable candidates, as it provides a survival benefit over remaining on dialysis.

A meta-analysis of the cumulative incidence, risk factors, and clinical outcomes associated with chronic kidney disease after liver transplantation

Chronic kidney disease (CKD) remains a relatively common complication after liver transplantation (LT), and significantly impacts overall survival. We sought to assess the cumulative incidence, risk factors and mortality associated with post-LT CKD. CKD was defined as eGFR <60 ml/min/1.73 m² as estimated by the Modified Diet in Renal Disease (MDRD) formula. Single-arm meta-analysis was done to evaluate the cumulative incidence of CKD at 1-, 3-, and 5-year timepoints post-LT. Risk factors for CKD were evaluated using hazard ratios (HR). Twenty-one studies involving 44 383 patients were included. Cumulative incidence of stage 3-5 CKD was 31.44% (CI 0.182-0.447), 36.71% (CI 0.188-0.546), and 43.52% (CI 0.296-0.574) at 1, 3, and 5 years after LT, respectively. Stage 5 CKD cumulative incidence increased from 0.274% (CI 0.001-0.005) at 1 year to 2.06% (CI 0.009-0.045) at 5 years post-LT. Age, female sex, diabetes, and peri-operative acute kidney injury (AKI) were significant risk factors for CKD. Stage 4-5 CKD was associated with a decrease in overall survival (HR 3.23, 95% CI 1.74-5.98, P < 0.01). CKD after LT is relatively common, and is associated with significantly reduced overall survival. Identification of patients at high risk of developing CKD allows physicians to prophylactically use renal-sparing immunosuppression which may be crucial in achieving desirable clinical outcomes.

Kidney Failure after Liver Transplantation

One-third of patients with cirrhosis present kidney failure (AKI and CKD). It has multifactorial causes and a harmful effect on morbidity and mortality before and after liver transplantation. Kidney function does not improve in all patients after liver transplantation, and liver transplant recipients are at a high risk of developing chronic kidney disease. The causes of renal dysfunction can be divided into three groups: pre-operative, perioperative and post-operative factors. To date, there is no consensus on the modality to evaluate the risk of chronic kidney disease after liver transplantation, or for its prevention. In this narrative review, we describe the outcome of kidney function after liver transplantation, and the prognostic factors of chronic kidney disease in order to establish a risk categorization for each patient. Furthermore, we discuss therapeutic options to prevent kidney dysfunction in this context, and highlight the indications of combined liver–kidney transplantation.

Hepatocellular carcinoma in patients with renal dysfunction: Pathophysiology, prognosis, and treatment challenges

The population of patients with hepatocellular carcinoma (HCC) overlaps to a high degree with those for chronic kidney disease (CKD) and end-stage renal disease (ESRD). The degrees of renal dysfunction vary, from the various stages of CKD to dialysis-dependent ESRD, which often affects the prognosis and treatment choice of patients with HCC. In addition, renal dysfunction makes treatment more difficult and may negatively affect treatment outcomes. This study summarized the possible causes of the high comorbidity of HCC and renal dysfunction. The possible mechanisms of CKD causing HCC involve uremia itself, long-term dialysis status, immunosuppressive agents for postrenal transplant status, and miscellaneous factors such as hormone alterations and dysbiosis. The possible mechanisms of HCC affecting renal function include direct tumor invasion and hepatorenal syndrome. Finally, we categorized the risk factors that could lead to both HCC and CKD into four categories: Environmental toxins, viral hepatitis, metabolic syndrome, and vasoactive factors. Both CKD and ESRD have been reported to negatively affect HCC prognosis, but more research is warranted to confirm this. Furthermore, ESRD status itself ought not to prevent patients receiving aggressive treatments. This study then adopted the well-known Barcelona Clinic Liver Cancer guidelines as a framework to discuss the indicators for each stage of HCC treatment, treatment-related adverse renal effects, and concerns that are specific to patients with pre-existing renal dysfunction when undergoing aggressive treatments against CKD and ESRD. Such aggressive treatments include liver resection, simultaneous liver kidney transplantation, radiofrequency ablation, and transarterial chemoembolization. Finally, focusing on patients unable to receive active treatment, this study compiled information on the latest systemic pharmacological therapies, including targeted and immunotherapeutic drugs. Based on available clinical studies and Food and Drug Administration labels, this study details the drug indications, side effects, and dose adjustments for patients with renal dysfunction. It also provides a comprehensive review of information on HCC patients with renal dysfunction from disease onset to treatment.

Acute kidney injury and chronic kidney disease after liver transplant: A retrospective observational study

BACKGROUND AND RATIONALE

Chronic kidney disease remains an important risk factor for morbidity and mortality among LT recipients, but its exact incidence and risk factors are still unclear.

MATERIAL AND METHODS

We carried out a retrospective cohort study of consecutive adults who underwent liver transplant (January 2009-December 2018) and were followed (at least 6 months) at our institution. CKD was defined following the Kidney Disease: Improving Global Outcomes (KDIGO) 2012 Clinical Practice Guidelines. Long-term kidney function was classified into 4 groups: no CKD (eGFR, ≥60mL/min/1.73m2), mild CKD (eGFR, 30-59mL/min/1.73m2), severe CKD (eGFR, 15-29mL/min/1.73m2), and end-stage renal disease (ESRD).

RESULTS

We enrolled 410 patients followed for 53.2±32.6 months. 39 had CKD at baseline, and 95 developed de novo CKD over the observation period. There were 184 (44.9%) anti-HCV positive, 47 (11.5%) HBsAg positive, and 33 (8.1%) HBV/HDV positive recipients. Recipient risk factors for baseline CKD were advanced age (P=0.044), raised levels of serum uric acid (P<0.0001), and insulin dependent DM (P=0.0034). Early post-transplant AKI was common (n=95); logistic regression analysis found that baseline serum creatinine was an independent predictor of early post-LT AKI (P=0.0154). According to our Cox proportional hazards model, recipient risk factors for de novo CKD included aging (P<0.0001), early post-transplant AKI (P=0.007), and baseline serum creatinine (P=0.0002). At the end of follow-up, there were 116 LT recipients with CKD - 109 (93.9%) and 7 (6.1%) had stage 3 and advanced CKD, respectively. Only two of them are undergoing long-term dialysis.

CONCLUSION

The incidence of CKD was high in our cohort of LT recipients, but only a slight decline in kidney function over time was recorded. Prevention of post-transplant AKI will improve kidney function in the long run. We need more studies to analyze the function of kidneys among LT recipients over extended follow-ups and their impact on mortality.

Donor Gamma-Glutamyl Transferase Is Associated With Liver Allograft Discard and Failure

INTRODUCTION

The disparity between the number of individuals on the wait list and available liver allografts creates the need for a system that maximizes donor liver utilization and predicts graft failure.

RESEARCH QUESTION

This study aimed to determine the relationship between donor Gamma-Glutamyl Transferase (GGT), liver discard, and graft failure.

DESIGN

Through multivariate analysis from 53 966 deceased liver donors, we adjusted for donor clinical and demographic characteristics and compared donor GGT with allograft discard. We compared donor GGT ranges with graft failure and analyzed data from 47 269 liver recipients.

RESULTS

After adjusting for other factors, donor GGT was significantly associated with liver discard, with GGT over 200 U/L being most significant (OR 2.74, CI 2.51-2.99). Donor GGT under 20 U/L was also found to be a protective factor for post-transplant graft failure (HR 0.91, CI 0.83 - 1.00).

CONCLUSION

Going forward, GGT should be included among other characteristics associated with allograft discard considered during the procurement process.

Kidney Function After Liver Transplantation in a Single Center

Background

Renal dysfunction in the peri-transplant period appears to complicate both short- and long-term outcome of liver transplantation (LT). The aim of this study was to analyze the impact of selected clinical features in the peri-liver transplant period, as well calcineurin inhibitor, particularly tacrolimus given after LT, on kidney function in a single liver transplant center’s experience.

Material/Methods

A total 125 consecutive liver-grafted individuals (82 M, 43 F), mean age 50±13 y (with alcohol-related liver disease in 48 (38%) patients) were included into the study. Their clinical data were collected in the database until 46 months of follow-up, and the Python packages Pandas (version 0.22.0) and scikit-learn (version 0.21.3) were used for data analysis.

Results

More advanced liver disease as judged by Child-Pugh class and MELD score differed significantly patients with preserved (serum creatinine SCr <1.5 mg/dL) and impaired (SCr ≥1.5 mg/dL) kidney function before LT. Older age and higher SCr pre-LT were associated with higher levels of SCr after LT in 2 time-points. SCr before LT was correlated with delta SCr for the highest and last recorded value (P<0.0001). Higher amounts of transfused colloids during surgery were associated with increased delta SCr for the highest value (P=0.019) after grafting in logistic regression analysis. There were no associations between SCr after LT and duration of anhepatic phase, urine output ≤100 mL/h, or post-reperfusion syndrome during transplantation (all P>0.05). There were no associations between SCr after LT and tacrolimus trough levels in analyses of correlations and linear regression analyses (all P>0.05).

Conclusions

We found that pretransplant serum creatinine was the only factor affecting kidney function after LT in our liver transplant center. The restricted fluid policy was safe and effective in terms of long-term renal function. The role of kidney-saving immunosuppressive protocols in preserving renal function long-term after LT was also confirmed.

Different Severity of Clinical Outcomes Between the 2 Subgroups of Stage 1 Acute Kidney Injury After Liver Transplantation

BACKGROUND

Although the Kidney Disease: Improving Global Outcomes (KDIGO) criteria is used to define acute kidney injury (AKI) after liver transplantation, the criteria was criticized for including 2 heterogeneous groups of different serum creatinine (sCr) criteria together in AKI stage 1. We investigated whether there are significant differences in clinical outcomes between 2 subgroups of patients within AKI stage 1.

METHODS

A total of 1440 cases were reviewed. The AKI stage 1 (n = 443) were divided into 2 subgroups based on changes in sCr level (stage 1a: ≥0.3 mg/dL of absolute sCr increase, n = 251; stage 1b: ≥50% relative sCr increase, n = 192). Propensity score analysis was performed between stage 1a and 1b groups, yielding 157 matched pairs. We compared the length of hospital stay, early allograft dysfunction, and 5-year all-cause mortality between these subgroups after matching. Kaplan-Meier analyses were performed to compare the graft or overall survival between the subgroups after matching. Sensitivity analysis for Acute Kidney Injury Network (AKIN) criteria was performed.

RESULTS

Length of hospital stay and 5-year all-cause mortality was significantly worse in patients with stage 1b compared to stage 1a after matching. Five-year graft or patient survival was significantly worse in patients with stage 1b compared to stage 1a after matching (Log-rank test P = 0.022 and P = 0.027, respectively). These results were the same regarding AKIN criteria.

CONCLUSIONS

The KDIGO criteria for AKI stage 1 could be further divided into 2 substages with different severity of clinical outcomes. This modified criteria could give additional prognostic information in patients undergoing liver transplantation.

Incidence of chronic kidney disease after orthotopic liver transplantation in a Chinese cohort

BACKGROUND

Kidney dysfunction frequently occurred after orthotopic liver transplantation (OLT). Chronic renal disease (CKD) is a complicated problem and is associated with increased mortality. The aim of this study is to find the risk factors for the incidence of CKD at 1 year after OLT in China.

METHODS

From January 2017 to December 2017, we retrospectively assessed 280 recipients in our single center. Chronic renal failure was defined as estimated glomerular filtration rate (eGFR) < 60 mL/min/1.73 m² for 3 months, regardless of the presence or absence of structural kidney damage. Cox proportional hazard model was used to identify the factors to the incidence of CKD after liver transplantations. Kaplan-Meier plots with log-rank test were presented to evaluate patient survival time in those with and without CKD.

RESULTS

With a median follow-up of 17.4 months, 48 patients developed CKD after liver transplantations, representing 17.1% of the cohort. The cox-regression model showed that recipients age (HR = 1.097, P < 0.01), AKI (HR = 1.542, P < 0.01) and MELD score (HR = 1.077, P < 0.01) were significantly associated with the development of post-transplant CKD at 1 year. Recipient survival at 1 year was significantly worse in recipients with CKD compared to those without CKD (P < 0.01) after adjustment by age and gender.

CONCLUSION

Our findings suggested that age, AKI and MELD score were associated with the incidence of CKD 1 year after OLT in a Chinese cohort. Recipients with CKD were associated with worse survival.