Evolving frequency and outcomes of simultaneous liver kidney transplants based on liver disease etiology. Transplantation. 2014;98:216-221. [PMID: 24621538 DOI: 10.1097/tp.0000000000000048]

Simultaneous liver-kidney transplantation: future perspective

BACKGROUND

The aims of this narrative review were (i) to describe the current indications of SLKT, (ii) to report evolution of SLKT activity, (iii) to report the outcomes of SLKT, (iv) to explain the immune-protective effect of liver transplant on kidney transplant, (v) to explain the interest of delay kidney transplantation, using hypothermic machine perfusion (HMP), (vi) to report kidney after liver transplantation (KALT) indications and (vii) to describe the value of the increase in the use of extended criteria donors (ECD) and particular controlled donation after circulatory death (cDCD) transplant, thanks to the development of new organ preservation strategies.

METHOD

Electronic databases were screened using the keywords "Simultaneous", "Combined", "kidney transplantation" and "liver transplantation". The methodological and clinical heterogeneity of the included studies meant that meta-analysis was inappropriate.

RESULTS

 A total of 1,917 publications were identified in the literature search. Two reviewers screened all study abstracts independently and 1,107 of these were excluded. Thus, a total of 79 full text articles were assessed for eligibility. Of these, 21 were excluded. In total, 58 studies were included in this systematic review.

CONCLUSIONS

 Simultaneous liver-kidney transplantation has made a significant contribution for patients with dual-organ disease. The optimization of indication and selection of SLKT patients will reduce futile transplantation. Moreover, increasing the use of transplants from extended criteria donors, in particular cDCD, should be encouraged, thanks to the development of new modalities of organ preservation.

Waitlist and post-transplant outcomes among candidates listed for liver transplant: Liver alone versus simultaneous liver kidney listings

BACKGROUND

Data comparing waitlist and post-transplant outcomes of liver transplantation (LT) alone (LTA) versus simultaneous liver kidney (SLK) listings are limited.

AIM

To examine 90-days waitlist and 1-year post-transplant outcomes of LT listings since Organ Procurement Transplant Network (OPTN) policy for SLK, who had cirrhosis with eGFR <30 mL/min or on dialysis at listing.

METHODS

Adults (08/2017-03/2021) with first LT listing (2628 SLK) were stratified on renal function from listing: acute kidney injury (AKI): rise of serum creatinine by ≥0.3 mg/dL or <42 days hemodialysis; chronic kidney disease (CKD): eGFR <60 mL/min for ≥90 days or ≥42 days hemodialysis.

RESULTS

Among 7094 adults analyzed, 90-days competing cumulative waitlist mortality was 18.2% in LTA + CKD (n = 37), 15.3% in LTA + AKI (n = 3337), 15% in SLK + AKI (n = 2070), and 11% in SLK + CKD (n = 403), p < 0.001. On fine and gray model, compared to SLK + CKD, LTA + AKI had 1.4-fold waitlist mortality. On a median post-transplant follow up of 1 year, patient survival was similar comparing LTA versus SLK for AKI (89% each, p = 0.83), for CKD (93 vs. 86%, p = 0.55), but lower in recipients listed for SLK with no AKI or CKD (93 vs. 88%, p = 0.02), adjusted hazard ratio (95% CI) of 0.7 (0.4-1.2). Among 1024 LTA recipients without AKI or CKD from listing, 117 were listed for SLK, and their 1-year survival was poorer compared to LT alone listings (79 vs. 95%, p < 0.002, adjusted HR 3.6 (1.3-10.3); p = 0.015).

CONCLUSIONS

Among candidates with renal dysfunction at listing for LT, those listed for LT alone should receive transplant promptly to optimise waitlist outcomes. Those listed for SLK should wait to receive both organs to optimise post-transplant outcomes.

Nonalcoholic Fatty Liver Disease Predicts Acute Kidney Injury Readmission in Heart Failure Hospitalizations: A Nationwide Analysis

Nonalcoholic fatty liver disease (NAFLD) has been associated with the progression of chronic kidney disease. However, limited data is available on its impact on acute kidney injury (AKI) in heart failure(HF) patients. All primary adult HF admissions from the national readmission database of 2016-2019 were identified. Admissions from July to December of each year were excluded to allow 6 months of follow-up. Patients were stratified according to the presence of NAFLD. Complex multivariate cox regression was used to adjust for confounders and calculate the adjusted hazard ratio. A total of 420,893 weighted patients admitted with HF were included in our cohort, of whom 780 had a secondary diagnosis of NAFLD. Patients with NAFLD were younger, more likely to be female, and had higher rates of obesity and diabetes mellitus. Both groups had similar rates of chronic kidney disease irrespective of the stage. NAFLD was associated with an increased risk of 6-month readmission with AKI (26.8% vs 16.6%, adjusted hazard ratio:1.44, 95% CI [1.14-1.82], P = 0.003). The mean time to AKI readmission was 150 ± 44 days. NAFLD was associated with a shorter mean time to readmission (145 ± 45 vs 155 ± 42 days, β =  -10 days, P = 0.044). Our study from a national database suggests that NAFLD is an independent predictor of 6-months readmission with AKI in patients admitted with HF. Further research is warranted to validate these findings.

Essentials of Liver Transplantation in the Setting of Acute Kidney Injury and Chronic Kidney Disease

Kidney dysfunction is common among liver transplant candidates with decompensated cirrhosis and has a major impact on pre- and post-liver transplant survival. Updated definitions of acute kidney injury and criteria for the diagnosis of hepatorenal syndrome allow for early recognition and intervention, including early initiation of vasoconstrictor therapy for hepatorenal syndrome. The rise of the metabolic syndrome and nonalcoholic fatty liver disease as a cause of cirrhosis has coincided with an increase in intrinsic chronic kidney disease recognized in transplant candidates and recipients. Ultimately, the ability to accurately assess kidney function and associated risk is essential to decision-making in the context of transplantation, including selection of candidates for simultaneous liver and kidney transplantation.

Safety and efficacy of dyslipidemia treatment in NAFLD patients: a meta-analysis of randomized controlled trials

INTRODUCTION AND OBJECTIVES

Practicing physicians often hesitate to use statins and/or other lipid-lowering therapies in NAFLD due to concern for hepatotoxicity. The aim of this study is to examine the safety of lipid lowering therapies in NAFLD patients.

MATERIALS AND METHODS

Data from randomized control trials (RCT) among NAFLD patients were pooled to examine the effect of lipid-lowering therapies on liver chemistry, lipid profile, and liver histology. Results are reported as the mean difference of the change (pretreatment-posttreatment) between the treatment and control group.

RESULTS

A total of 21 placebo-controlled RCT on 1900 patients (304 receiving statins, 520 other lipid-lowering therapies, and 61 combinations) were treated for 26 weeks [Interquartile range (IQR): 17.5-52 weeks]. Pooled data showed an improved lipid profile without any worsening of ALT, AST, total bilirubin, or alkaline phosphatase at the end of the treatment period. NAFLD activity score improved with other lipid-lowering agents but not with statins. There was no change in individual components of NAFLD activity score or fibrosis stage.

CONCLUSION

This meta-analysis of randomized controlled trials examining statins and/or other lipid-lowering therapies in NAFLD patients showed no evidence of worsening liver chemistry. Studies with longer use of lipid-lowering therapies are suggested to examine the benefit of liver histology among patients with NAFLD.

Long-term outcomes of crossmatch positive simultaneous liver-kidney transplantations in the United States

The long-term outcomes of positive crossmatch (+XM) simultaneous liver-kidney (SLK) transplantations are conflicting. We examined the association between crossmatch status and SLK outcomes in recipients discharged on tacrolimus and mycophenolate with or without steroids. We analyzed the Scientific Registry of Transplant Recipients for all primary SLK recipients between 2003 and 2020 with available crossmatch and induction data. We grouped recipients according to the crossmatch status: negative crossmatch (-XM; n = 3040) and +XM (n = 407). Kaplan-Meier curves were generated to examine recipient, death-censored liver, and death-censored kidney survival by crossmatch status. Cox proportional hazard models were used to investigate the association between crossmatch status and outcomes of interest with follow-up censored at 10 years. Models were adjusted for recipient age, sex, diabetes mellitus, Model for End-Stage Liver Disease score, duration on the liver waiting list, induction immunosuppression, steroid maintenance, hepatitis C infection, donor age and sex, local vs. shared organ, cold ischemia time, and previous liver transplantation status. In the univariable analysis, crossmatch status was not associated with recipient survival (log-rank p = 0.63), death-censored liver graft survival (log-rank p = 0.05), or death-censored kidney graft survival (log-rank p = 0.11). Compared with -XM, +XM recipients had a similar 1-year liver rejection rate, but higher kidney rejection rate (4.6% vs. 8.9%, p = 0.002). In the multivariable models, +XM status was not associated with deleterious long-term recipient, liver, or kidney grafts survival. -XM and +XM SLK transplantations have comparable long-term recipient, liver graft, and kidney survival with a slightly increased risk of early kidney allograft rejection in the +XM group. Crossmatch positivity in SLK transplantations should not influence the decision to use organs from a specific donor.

The Burden of Nonalcoholic Steatohepatitis: A Systematic Review of Epidemiology Studies

Background and Aims

Nonalcoholic steatohepatitis (NASH) is associated with increased mortality and risk of complications but is often asymptomatic and under-recognized. A systematic review of NASH epidemiology was conducted to provide information on the burden of NASH and highlight important evidence gaps for future research.

Methods

Medline, EMBASE, and Cochrane Library databases were searched for English-language publications published from 2010 to January 2022 that reported on natural history, risk factors, comorbidities, and complications of a NASH population or subpopulation.

Results

Overall, 173 publications were included. NASH was shown to have a variable disease course and high prevalence of comorbid disease. Although many patients progressed to cirrhosis and end-stage liver disease, disease regression or resolution was reported in up to half of patients in some studies. Reported risk factors for disease progression or resolution included levels of (or changes in) serum fibrosis markers, liver enzymes, and platelets. The presence of NASH increased the risk of liver cirrhosis and other serious diseases such as hepatocellular carcinoma, colorectal cancer, chronic kidney disease, and cardiovascular disease. In 2017, NASH was responsible for ∼118,000 cirrhosis deaths globally, and an increasing proportion of patients are receiving liver transplantation for NASH in Europe and the United States. Consolidation of data was hampered by heterogeneity across the studies in terms of patient populations, follow-up time, and outcomes measured.

Conclusion

NASH is associated with significant morbidity and mortality, an increased risk of comorbidities, and imposes an increasing burden among liver transplantation recipients. Longer studies with harmonized study criteria are required to better understand the impact of NASH on patient outcomes.

Impact of medical eligibility criteria and OPTN policy on simultaneous liver kidney allocation and utilization

BACKGROUND

Organ Procurement and Transplantation Network (OPTN) implemented medical eligibility and safety-net policy on 8/10/17 to optimize simultaneous liver-kidney (SLK) utilization. We examined impact of this policy on SLK listings and number of kidneys used within 1-yr. of receiving liver transplantation (LT) alone.

METHODS AND RESULTS

OPTN database (08/10/14-06/12/20) on adults (N = 66 709) without previous transplant stratified candidates to listings for SLK or LT alone with pre-LT renal dysfunction at listing (eGFR < 30 mL/min or on dialysis). Outcomes were compared for pre (08/10/14-08/09/17) vs. post (08/10/17-06/12/20) policy era. SLK listings decreased in post vs. pre policy era (8.7% vs. 9.6%; P < .001), with 22% reduced odds of SLK listing in the postpolicy era, with a decrease in all OPTN regions except regions 6 and 8, which showed an increase. Among LT-alone recipients with pre-LT renal dysfunction (N = 3272), cumulative 1-year probability was higher in post vs. prepolicy period for dialysis (5.6% vs. 2.3%; P < .0001), KT listing (11.4% vs. 2.0%; P < .0001), and KT (3.7% vs. .25%; P < .0001). Sixty-seven (2.4%) kidneys were saved in post policy era, with 18.1%, 16.6%, 4.3%, and 2.9% saving from regions 7, 2, 11, and 1, respectively.

CONCLUSION

Medical eligibility and safety-net OPTN policy resulted in decreased SLK use and improved access to LT alone among those with pre-LT renal dysfunction. Although decreased in postpolicy era, regional variation of SLK listings remains. In spite of increased use of KT within 1-year of receiving LT alone under safety net, less number of kidneys were used without impact on patient survival in postpolicy era.

The association between NAFLD and risk of chronic kidney disease: a cross-sectional study

Objective:

The aim of this study was to evaluate the association between nonalcoholic fatty liver disease (NAFLD) and NAFLD with different comorbidities and risk of chronic kidney disease (CKD) and abnormal albuminuria.

Materials and Methods:

A total of 3872 Chinese individuals excluding those with hepatitis B or C infection and absence of alcohol abuse were included in the study. NAFLD was diagnosed by abdominal ultrasonography. The liver fibrosis was assessed by NAFLD fibrosis score (NFS) and fibrosis-4 index (FIB-4). CKD was defined as an estimated glomerular filtration rate (eGFR) < 60 ml/min/1.73 m² and/or abnormal albuminuria (urinary albumin-to-creatinine ratio ⩾ 3 mg/mmol). The logistic regression analysis was performed to examine the association between NAFLD and NAFLD with different comorbidities and risk of CKD.

Results:

The prevalence of CKD and abnormal albuminuria was higher in individuals with NAFLD than in those without NAFLD (15.8% vs 11.9%, p < 0.001; 14.8% vs 11.0%, p < 0.001). Logistic regression analysis demonstrated that NAFLD was risk factor of CKD. Notably, after adjustment for sex, age, and DM, NAFLD was associated with 1.31-fold higher risk of prevalent CKD ⩾ 1 (p < 0.05). NAFLD individuals with elder age, DM, obesity, hypertension, MetS, and advanced liver fibrosis had higher risks of both prevalent CKD and abnormal albuminuria than those without comorbidities.

Conclusions:

NAFLD and NAFLD with traditional comorbidities are strongly associated with risk of prevalence of CKD and abnormal albuminuria. Patients with NAFLD especially those with coexisting comorbidities were recommended to carefully access the development of CKD.

Current State of Multiorgan Transplantation and Implications for Future Practice and Policy

The incidence of kidney dysfunction has increased in liver transplant and heart transplant candidates, reflecting a changing patient population and allocation policies that prioritize the most urgent candidates. A higher burden of pretransplant kidney dysfunction has resulted in a substantial rise in the utilization of multiorgan transplantation (MOT). Owing to a shortage of available deceased donor kidneys, the increased use of MOT has the potential to disadvantage kidney-alone transplant candidates, as current allocation policies generally provide priority for MOT candidates above all kidney-alone transplant candidates. In this review, the implications of kidney disease in liver transplant and heart transplant candidates is reviewed, and current policies used to allocate organs are discussed. Important ethical considerations pertaining to MOT allocation are examined, and future policy modifications that may improve both equity and utility in MOT policy are considered.

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.

Non-alcoholic fatty liver and chronic kidney disease: Retrospect, introspect, and prospect

With the growing prevalence of obesity and diabetes in the United States and across the world, a rise in the overall incidence and prevalence of non-alcoholic fatty liver disease (NAFLD) is expected. The risk factors for NAFLD are also associated with the development of chronic kidney disease (CKD). We review the epidemiology, risk factors, genetics, implications of gut dysbiosis, and specific pathogenic mechanisms linking NAFLD to CKD. Mechanisms such as ectopic lipid accumulation, cellular signaling abnormalities, and the interplay between fructose consumption and uric acid accumulation have led to the emergence of potential therapeutic implications for this patient population. Transplant evaluation in the setting of both NAFLD and CKD is also reviewed. Potential strategies for surveillance and management include the monitoring of comorbidities, the use of non-invasive fibrosis scoring systems, and the measurement of laboratory markers. Lastly, we discuss the management of patients with NAFLD and CKD, from preventative measures to experimental interventions.

Chronic renal dysfunction in cirrhosis: A new frontier in hepatology

Chronic kidney disease (CKD) in patients with liver cirrhosis has become a new frontier in hepatology. In recent years, a sharp increase in the diagnosis of CKD has been observed among patients with cirrhosis. The rising prevalence of risk factors, such as diabetes, hypertension and nonalcoholic fatty liver disease, appears to have contributed significantly to the high prevalence of CKD. Moreover, the diagnosis of CKD in cirrhosis is now based on a reduction in the estimated glomerular filtration rate of < 60 mL/min over more than 3 mo. This definition has resulted in a better differentiation of CKD from acute kidney injury (AKI), leading to its greater recognition. It has also been noted that a significant proportion of AKI transforms into CKD in patients with decompensated cirrhosis. CKD in cirrhosis can be structural CKD due to kidney injury or functional CKD secondary to circulatory and neurohormonal imbalances. The available literature on combined cirrhosis-CKD is extremely limited, as most attempts to assess renal dysfunction in cirrhosis have so far concentrated on AKI. Due to problems related to glomerular filtration rate estimation in cirrhosis, the absence of reliable biomarkers of CKD and technical difficulties in performing renal biopsy in advanced cirrhosis, CKD in cirrhosis can present many challenges for clinicians. With combined hepatorenal dysfunctions, fluid mobilization becomes problematic, and there may be difficulties with drug tolerance, hemodialysis and decision-making regarding the need for liver vs simultaneous liver and kidney transplantation. This paper offers a thorough overview of the increasingly known CKD in patients with cirrhosis, with clinical consequences and difficulties occurring in the diagnosis and treatment of such patients.

Metabolic associated fatty liver disease: Addressing a new era in liver transplantation

Metabolic associated fatty liver disease (MAFLD), previously termed non-alcoholic fatty liver disease, is the leading global cause of liver disease and is fast becoming the most common indication for liver transplantation. The recent change in nomenclature to MAFLD refocuses the conceptualisation of this disease entity to its metabolic underpinnings and may help to spur a paradigm shift in the approach to its management, including in the setting of liver transplantation. Patients with MAFLD present significant challenges in the pre-, peri- and post-transplant settings, largely due to the presence of medical comorbidities that include obesity, metabolic syndrome and cardiovascular risk factors. As the community prevalence of MAFLD increases concurrently with the obesity epidemic, donor liver steatosis is also a current and future concern. This review outlines current epidemiology, nomenclature, management issues and outcomes of liver transplantation in patients with MAFLD.

Assessing the Time-Dependent Impact of Performance Status on Outcomes After Liver Transplantation

BACKGROUND AND AIMS

Identifying how the prognostic impact of performance status (PS) differs according to indication, era, and time period ("epoch") after liver transplantation (LT) could have implications for selection and treatment of patients on the waitlist. We used national data from the United Kingdom and Ireland to assess impact of PS on mortality separately for HCC and non-HCC recipients.

APPROACH AND RESULTS

We assessed pre-LT PS using the 5-point modified Eastern Cooperative Oncology Group scale and used Cox regression methods to estimate hazard ratios (HRs) that compared posttransplantation mortality in different epochs of follow-up (0-90 days and 90 days to 1 year) and in different eras of transplantation (1995-2005 and 2006-2016). 2107 HCC and 10,693 non-HCC patients were included. One-year survival decreased with worsening PS in non-HCC recipients where 1-year survival was 91.9% (95% confidence interval [CI], 88.3-94.4) in those able to carry out normal activity (PS1) compared to 78.7% (95% CI, 76.7-80.5) in those completely reliant on care (PS5). For HCC patients, these estimates were 89.9% (95% CI, 85.4-93.2) and 83.1% (95% CI, 61.0-93.3), respectively. Reduction in survival in non-HCC patients with poorer PS was in the first 90 days after transplant, with no major effect observed between 90 days and 1 year. Adjustment for donor and recipient characteristics did not change the findings. Comparing era, post-LT mortality improved for HCC (adjusted HR, 0.55; 95% CI, 0.40-0.74) and non-HCC recipients (0.48; 95% CI, 0.42-0.55), but this did not differ according to PS score (P = 0.39 and 0.61, respectively).

CONCLUSIONS

Impact on mortality of the recipient's pretransplant PS is principally limited to the first 3 months after LT. Over time, mortality has improved for both HCC and non-HCC recipients and across the full range of PS.

Clinical considerations in the management of non-alcoholic steatohepatitis cirrhosis pre- and post-transplant: A multi-system challenge

Non-alcoholic steatohepatitis (NASH) is the most common chronic liver disease worldwide, and the fastest growing indication for liver transplantation in the United States. NASH is now the leading etiology for liver transplantation in women, the second leading indication for men, and the most common cause amongst recipients aged 65 years and older. Patients with end-stage liver disease related to NASH represent a unique and challenging patient population due the high incidence of associated comorbid diseases, including obesity, type 2 diabetes (T2D), and hypertension. These challenges manifest in the pre-liver transplantation period with increased waitlist times and waitlist mortality. Furthermore, these patients carry considerable risk of morbidity and mortality both before after liver transplantation, with high rates of T2D, cardiovascular disease, chronic kidney disease, poor nutrition, and disease recurrence. Successful transplantation for these patients requires identification and management of their comorbidities in the face of liver failure. Multidisciplinary evaluations include a thorough pre-transplant workup with a complete cardiac evaluation, control of diabetes, nutritional support, and even, potentially, consultation with a bariatric surgeon. This article provides a comprehensive review of the conditions and challenges facing patients with NASH cirrhosis undergoing liver transplantation and provides recommendations for evaluation and management to optimize them before liver transplantation to produce successful outcomes.

Common Drug Pipelines for the Treatment of Diabetic Nephropathy and Hepatopathy: Can We Kill Two Birds with One Stone?

Type 2 diabetes (T2D) is associated with diabetic nephropathy as well as nonalcoholic steatohepatitis (NASH), which can be called "diabetic hepatopathy or diabetic liver disease". NASH, a severe form of nonalcoholic fatty disease (NAFLD), can sometimes progress to cirrhosis, hepatocellular carcinoma and hepatic failure. T2D patients are at higher risk for liver-related mortality compared with the nondiabetic population. NAFLD is closely associated with chronic kidney disease (CKD) or diabetic nephropathy according to cross-sectional and longitudinal studies. Simultaneous kidney liver transplantation (SKLT) is dramatically increasing in the United States, because NASH-related cirrhosis often complicates end-stage renal disease. Growing evidence suggests that NAFLD and CKD share common pathogenetic mechanisms and potential therapeutic targets. Glucagon-like peptide 1 (GLP-1) receptor agonists and sodium-glucose cotransporter 2 (SGLT2) inhibitors are expected to ameliorate NASH and diabetic nephropathy/CKD. There are no approved therapies for NASH, but a variety of drug pipelines are now under development. Several agents of them can also ameliorate diabetic nephropathy/CKD, including peroxisome proliferator-activated receptors agonists, apoptosis signaling kinase 1 inhibitor, nuclear factor-erythroid-2-related factor 2 activator, C-C chemokine receptor types 2/5 antagonist and nonsteroidal mineral corticoid receptor antagonist. This review focuses on common drug pipelines in the treatment of diabetic nephropathy and hepatopathy.

Glomerular Hyperfiltration Is Associated with Liver Disease Severity in Children with Nonalcoholic Fatty Liver Disease

OBJECTIVES

To determine the prevalence of renal impairment in a large cohort of youths with histologically confirmed nonalcoholic fatty liver disease (NAFLD), and to determine its association with liver disease severity.

STUDY DESIGN

Clinical, laboratory, and histology data were collected retrospectively in a pediatric cohort with biopsy-confirmed NAFLD at a tertiary care center between 2010 and 2017. Histological NAFLD severity was scored using validated criteria. Glomerular filtration rate (GFR) was calculated and categorized as low (<90 mL/min/1.73 m²), normal (90-136 mL/min/1.73 m²), or high (>136 mL/min/1.73 m²). Univariate and multivariate modeling were used to determine differences between the GFR groups and to control for confounders.

RESULTS

The cohort comprised 179 patients (82% non-Hispanic; median age; 14 years; IQR, 12-16 years). One-third of the patients had abnormal renal function, including 36 (20%) with glomerular hyperfiltration and 26 (15%) with low GFR. In multivariable logistic regression, compared with normal GFR, hyperfiltration was independently associated with higher NAFLD activity score (aOR, 2.96; 95% CI, 1.49-5.87; P = .002), after adjusting for age, sex, ethnicity, obesity severity, presence of type 2 diabetes mellitus, and medications.

CONCLUSIONS

In this large cohort with histologically confirmed NAFLD, renal impairment was highly prevalent and associated with liver disease severity, independent of obesity severity. Screening patients with confirmed NAFLD for renal complication is recommended.

Management of Hepatorenal Syndrome: A Review

Acute kidney injury (AKI) occurs frequently in patients with cirrhosis, and hepatorenal syndrome (HRS) is second most common etiology of AKI after volume responsible pre-renal etiology. AKI in these patients negatively impacts pre- and post-transplant patient survival and healthcare burden. Reduced effective blood volume with consequent reduced renal blood flow, along with systemic inflammation in patients with decompensated cirrhosis, result in susceptibility to HRS. In this article, we will review updates over the last 5 years on the changing definition with diagnostic criteria and nomenclature of AKI and HRS, data on medical treatment with vasoconstrictors, and urinary biomarkers in diagnosis of etiology of AKI. We will also discuss the significance of liver transplantation evaluation once the diagnosis of HRS is established and the post-transplant immunosuppression management. We will also review one of the challenging issues that remains among transplant-eligible patients, that of allocation of simultaneous liver kidney transplant. Finally, we will review the new implemented policy from the Organ Procurement Transplant Network on simultaneous liver kidney allocation.

Nonalcoholic Fatty Liver Disease 2020: The State of the Disease

Nonalcoholic fatty liver disease (NAFLD) is the most common liver disease, with a worldwide prevalence of 25%. In the United States, NAFLD and its subtype, nonalcoholic steatohepatitis, affect 30% and 5% of the population, respectively. Considering the ongoing obesity epidemic beginning in childhood, the rise in diabetes, and other factors, the prevalence of NAFLD along with the proportion of those with advanced liver disease is projected to continue to increase. This will have an important impact on public health reflected in health care costs, including impact on the need for liver transplantation, for which nonalcoholic steatohepatitis is already close to becoming the most common indication. NAFLD patients with evidence of nonalcoholic steatohepatitis and advanced fibrosis are at markedly increased risk of adverse outcomes, including overall mortality, and liver-specific morbidity and mortality, respectively. Identification of this cohort of NAFLD patients is paramount, given the associated poorer outcomes, in order to target resources to those who need it most. Various noninvasive tools have been developed in this regard. This review provides an update on the epidemiology, clinical and prognostic features, and diagnostic approach to patients with NAFLD.

Non-alcoholic Fatty Liver Disease: Growing Burden, Adverse Outcomes and Associations

Nonalcoholic fatty liver disease (NAFLD) is a systemic disorder with a complex multifactorial pathogenesis and heterogenous clinical manifestations. NAFLD, once believed to be an innocuous condition, has now become the most common cause of chronic liver disease in many countries worldwide. NAFLD is already highly prevalent in the general population, and owing to a rising incidence of obesity and diabetes mellitus, the incidence of NAFLD and its impact on global healthcare are expected to increase in the future. A subset of patients with NAFLD develops progressive liver disease leading to cirrhosis, hepatocellular carcinoma, and liver failure. NAFLD has emerged as one of the leading causes of cirrhosis and hepatocellular carcinoma in recent years. Moreover, HCC can occur in NAFLD even in absence of cirrhosis. Compared with the general population, NAFLD increases the risk of liver-related, cardiovascular and all-cause mortality. NAFLD is bidirectionally associated with metabolic syndrome. NAFLD increases the risk and contributes to aggravation of the pathophysiology of atherosclerosis, cardiovascular diseases, diabetes mellitus, and chronic kidney disease. In addition, NAFLD is linked to colorectal polyps, polycystic ovarian syndrome, osteoporosis, obstructive sleep apnea, stroke, and various extrahepatic malignancies. Extended resection of steatotic liver is associated with increased risk of liver failure and mortality. There is an increasing trend of NAFLD-related cirrhosis requiring liver transplantation, and the recurrence of NAFLD in such patients is almost universal. This review discusses the growing burden of NAFLD, its outcomes, and adverse associations with various diseases.

Short- and long-term mortality after liver transplantation in patients with and without hepatocellular carcinoma in the UK

Background

The increasing demand for liver transplantation has led to considerable changes in characteristics of donors and recipients. This study evaluated the short- and long-term mortality of recipients with and without hepatocellular carcinoma (HCC) in the UK between 1997 and 2016.

Methods

First-time elective adult liver transplant recipients in the UK were identified and four successive eras of transplantation were compared. Hazard ratios (HRs) comparing the impact of era on short-term (first 90 days) and longer-term (from 90 days to 5 years) mortality were estimated, with adjustment for recipient and donor characteristics.

Results

Some 1879 recipients with and 7661 without HCC were included. There was an increase in use of organs donated after circulatory death (DCD), from 0 per cent in era 1 to 35·2 per cent in era 4 for recipients with HCC, and from 0·2 to 24·1 per cent for non-HCC recipients. The 3-year mortality rate decreased from 28·3 per cent in era 1 to 16·9 per cent in era 4 (adjusted HR 0·47, 95 per cent c.i. 0·35 to 0·63) for recipients with HCC, and from 20·4 to 9·3 per cent (adjusted HR 0·44, 0·36 to 0·53) for those without HCC. Comparing era 4 with era 1, improvements were more marked in short-term than in long-term mortality, both for recipients with HCC (0–90 days: adjusted HR 0·20, 0·10 to 0·39; 90 days to 5 years: adjusted HR 0·52, 0·35 to 0·75; P = 0·043) and for non-HCC recipients (0–90 days: adjusted HR 0·32, 0·24 to 0·42; 90 days to 5 years: adjusted HR 0·52, 0·40 to 0·67; P = 0·024).

Conclusion

In the past 20 years, the mortality rate after liver transplantation has more than halved, despite increasing use of DCD donors. Improvements in overall survival can be explained by decreases in short-term and longer-term mortality.

Plasma Metabolomics Profiling in Maintenance Hemodialysis Patients Based on Liquid Chromatography Quadrupole Time-of-Flight Mass Spectrometry

Background

Key pathogenetic mechanisms underlying renal disease progression are unaffected by current treatment. Metabolite profiling has significantly contributed to a deeper understanding of the biochemical metabolic networks and pathways in disease, but the biochemical details in maintenance hemodialysis (MHD) patients remain largely undefined.

Methods

The metabolic fingerprinting of plasma samples from 19 MHD patients and 12 healthy controls was characterized using liquid chromatography quadrupole time-of-flight mass spectrometry. Principal component analysis (PCA) and orthogonal partial least squares-discriminant analysis (OPLS-DA) were applied to analyze the metabolic data.

Results

The plasma metabolite profile distinguished the MHD patients from the healthy controls successfully by using both PCA and OPLS-DA models. Sixty-three metabolites were identified as the key metabolites to discriminate the MHD patients from healthy controls, involving several metabolic pathways (all p < 0.05). An increase in plasma levels of D-glucose, hippuric acid, androsterone glucuronide, indolelactic acid, and a reduction in plasma levels of glycerophosphocholine, serotonin, L-lactic acid, phytosphingosine, and several lysophosphatidylcholine were observed in MHD patients compared to healthy subjects. Metabolomics analysis combined with KEGG pathway enrichment analysis revealed that non-alcoholic fatty liver disease, choline metabolism in cancer, the forkhead box O signaling pathway, and the hypoxia-inducible factor-1 signaling pathway in MHD patients were significantly changed (p < 0.05).

Conclusion

The identification of a novel signaling pathway and key metabolite markers in MHD patients provides insights into potential pathogenesis and valuable pharmacological targets for end-stage renal disease.

Long-term outcomes after liver transplantation in the Hispanic population

BACKGROUND & AIMS

Racial/ethnic disparities in liver transplantation (LT) are well-recognized. Although Hispanics represent the largest and youngest minority group in the United States, limited data exist on long-term outcomes. We aimed to investigate long-term post-liver transplant outcomes in Hispanic patients and identify potential disparities compared to a baseline demographic of non-Hispanic white patients.

METHODS

We performed a retrospective cohort study of first-time liver transplant recipients using the United Network for Organ Sharing database from 2002 to 2013, with follow-up through 2018. The primary outcomes of interest were overall patient and graft survival after LT.

RESULTS

45 767 patients underwent LT (85.0% non-Hispanic white, 15.0% Hispanic). Hispanics had lower socioeconomic status, higher prevalence of pretransplant comorbidities and more severe liver disease compared to non-Hispanic whites. Hispanics had similar patient (76.6% vs 75.6%; P = .12) and graft (71.7% vs 70.8%; P = .28) survival at 5 years and significantly better patient (62.9% vs 59.7%; P < .001) and graft (58.6% vs 55.6%; P = .002) survival at 10 years. In multivariable analysis, Hispanics had lower associated all-cause mortality (HR 0.86, 95% CI, 0.82-0.91; P < .001) and graft failure (HR 0.89, 95% CI, 0.85-0.93; P < .001) compared to non-Hispanic whites. In etiology-specific subanalysis, Hispanics transplanted for ALD, NASH and HCV had lower all-cause mortality compared to non-Hispanic whites.

CONCLUSIONS

Hispanics have similar or better long-term post-LT outcomes compared to non-Hispanic whites despite a worse pretransplant risk factor profile. Further research is needed to clarify if this survival advantage reflects uncaptured protective factors or more stringent transplant selection in the Hispanic population.

Nonalcoholic Steatohepatitis After Liver Transplantation

Currently, nonalcoholic steatohepatitis (NASH) is the second leading indication for liver transplantation (LT), behind alcohol-related liver disease. After transplant, both recurrent and de novo nonalcoholic fatty liver disease are common; however, recurrence rates of NASH and advanced fibrosis are low. Identification of high-risk groups and optimizing treatment of metabolic comorbidities both before and after LT is paramount to maintaining a healthy allograft, especially with the additional consequences of longterm immunosuppression. In addition, NASH LT recipients are at an increased risk of cardiovascular events and malignancy, and their condition warrants a tailored approach to management. The optimal approach to NASH LT recipients including metabolic comorbidities management, tailored immunosuppression, the role of bariatric surgery, and nutritional and pharmacotherapy of NASH are discussed in this review. Overall, aggressive management of metabolic syndrome after LT via medical and surgical modalities and a minimalist approach to immunosuppression is advised.

Nonalcoholic fatty liver disease increases risk of incident advanced chronic kidney disease: a propensity-matched cohort study

BACKGROUND

As the prevalence of nonalcoholic fatty liver disease (NAFLD) escalates, understanding its potential impact on the development of chronic kidney disease (CKD) is needed.

OBJECTIVE

To determine the longitudinal association of NAFLD with the development of advanced CKD in the United States.

METHODS

A retrospective cohort analysis of the Truven Health MarketScan Database (2006-2015) was conducted. We used Cox proportional hazards models to compare the risk of developing CKD stages 3-5 in patients with NAFLD versus non-NAFLD, identified by ICD-9 codes, after 1:3 propensity score (PS) matching.

RESULTS

In a cohort of 262 619 newly diagnosed patients with NAFLD and 769 878 PS (1:3)-matched non-NAFLD patients, we identified 5766 and 8655 new advanced (stage 3-5) CKD cases, respectively. The crude CKD incidence rate was 8.2 and 5.5 per 1000 person-years in NAFLD and non-NAFLD groups, respectively. In multivariable Cox model, patients with NAFLD had a 41% increased risk of developing advanced CKD compared with non-NAFLD patients [adjusted hazard ratio (aHR), 1.41; 95% confidence interval (CI), 1.36-1.46]. In the sensitivity analysis adjusting for time-varying covariates after NAFLD diagnosis, NAFLD persisted as a significant CKD risk factor (aHR, 1.58; 95% CI, 1.52-1.66) and the association remained significant when stratified by age, gender and pre-existing comorbidities. The risk of CKD increased in NAFLD with compensated cirrhosis (aHR, 1.47; 95% CI, 1.36-1.59) and decompensated cirrhosis (aHR, 2.28; 95% CI, 2.12-2.46).

CONCLUSION

Nonalcoholic fatty liver disease was independently associated with an increased risk of advanced CKD development suggesting renal function screening and regular monitoring are needed in this population.

Liver Transplantation for Nonalcoholic Steatohepatitis: Pathophysiology of Recurrence and Clinical Challenges

Nonalcoholic steatohepatitis is the fastest-growing indication for the liver transplant and a leading cause of hepatocellular carcinoma among patients listed for liver transplantation in the USA. Post-transplant nonalcoholic hepatic steatosis and steatohepatitis are frequent complications of liver transplantation. Nonalcoholic steatohepatitis poses a significant challenge in both pre- and post-transplant period due to its association with metabolic syndrome, coronary artery disease, chronic kidney disease, and obstructive sleep apnea. While optimal therapy is not yet available in the post-liver transplant setting, lifestyle interventions continue to remain as the mainstay of therapy for post-transplant nonalcoholic steatohepatitis. Early recognition with protocol biopsies and noninvasive modalities, along with modification of known risk factors, are the most effective methods to curtail the progression of nonalcoholic steatohepatitis in the absence of FDA-approved pharmacologic therapy.

Renal function after combined liver-kidney transplantation: A longitudinal study of pediatric and adult patients

It has been proposed that the liver protects the kidney in CLKT. However, few studies have examined long-term renal function after CLKT and contrasted renal function of CLKT patients to KT patients beyond one year after transplantation. We studied long-term renal function of CLKT patients and compared renal function of CLKT patients to KT patients between one and five years after transplantation. Patients who underwent CLKT between 1993 and 2011 were included (n = 34; 11 children and 23 adults). Ninety-six (27 children and 69 adults) KT patients were selected as controls. GFR was estimated (eGFR) and measured (mGFR) with ⁵¹ Cr-EDTA clearance. Mean mGFR was 63 at one and 70 at ten years after pediatric CLKT. Mean eGFR was 75 at one and 50 at ten years after adult CLKT. Difference in mean mGFR between pediatric CLKT and KT patients was 8 (95% CI -7 to 23) and 11 (95% CI -4 to 26) at one and five years after transplantation, respectively. Difference in mean eGFR between adult CLKT and KT patients was 8 (95% CI -5 to 20) and 1 (95% CI -10 to 12) at one and five years after transplantation, respectively. Longitudinal changes in GFRs were somewhat similar in CLKT and KT patients in both age-groups but pediatric CLKT patients had on average higher GFRs than pediatric KT patients. In long-term follow-up, renal function remains stable in pediatric CLKT patients but declines in adult CLKT patients.

Effect of Renal Diagnosis on Survival in Simultaneous Liver-Kidney Transplantation

BACKGROUND

Simultaneous liver-kidney transplantation is lifesaving, however, the utility of allocating 2 organs to a single recipient remains controversial, particularly in the face of potentially inferior survival. This study aims to determine the effect of renal indication for transplantation on simultaneous liver-kidney transplantation outcomes.

METHODS

All adult recipients of combined whole liver-kidney transplants in the United Network for Organ Sharing database from 2003 to 2016 with a renal diagnosis of hypertension (HTN), diabetes mellitus (DM), acute tubular necrosis (ATN), or hepatorenal syndrome (HRS) were examined. Comparisons were made between the HTN/DM group and the ATN/HRS group using standard statistical methods.

RESULTS

There were 1,204 patients in the HRS/ATN group vs 1,272 patients in the HTN/DM group. The HTN/DM patients were slightly older (58.1 vs 56.4 years; p < 0.001), more likely to have liver disease due to chronic viral hepatitis (33.2% vs 21.5%; p < 0.001), and less acutely ill (mean Model for End-Stage Liver Disease score of 27.2 vs 33.1; p < 0.001) than their HRS/ATN counterparts. The prevalence of nonalcoholic steatohepatitis was 16.8% in both groups. Donor demographics were similar in both groups, although HTN/DM patients were more likely to have a local (81.6% vs 67.7%; p < 0.001) rather than regional donor. Patient survival rates at 1, 3, and 5 years were significantly lower in the HTN/DM group (87.4%, 78.2%, and 71.2% vs 90.7%, 84.1%, and 76.6%, respectively). Median survival was 118 months for the HTN/DM group vs 139.7 months for the HRS/ATN (p < 0.001). The HTN/DM patients were at significantly higher risk of death (hazard ratio 1.533; p < 0.001), liver graft loss (hazard ratio 1.611; p < 0.001), and renal graft loss (hazard ratio 1.592; p < 0.001) than ATN/HRS patients on multivariable analysis.

CONCLUSIONS

Despite a lower acuity of illness, HTN/DM patients have inferior survival after simultaneous liver-kidney transplantation than those with ATN/HRS. This should be considered in risk adjustment and allocation schemes.

Simultaneous Liver-Kidney Transplantation: Impact on Liver Transplant Patients and the Kidney Transplant Waiting List

Purpose

The number of simultaneous liver-kidney transplants (SLKT) performed in the USA has been rising. The Organ Procurement and Transplantation Network implemented a new policy governing SLKT that specifies eligibility criteria for candidates to receive a kidney with a liver, and creates a kidney waitlist “safety net” for liver recipients with persistent renal failure after transplant. This review explores potential impacts for liver patients and the kidney waitlist.

Recent Findings

Factors that have contributed to the rise in SLKT including Model for End-stage Liver Disease (MELD)-based allocation, regional sharing for high MELD candidates, and the rising incidence of non-alcoholic steatohepatitis will continue to increase the number of liver transplant candidates with concurrent renal insufficiency. The effect of center behavior based on the new policy is harder to predict, given wide historic variability in SLKT practice.

Summary

Continued increase in combined liver/kidney failure is likely, and SLKT and kidney after liver transplant may both increase. Impact of the new policy should be carefully monitored, but influences beyond the policy need to be accounted for.

MELD Stratified Outcomes Among Recipients With Diabetes or Hypertension: Simultaneous Liver Kidney Versus Liver Alone

BACKGROUND AND AIM

Data are scanty on allocating simultaneous liver kidney (SLK) based on model for end-stage disease (MELD) score. Diabetes mellitus (DM) and hypertension (HTN) are frequent in cirrhosis patients. We analyzed transplant recipients with DM and/or HTN to compare MELD-based outcomes of SLK to liver transplantation alone (LTA).

MATERIALS AND METHODS

Of 13,584 first deceased donor liver transplantation among patients with DM and/or HTN (1530 or 11.2% SLK), MELD score predicted SLK [1.02 (1.01-1.03)]. SLK was beneficial for 5-year patient survival at MELD score ≥43 (78.6% vs. 62.6%, P=0.017), but not at MELD score <29 (74.8% vs. 76.2%, P=0.63). Among 11,405 recipients (976 SLK) at MELD score <29, SLK (n=816) was beneficial compared with 706 LTA [75% vs. 64%, P<0.001; 0.71 (0.55-0.91)] at serum creatinine (SC) ≥2 but not at SC<2 [73% vs. 76%, P=0.32; 0.85 (0.60-1.2)]. Among patients with MELD score 29 to 42, SLK (n=484) and LTA (n=1403) had similar survival [69% vs. 69%, P=0.58; 0.9 (0.7-1.5)]. Among patients with MELD score ≥43, SLK (n=70) was associated with 35% improved patient survival at 5 years compared with 222 LTA [0.65 (0.46-0.93)].

CONCLUSIONS

Among patients with DM and/or HTN, SLK is useful at: (a) MELD score <29 and SC≥2 and (b) MELD score ≥43. Prospective studies are needed to confirm these findings as basis to optimize use of SLK.

Biomarkers of Renal Injury in Cirrhosis: Association with Acute Kidney Injury and Recovery after Liver Transplantation

BACKGROUND

To define urine or serum biomarkers in predicting renal function recovery after liver transplantation (LT).

METHODS

Adults listed for LT (February 2011-July 2014) and with modified diet for renal disease-6 (MDRD-6) <60 mL/min provided urine/blood samples at baseline and serially until LT for biomarkers in serum (pg/mL) and urine (pg/mg creatinine).

RESULTS

Of 271 LT listed patients (mean age 57 years, 63% males, median listing MELD 17.5), 1 year acute kidney injury (AKI) probability was 49%, with odds of 1.3-, 3.0-, 4.6-, and 8.5-fold times for listing MELD 16-20, 21-25, 26-30, and >30, compared to MELD <16. Thirty-seven people died over 1 year from the time of listing, with twofold increased odds with AKI. Among 67 patients with MDRD <60, only urinary epidermal growth factor was different comparing AKI (increase in serum creatinine ≥0.3 mg/dL from baseline within past 3 months) vs. no AKI (2,254 vs. 4,253, p = 0.003). Differences between acute tubular necrosis (ATN) and hepatorenal syndrome could not be ascertained for a small sample of 3 patients with ATN. Analyzing 15 of 43 receiving LT and MDRD-6 <30 prior to LT, biomarkers were not different comparing 5 patients recovering renal function (MDRD-6 >50 mL/min) at 6 months vs. 10 without recovery.

CONCLUSIONS

AKI is common among LT listed patients, with a negative impact on transplant-free survival. Serum and urine biomarkers are not associated with the recovery of renal function after LT. Multicenter studies are suggested to (a) develop strategies to reduce the development of AKI and (b) derive novel biomarkers for use in accurately predicting renal recovery after LT.

Outcomes of Simultaneous Liver Kidney Transplantation in Patients With Hepatocellular Carcinoma

BACKGROUND

The frequency of simultaneous liver kidney (SLK) transplantation has increased following the implementation of the model for end-stage liver disease system for liver transplantation (LT). There is a paucity of data evaluating SLK outcomes in patients undergoing LT for hepatocellular carcinoma (HCC). Our aim was to compare outcomes between patients with HCC who underwent SLK and those who received SLK for other indications.

METHODS

We performed a retrospective analysis of adult recipients receiving SLK between 2002 and 2013 from the United Network for Organ Sharing registry. The primary outcome was posttransplant mortality. Patient survival was determined using Kaplan-Meier analysis and predictors of mortality were identified using proportional Cox hazard regression models. Propensity score matching was performed between SLK-HCC and SLK in the absence of HCC (SLK-A) groups to reduce confounding.

RESULTS

Between 2002 and 2013, 186 HCC patients underwent SLK-HCC and 3599 patients underwent SLK-A. The 1-year and 3-year survival rates were 89.0% and 76.7% in the SLK-HCC group and 84.5% and 76.3% in the SLK-A group (P = 0.20). In multivariable Cox regression, HCC was not associated with post-LT survival among all patients (hazard ratio, 1.15; 95% confidence interval, 0.84-1.58) or the propensity score-matched cohort (hazard ratio, 0.97; 95% confidence interval, 0.64-1.47). SLK-HCC patients had similar rates of acute rejection (13.3% vs 10.5%, P = 0.36) and liver graft failure requiring re-transplantation (3.2% vs 2.3%, P = 0.44) compared with SLK-A patients.

CONCLUSIONS

Liver transplant candidates with advanced renal dysfunction and HCC may be considered for SLK.

Association between non-invasively diagnosed hepatic steatosis and chronic kidney disease in Chinese adults on their health check-up

OBJECTIVE

To explore the association between chronic kidney disease (CKD), graded by the estimated glomerular filtration rate (eGFR), and non-alcoholic fatty liver disease (NAFLD) using controlled attenuation parameter (CAP) and fatty liver index (FLI) values in Chinese adults undergoing routine health examinations.

METHODS

A total of 731 adult participants without diabetes mellitus or significant alcohol consumption who underwent routine health examinations were included. Their eGFR, CAP, FLI and abdominal ultrasonography results were assessed.

RESULTS

The prevalence of ultrasound-diagnosed NAFLD and CKD (eGFR <60 mL/min per 1.73 m² ) was 36.1% and 6.6%, respectively. CKD was more common in NAFLD patients than in those without (10.6% vs 4.3%, P < 0.001). The CAP and FLI values were significantly higher in the NAFLD group than in those without, but the change in the eGFR was negligible between the two groups. eGFR was negatively correlated with CAP (r = -0.189, P = 0.003) and FLI values (r = -0.130, P = 0.045). Moreover, eGFR was significantly lower in participants with CAP >292 dBm or FLI ≥60 than in those with CAP <238 dBm or FLI <30, respectively (both P < 0.05). The CAP value (odds ratio [OR] 1.099, 95% confidence interval [CI] 1.091-1.108, P = 0.021) was an independent risk factor for CKD.

CONCLUSIONS

A diagnosis of hepatic steatosis is related to an increased risk of CKD among non-alcoholic and non-diabetic Chinese adults regardless of whether the diagnosis was acquired via ultrasound, CAP or FLI. Increased hepatic lipid content may contribute to CKD development.

NAFLD and liver transplantation: Current burden and expected challenges

Because of global epidemics of obesity and type 2 diabetes, the prevalence of non-alcoholic fatty liver disease (NAFLD) is increasing both in Europe and the United States, becoming one of the most frequent causes of chronic liver disease and predictably, one of the leading causes of liver transplantation both for end-stage liver disease and hepatocellular carcinoma. For most transplant teams around the world this will raise many challenges in terms of pre- and post-transplant management. Here we review the multifaceted impact of NAFLD on liver transplantation and will discuss: (1) NAFLD as a frequent cause of cryptogenic cirrhosis, end-stage chronic liver disease, and hepatocellular carcinoma; (2) prevalence of NAFLD as an indication for liver transplantation both in Europe and the United States; (3) the impact of NAFLD on the donor pool; (4) the access of NAFLD patients to liver transplantation and their management on the waiting list in regard to metabolic, renal and vascular comorbidities; (5) the prevalence and consequences of post-transplant metabolic syndrome, recurrent and de novo NAFLD; (6) the alternative management and therapeutic options to improve the long-term outcomes with particular emphasis on the correction and control of metabolic comorbidities.

Nonalcoholic fatty liver disease - A multisystem disease?

Non-alcoholic fatty liver disease (NAFLD) is one of the most common comorbidities associated with overweight and metabolic syndrome (MetS). Importantly, NAFLD is one of its most dangerous complications because it can lead to severe liver pathologies, including fibrosis, cirrhosis and hepatic cellular carcinoma. Given the increasing worldwide prevalence of obesity, NAFLD has become the most common cause of chronic liver disease and therefore is a major global health problem. Currently, NAFLD is predominantly regarded as a hepatic manifestation of MetS. However, accumulating evidence indicates that the effects of NAFLD extend beyond the liver and are negatively associated with a range of chronic diseases, most notably cardiovascular disease (CVD), diabetes mellitus type 2 (T2DM) and chronic kidney disease (CKD). It is becoming increasingly clear that these diseases are the result of the same underlying pathophysiological processes associated with MetS, such as insulin resistance, chronic systemic inflammation and dyslipidemia. As a result, they have been shown to be independent reciprocal risk factors. In addition, recent data have shown that NAFLD actively contributes to aggravation of the pathophysiology of CVD, T2DM, and CKD, as well as several other pathologies. Thus, NAFLD is a direct cause of many chronic diseases associated with MetS, and better detection and treatment of fatty liver disease is therefore urgently needed. As non-invasive screening methods for liver disease become increasingly available, detection and treatment of NAFLD in patients with MetS should therefore be considered by both (sub-) specialists and primary care physicians.

Fatty Liver and Chronic Kidney Disease: Novel Mechanistic Insights and Therapeutic Opportunities

Chronic kidney disease (CKD) is a risk factor for end-stage renal disease (ESRD) and cardiovascular disease (CVD). ESRD or CVD develop in a substantial proportion of patients with CKD receiving standard-of-care therapy, and mortality in CKD remains unchanged. These data suggest that key pathogenetic mechanisms underlying CKD progression go unaffected by current treatments. Growing evidence suggests that nonalcoholic fatty liver disease (NAFLD) and CKD share common pathogenetic mechanisms and potential therapeutic targets. Common nutritional conditions predisposing to both NAFLD and CKD include excessive fructose intake and vitamin D deficiency. Modulation of nuclear transcription factors regulating key pathways of lipid metabolism, inflammation, and fibrosis, including peroxisome proliferator-activated receptors and farnesoid X receptor, is advancing to stage III clinical development. The relevance of epigenetic regulation in the pathogenesis of NAFLD and CKD is also emerging, and modulation of microRNA21 is a promising therapeutic target. Although single antioxidant supplementation has yielded variable results, modulation of key effectors of redox regulation and molecular sensors of intracellular energy, nutrient, or oxygen status show promising preclinical results. Other emerging therapeutic approaches target key mediators of inflammation, such as chemokines; fibrogenesis, such as galectin-3; or gut dysfunction through gut microbiota manipulation and incretin-based therapies. Furthermore, NAFLD per se affects CKD through lipoprotein metabolism and hepatokine secretion, and conversely, targeting the renal tubule by sodium-glucose cotransporter 2 inhibitors can improve both CKD and NAFLD. Implications for the treatment of NAFLD and CKD are discussed in light of this new therapeutic armamentarium.

Metabolic syndrome and non-alcoholic fatty liver disease after liver or kidney transplantation

Transplantation is a definitive treatment option for patients with end-stage liver disease, and for some patients with acute liver failure, hepatocellular carcinoma or end-stage renal disease. Long-term post-transplantation complications have become an important medical issue, and cardiovascular diseases (CVD) are now the leading cause of mortality in liver or kidney transplant recipients. The increased prevalence of metabolic syndrome (MS) likely plays a role in the high incidence of post-transplantation CVD. MS and its hepatic manifestation, non-alcoholic fatty liver disease (NAFLD), are prevalent among the general population and in pre- and post-transplantation settings. MS components are associated with recurrent or de novo NAFLD in transplant recipients, potentially influencing post-transplantation survival. Moreover, recent data reveal an important association between NAFLD and risk of incident of chronic kidney disease (CKD). Therefore, NAFLD identification could represent an additional clinical feature for improving the stratification of liver and kidney transplant recipients with regards to risks of CVD, CKD and renal allograft dysfunction. All MS components are potentially modifiable; therefore, it is crucial that hepatologists, nephrologists and primary care physicians become more engaged in managing post-transplantation metabolic complications. The present review discusses the recent clinical evidence regarding the importance of MS and its components after liver and kidney transplantation, as well as the link between MS and NAFLD after liver and kidney transplantation.

Nonalcoholic Steatohepatitis is the Most Rapidly Growing Indication for Simultaneous Liver Kidney Transplantation in the United States

BACKGROUND

Frequency of liver transplantation (LT) is increasing in nonalcoholic steatohepatitis (NASH) with good post-transplant outcomes. Similar data on simultaneous liver kidney (SLK) transplants are limited.

METHODS

United Network for Organ Sharing database (2002-2011) queried for deceased donor first LT for primary biliary cirrhosis, primary sclerosing cholangitis, or alcoholic cirrhosis (group I), NASH, and cryptogenic cirrhosis with body mass index greater than 30 (group II), and hepatitis C virus with and without alcohol, hepatitis B virus, and hepatocellular carcinoma (group III).

RESULTS

Of 38 533 LT (9495, 3665, and 25 383 in groups I-III, respectively), about 5.6% (N = 2162) received SLK with 584 (6.2%), 320 (8.7%), and 1258 (5%) in groups I-III, respectively. The SLK performed for group II increased from 6.3% in 2002 to 2003 to 19.2% in 2010 to 2011. Similar trends remained unchanged in group I (26.1 to 26.6%) and decreased in group III (67.6 to 54.5%). Five-year outcomes were similar comparing group II versus group I for liver graft (78 vs 74%, P = 0.14) and patient survival (81 vs 76%, P = 0.07). In contrast, kidney graft outcome was worse for group II (70 vs 79%, P = 0.002). Risk of kidney graft loss was over 1.5-fold higher among group II SLK recipients compared to group I after controlling for recipient characteristics. Estimated glomerular filtration rate remained lower in group II compared with group I at various time points after SLK transplantation.

CONCLUSIONS

The NASH is the most rapidly growing indication for SLK transplantation with poor renal outcomes. Studies are needed to examine mechanisms of these findings and develop strategies to improve renal outcomes in SLK recipients for NASH.

Nonalcoholic Fatty Liver Disease and Liver Transplantation

Nonalcoholic fatty liver disease (NAFLD) is prevalent in the general population and a growing indication for liver transplant. Longer wait times and challenges with pretransplant survivorship are expected, underscoring the need for improved management of attendant comorbidities. Recognition with potential modification of obesity, sarcopenia, chronic kidney disease, and cardiovascular disease in patients with NAFLD may have important implications in the pretransplant and posttransplant periods. Although patients with NAFLD have generally favorable postoperative outcomes, they are at risk for developing recurrent disease in their allograft, driving the need for pharmacotherapies and dietary innovations appropriate for use in the posttransplant period.

Nonalcoholic Fatty Liver Disease: Key Considerations Before and After Liver Transplantation

Nonalcoholic fatty liver disease (NAFLD) is the most common etiology of chronic liver disease in developed countries and is on trajectory to become the leading indication for liver transplantation in the USA and much of the world. Patients with NAFLD cirrhosis awaiting liver transplant face unique challenges and increased risk for waiting list stagnation and dropout due to burdensome comorbidities including obesity, diabetes, cardiovascular disease, and kidney disease. Thus far, patients transplanted for NAFLD cirrhosis have excellent mid- and long-term patient and graft survival, but concerns regarding short-term morbidity and mortality continue to exist. Post-liver transplantation, NAFLD occurs as both a recurrent and de novo manifestation, each with unique outcomes. NAFLD in the donor population is of concern given the growing demand for liver transplantation and mounting pressure to expand the donor pool. This review addresses key issues surrounding NAFLD as an indication for transplantation, including its increasing prevalence, unique patient demographics, outcomes related to liver transplantation, development of post-liver transplantation NAFLD, and NAFLD in the liver donor population. It also highlights exciting areas where further research is needed, such as the role of bariatric surgery and preconditioning of marginal donor grafts.

NAFLD and Chronic Kidney Disease

Non-alcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease in developed countries and it is now considered a risk factor for cardiovascular disease. Evidence linking NAFLD to the development and progression of chronic kidney disease (CKD) is emerging as a popular area of scientific interest. The rise in simultaneous liver-kidney transplantation as well as the significant cost associated with the presence of chronic kidney disease in the NAFLD population make this entity a worthwhile target for screening and therapeutic intervention. While several cross-sectional and case control studies have been published to substantiate these theories, very little data exists on the underlying cause of NAFLD and CKD. In this review, we will discuss the most recent publications on the diagnosis of NAFLD as well new evidence regarding the pathophysiology of NAFLD and CKD as an inflammatory disorder. These mechanisms include the role of obesity, the renin-angiotensin system, and dysregulation of fructose metabolism and lipogenesis in the development of both disorders. Further investigation of these pathways may lead to novel therapies that aim to target the NAFLD and CKD. However, more prospective studies that include information on both renal and liver histology will be necessary in order to understand the relationship between these diseases.

Long-Term Outcomes of Simultaneous Liver-Kidney Transplant Patients with Hepatitis B Compared to with Liver Transplant Alone

BACKGROUND

The number and survival rate of simultaneous liver-kidney transplant (SLKT) recipients have increased dramatically since 2002. However, the long-term effectiveness of SLKT in patients with hepatitis B is unknown.

MATERIAL/METHODS

Forty-six patients who visited the Organ Transplant Center of the Shanghai First People's Hospital between January 2001 and May 2005 had hepatitis B virus infection and renal failure (any degree), and underwent organ transplantation: 21 patients underwent SLKT and 25 patients underwent liver transplant (LT) alone.

RESULTS

The 1-, 3-, and 5-year survival rates of SLKT recipients were 90.5%, 81.0%, and 81.0%, respectively. Incidence of acute hepatic allograft rejection between SLKT recipients and LT recipients (33% vs. 16%) did not reach significance (P=0.170). Despite higher infection rate, more prevalent hepatitis B relapse, and longer stay in the intensive care unit, SLKT recipients experienced significantly higher 1-year survival rate (90.5%) compared with LT recipients (60%, P=0.019). Multivariate regression analysis revealed that postoperative renal failure (odds ratio (OR)=48, P=0.003) and Risk/Injury/Failure/Loss/End-stage (RIFLE) stage (OR=8, P=0.012) were independent risk factors for postoperative death after LT.

CONCLUSIONS

SLKT in patients with hepatitis B had higher early-stage infection rate, but had a higher long-term survival rate compared with the LT group. Although the incidence of postoperative hepatitis B relapse in SLKT recipients was higher, timely and reasonable treatment can ensure long-term survival of patients. Worsening RIFLE stage of recipients can predict high mortality when only given LT. SLKT might be a better choice for RIFLE stage 2 or 3 patients than LT alone.

Decreased chronic cellular and antibody-mediated injury in the kidney following simultaneous liver-kidney transplantation

In simultaneous liver-kidney transplantation (SLK), the liver can protect the kidney from hyperacute rejection and may also decrease acute cellular rejection rates. Whether the liver protects against chronic injury is unknown. To answer this we studied renal allograft surveillance biopsies in 68 consecutive SLK recipients (14 with donor-specific alloantibodies at transplantation [DSA+], 54 with low or no DSA, [DSA-]). These were compared with biopsies of a matched cohort of kidney transplant alone (KTA) recipients (28 DSA+, 108 DSA-). Overall 5-year patient and graft survival was not different: 93.8% and 91.2% in SLK, and 91.9% and 77.1% in KTA. In DSA+ recipients, KTA had a significantly higher incidence of acute antibody-mediated rejection (46.4% vs. 7.1%) and chronic transplant glomerulopathy (53.6% vs. 0%). In DSA- recipients at 5 years, KTA had a significantly higher cumulative incidence of T cell-mediated rejection (clinical plus subclinical, 30.6% vs. 7.4%). By 5 years, DSA+ KTA had a 44% decline in mean GFR while DSA+SLK had stable GFR. In DSA- KTA, the incidence of a combined endpoint of renal allograft loss or over a 50% decline in GFR was significantly higher (20.4% vs. 7.4%). Simultaneously transplanted liver allograft was the most predictive factor for a significantly lower incidence of cellular (odds ratio 0.13, 95% confidence interval 0.06-0.27) and antibody-mediated injury (odds ratio 0.11, confidence interval 0.03-0.32), as well as graft functional decline (odds ratio 0.22, confidence interval 0.06-0.59). Thus, SLK is associated with reduced chronic cellular and antibody-mediated alloimmune injury in the kidney allograft.

Impact of renal impairment on cardiovascular disease mortality after liver transplantation for nonalcoholic steatohepatitis cirrhosis

BACKGROUND & AIMS

Non-alcoholic steatohepatitis (NASH) is an independent risk factor for cardiovascular disease (CVD) morbidity after liver transplantation, but its impact on CVD mortality is unknown. We sought to assess the impact of NASH on CVD mortality after liver transplantation and to predict which NASH recipients are at highest risk of a CVD-related death following a liver transplant.

METHODS

Using the Organ Procurement and Transplantation Network database, we examined associations between NASH and post-liver transplant CVD mortality, defined as primary cause of death from thromboembolism, arrhythmia, heart failure, myocardial infarction or stroke. A physician panel reviewed cause of death.

RESULTS

Of 48 360 liver transplants (2/2002-12/2011), 5057 (10.5%) were performed for NASH cirrhosis. NASH recipients were more likely to be older, female, obese, diabetic and have history of renal failure or prior CVD vs. non-NASH (P < 0.001 for all). Although there was no difference in overall all-cause mortality (log-rank P = 0.96), both early (30-day) and long-term CVD-specific mortality was increased among NASH recipients (Odds ratio = 1.30, 95% Confidence interval (CI): 1.02-1.66; Hazard ratio = 1.42, 95% CI: 1.07-1.41 respectively). These associations were no longer significant after adjustment for pre-transplant diabetes, renal impairment or CVD. A risk score comprising age ≥55, male sex, diabetes and renal impairment was developed for prediction of post-liver transplant CVD mortality (c-statistic 0.60).

CONCLUSION

NASH recipients have an increased risk of CVD mortality after liver transplantation explained by a high prevalence of comorbid cardiometabolic risk factors that in aggregate identify those at highest risk of post-transplant CVD mortality.

Nonalcoholic Fatty Liver Disease (NAFLD)-A New Cardiovascular Risk Factor in Peritoneal Dialysis Patients

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BACKGROUND

Recent investigations indicated that nonalcoholic fatty liver disease (NAFLD), a hepatic component of metabolic syndrome (MS), is associated with an increased risk of cardiovascular disease (CVD). Accordingly, we were interested in exploring the frequency of NAFLD in peritoneal dialysis (PD) patients and analyzing factors in PD patients associated with NAFLD occurrence. In addition, we were interested in investigating whether NAFLD is associated with higher CVD risk in our PD patients. ♦

METHODS

In the present cross-sectional study, we analyzed 58 PD patients. The controlled attenuation parameter (CAP) was used to detect and quantify liver steatosis with the help of transient elastography (TE) (FibroScan, Echosense SA, Paris, France). A carotid ultrasound was performed in all patients to measure carotid intimae media thickness (IMT) and plaque as surrogate measures of increased CVD risk, and we investigated their association with NAFLD. ♦

RESULTS

Nonalcoholic fatty liver disease was present in 74.1% of PD patients. Peritoneal dialysis/nonalcoholic fatty liver disease patients had statistically greater daily (136.5 ± 62.6 vs 93.6 ± 36.1; p = 0.02) and monthly (4,095.3 ± 1,877.7 vs 2,806.6 ± 1,083.2; p = 0.02) glucose load in comparison to the non-NAFLD/PD patients. In the next step, we were interested in analyzing what demographic and clinical characteristics in our PD patients are associated with a higher NAFLD occurrence. Presence of diabetes mellitus (DM), arterial hypertension (AH), dyslipidemia, body mass index > 25 kg/m(2), and daily glucose load > 100 g were associated with NAFLD occurrence. Peritoneal dialysis patients with NAFLD showed more carotid atherosclerosis than PD patients without NAFLD. In addition, CAP values (as indicator of liver steatosis) showed strong positive association with IMT (r = 0.801; p < 0.0001). Nonalcoholic fatty liver disease was a strong predictor of carotid atherosclerosis in PD patients. ♦

CONCLUSION

Nonalcoholic fatty liver disease is highly prevalent in PD patients. Peritoneal dialysis patients with NAFLD are at high risk of atherosclerosis. Assessment of NAFLD in PD patients may be helpful for CVD risk stratification.