NAFLD recurrence in liver transplant recipients

Liver Allograft Cirrhosis, Retransplant, and Mortality Secondary to Recurrent Disease After Transplant for MASH: A Systematic Review and Meta-analysis

BACKGROUND

Recurrent disease after liver transplant is well recognized for many diseases. Metabolic dysfunction-associated steatotic liver disease (MASLD) and steatohepatitis (MASH) are leading indications for liver transplant, and there is scarce knowledge about recurrence-related end outcomes such as retransplant and mortality. This project aims to assess the proportion of patients transplanted for MASH who develop recurrent disease and adverse clinical outcomes.

METHODS

A systematic review and pooled proportions meta-analysis was performed by searching the following databases: MEDLINE, Embase, Scopus, Web of Science Core Collection, and Cochrane Library. Inclusion criteria were studies discussing adult patients with liver transplants secondary to MASH or presumed MASH with recurrent disease-related outcomes. Outcomes were assessed in time frames from <6 mo to ≥5 y.

RESULTS

Of 5859 records, 40 were included (16 157 patients). Recurrent MASLD and MASH (28 studies each) occurred in frequencies of 35%-49% and 11%-24%, respectively. Fibrosis occurred in 4%-25% (13 studies). Recurrent disease-related cirrhosis (13 studies), graft failure (8 studies), and retransplant (9 studies) occurred in 0%-2%, 3%-9%, and 0%-1%, respectively. Recurrent disease-related hepatocellular carcinoma (1 study) and mortality (17 studies) both had a prevalence of 0%. Studies were of moderate or high quality using the Methodological Index for Non-Randomized Studies tool.

CONCLUSIONS

Recurrent MASLD and MASH after liver transplant occur frequently, but adverse clinical outcomes due to disease recurrence are infrequent, maybe due to insufficient data on long-term follow-up. Long-term outcomes after transplantation for MASLD appear favorable; however, identifying those more likely to have progressive recurrent disease leading to adverse clinical outcomes may allow for pre- and posttransplant interventions to improve outcomes further.

Utilizing Machine Learning to Predict Liver Allograft Fibrosis by Leveraging Clinical and Imaging Data

BACKGROUND AND AIM

Liver transplant (LT) recipients may succumb to graft-related pathologies, contributing to graft fibrosis (GF). Current methods to diagnose GF are limited, ranging from procedural-related complications to low accuracy. With recent advances in machine learning (ML), we aimed to develop a noninvasive tool using demographic, clinical, laboratory, and B-mode ultrasound (US) features to predict significant fibrosis (METAVIR≥F2).

METHODS

We used a nested 10-fold cross-validation approach with grid-search for hyperparameter fine-tuning to train an artificial neural network (ANN) and a support vector machine (SVM) to classify mild fibrosis (F0-F1) and significant fibrosis (F2-F4) on 1131 patients. We calculated Shapley values to identify top-ranked features, determining the contribution of each feature to model predictions. For the imaging-based model, we used 4819 images with 892 studies trained on the residual network 18 (ResNet18) model to classify F0-F1 versus F3-F4.

RESULTS

We determined the ANN performed the best when compared to the SVM and standard biomarkers, with an AUC ranging from 0.77 to 0.81. The ResNet18 model was unable to diagnose advanced GF, leading to the training AUCs ranging from 0.89 to 0.97, while the validation and testing AUCs were 0.43-0.63. Shapley analysis highlighted the following top-ranked features associated with significant GF: hepatitis C at transplant, recipient age, recipient sex, and certain blood markers such as creatinine and hemoglobin.

CONCLUSION

Noninvasive approaches using ML for predicting significant GF perform well when considering demographic, clinical, and laboratory data; however, this performance is not enhanced with the use of US images.

Metabolic-Dysfunction-Associated Steatotic Liver Disease (MASLD) after Liver Transplantation: A Narrative Review of an Emerging Issue

The development of steatotic liver disease after liver transplant (LT) is widely described, and epidemiological data have revealed an increased incidence in recent times. Its evolution runs from simple steatosis to steatohepatitis and, in a small proportion of patients, to significant fibrosis and cirrhosis. Apparently, post-LT steatotic disease has no impact on the recipient's overall survival; however, a higher cardiovascular and malignancy burden has been reported. Many donors' and recipients' risk factors have been associated with this occurrence, although the recipient-related ones seem of greater impact. Particularly, pre- and post-LT metabolic alterations are strictly associated with steatotic graft disease, sharing common pathophysiologic mechanisms that converge on insulin resistance. Other relevant risk factors include genetic variants, sex, age, baseline liver diseases, and immunosuppressive drugs. Diagnostic evaluation relies on liver biopsy, although non-invasive methods are being increasingly used to detect and monitor both steatosis and fibrosis stages. Management requires a multifaceted approach focusing on lifestyle modifications, the optimization of immunosuppressive therapy, and the management of metabolic complications. This review aims to synthesize the current knowledge of post-LT steatotic liver disease, focusing on the recent definition of metabolic-dysfunction-associated steatotic liver disease (MASLD) and its metabolic and multisystemic concerns.

Post-transplant Non-alcoholic Fatty Liver Disease and Metabolic Syndrome After Living Donor Liver Transplantation in Indians

Background

Post-transplant non-alcoholic fatty liver disease (NAFLD) is common but is not well described in the living donor liver transplantation (LDLT) setting.

Methods

The study was conducted at a large volume LDLT center in north India. Adult (age >18 years at the time of transplant) liver transplantation (LT) recipients were included. Patients with any history of alcohol use were excluded. The study was conducted prospectively from July 2022 to April 2023, and all patients with a minimum of 1-year follow-up after transplant attending outpatient services were included. NAFLD was diagnosed by ultrasound showing steatosis in the absence of other etiologies.

Results

The study cohort included 103 males and 14 females, aged 48 ± 10 years at the time of LT and 53 ± 10 years at the time of inclusion in the study. The median follow-up from LT was 62 (32-97 months). A total of 39 (33%) patients suffered from post-LT NAFLD. NAFLD was recurrent in 9/23 (39%, in patients with NASH or cryptogenic cirrhosis as etiology of LT) and de novo in 30/94 (31%). Pre and post-LT higher body mass index, presence of diabetes and higher serum triglycerides values were associated with the development of post-LT NAFLD. Post-transplant metabolic syndrome was present in 58/95 (61%) LDLT recipients using HbA1c 5.7 to 6.4 as a marker of prediabetes.

Conclusion

Post-LT NAFLD was present in one-third of the patients and metabolic syndrome in the majority of the patients at a median follow-up of 62 months after LDLT.

Pancreatic steatosis is an independent risk factor for post-transplant diabetes mellitus in kidney transplant patients

BACKGROUND AND AIM

Post-transplant diabetes mellitus (PTDM) is associated with an increased risk of post-transplant cardiovascular diseases, and several risk factors of PTDM have been shown in the literature. Yet, the relationship between hepatic and pancreatic steatosis with post-transplant diabetes mellitus remains vague. We aimed to evaluate pancreatic steatosis, a novel component of metabolic syndrome, and hepatic steatosis association with post-transplant diabetes mellitus in a single-center retrospective cohort study conducted on kidney transplant recipients.

METHOD

We have performed a single-center retrospective cohort study involving all kidney transplant recipients. We have utilized pretransplant Fibrosis-4, nonalcoholic fatty liver disease fibrosis score, and abdominal computed tomography for the assessment of visceral steatosis status.

RESULTS

We have included 373 kidney transplant recipients with a mean follow-up period of 32 months in our final analysis. Post-transplant diabetes mellitus risk is associated with older age (p < .001), higher body-mass index (p < .001), nonalcoholic fatty liver disease-fibrosis score (p = .002), hepatic (p < .001) or pancreatic (p < .001) steatosis on imaging and higher pre-transplant serum triglyceride (p = .003) and glucose levels (p = .001) after multivariate analysis.

CONCLUSION

Our study illustrates that recipients' pancreatic steatosis is an independent predictive factor for post-transplant diabetes mellitus including in kidney transplant patients.

The Outcomes of Liver Transplantation in Severe Metabolic Dysfunction-Associated Steatotic Liver Disease Patients

The increasing prevalence of diabetes mellitus, obesity, and metabolic syndrome in the population can lead to metabolic dysfunction-associated steatohepatitis (MASH) and metabolic dysfunction-associated steatotic liver disease (MASLD). In Western industrialized countries, this has become a major problem with significant socioeconomic impacts. MASH is now a leading cause of liver transplantation (LT), especially in developed countries. However, the post-transplant outcomes of such patients are a major concern, and published data are limited and extremely variable. In this article, we discuss graft and patient survival after LT, complications, the recurrence of MASH, and MASH appearing de novo after transplantation. Recent studies suggest that patients with MASH have slightly worse short-term survival, potentially due to increased cardiovascular mortality. However, most studies found that longer-term outcomes for patients undergoing LT for MASH are similar or even better than those for other indications. Hepatocellular carcinoma due to MASH cirrhosis also has similar or even better outcomes after LT than other etiologies. In conclusion, we suggest questions and topics that require further research to enhance healthcare for this growing patient population.

A Comprehensive Review of Liver Allograft Fibrosis and Steatosis: From Cause to Diagnosis

Despite advances in posttransplant care, long-term outcomes for liver transplant recipients remain unchanged. Approximately 25% of recipients will advance to graft cirrhosis and require retransplantation. Graft fibrosis progresses in the context of de novo or recurrent disease. Recurrent hepatitis C virus infection was previously the most important cause of graft failure but is now curable in the majority of patients. However, with an increasing prevalence of obesity and diabetes and nonalcoholic fatty liver disease as the most rapidly increasing indication for liver transplantation, metabolic dysfunction-associated liver injury is anticipated to become an important cause of graft fibrosis alongside alloimmune hepatitis and alcoholic liver disease. To better understand the landscape of the graft fibrosis literature, we summarize the associated epidemiology, cause, potential mechanisms, diagnosis, and complications. We additionally highlight the need for better noninvasive methods to ameliorate the management of graft fibrosis. Some examples include leveraging the microbiome, genetic, and machine learning methods to address these limitations. Overall, graft fibrosis is routinely seen by transplant clinicians, but it requires a better understanding of its underlying biology and contributors that can help inform diagnostic and therapeutic practices.

Liver Transplant Outcomes in Young Adults with Cirrhosis Related to Nonalcoholic Fatty Liver Disease

BACKGROUND

The prevalence of nonalcoholic fatty liver disease (NASH) and cryptogenic cirrhosis (CC) is constantly increasing in adolescents and young adults (AYAs).

METHODS

In a retrospective UNOS database evaluation, we analyzed postoperative outcomes of AYAs with nonalcoholic NASH/CC undergoing LT between January 1st, 2003 and March 5th, 2021. After exclusions, 85,970 LT recipients, 393 (47.1%) AYAs with NASH/CC and 441 (52.9%) AYAs with other metabolic conditions, were analyzed.

RESULTS

During the study period, the number of LTs performed for AYAs with NASH/CC increased from 4%-7% but decreased from 6.6%-5.3% compared to LTs performed for NASH/CC in all ages. In comparison to AYAs with other metabolic conditions, AYA LT recipients with NASH/CC had a higher prevalence of metabolic syndrome (MetS) components, including diabetes and increased body mass index (P < .0001 for both). Patient and graft survival in AYAs with NASH/CC were significantly lower in comparison to AYAs transplanted for other metabolic conditions (P < .0001) (Hazard Ratio = 1.93, P < .001). Patient survival in AYAs with NASH/CC was significantly better in comparison to older (40-65-year-old) patients with the same diagnosis (P = .01).

CONCLUSIONS

Our study found that the overall number of LTs in AYAs with NASH increased significantly, but to a lesser degree compared to the older population with the same diagnosis. Outcomes after LT in AYAs with NASH/CC were worse compared to LT for other metabolic conditions, but significantly better in comparison to older patients. The prevalence of LT for NASH/CC in AYAs is growing. MetS may contribute to worse outcomes in AYAs.

Evolving challenges with long-term care of liver transplant recipients

The number of liver transplants (LT) performed worldwide continues to rise, and LT recipients are living longer post-transplant. This has led to an increasing number of LT recipients requiring lifelong care. Optimal care post-LT requires careful attention to both the allograft and systemic issues that are more common after organ transplantation. Common causes of allograft dysfunction include rejection, biliary complications, and primary disease recurrence. While immunosuppression prevents rejection and reduces incidences of some primary disease recurrence, it has detrimental systemic effects. Most commonly, these include increased incidences of metabolic syndrome, various malignancies, and infections. Therefore, it is of utmost importance to optimize immunosuppression regimens to prevent allograft dysfunction while also decreasing the risk of systemic complications. Institutional protocols to screen for systemic disease and heightened clinical suspicion also play an important role in providing optimal long-term post-LT care. In this review, we discuss these common complications of LT as well as unique considerations when caring for LT recipients in the years after transplant.

Behaviour regulation and the role of mental health in non-alcoholic fatty liver disease

BACKGROUND AND AIMS

Non-alcoholic fatty liver disease (NAFLD) has become the most common cause of chronic liver disease in wealthy societies, and is responsible for a significant rise in liver morbidity and mortality. Current treatments prioritise lifestyle interventions, predominantly diet and exercise management, but patients frequently fail to make the necessary behavioural adjustments. The current study seeks to identify those factors which influence patients' behaviour with respect to adherence to treatment regimes.

METHODS

Novel areas of interest were investigated; locus of control, behavioural regulation and a range of mental health measures, due to their links to either poor lifestyle choices or abnormal eating as identified in previous literature. Data was gathered using self-report questionnaires, from 96 participants, who were split into three groups, NAFLD patients, non-NAFLD liver disease patients and healthy controls RESULTS: Data was analysed using a MANOVA, and followed up with a Tukey post-hoc test. Three factors were found to be significant by group; cognitive restraint, uncontrolled eating and SAPAS score (a measure of personality disorders). An association between personality disorders and NAFLD was identified.

CONCLUSION

It is suggested that NAFLD patients are screened for personality disorders and, if identified, treated prior to the commencement of diet and exercise management.

European Society for Organ Transplantation Consensus Statement on Biomarkers in Liver Transplantation

Currently, one-year survival following liver transplantation (LT) exceeds 90% in large international registries, and LT is considered definitive treatment for patients with end-stage liver disease and liver cancer. Recurrence of disease, including hepatocellular carcinoma (HCC), significantly hampers post-LT outcomes. An optimal approach to immunosuppression (IS), including safe weaning, may benefit patients by mitigating the effect on recurrent diseases, as well as reducing adverse events associated with over-/under-IS, including chronic kidney disease (CKD). Prediction of these outcome measures-disease recurrence, CKD, and immune status-has long been based on relatively inaccurate clinical models. To address the utility of new biomarkers in predicting these outcomes in the post-LT setting, the European Society of Organ Transplantation (ESOT) and International Liver Transplant Society (ILTS) convened a working group of experts to review literature pertaining to primary disease recurrence, development of CKD, and safe weaning of IS. Summaries of evidence were presented to the group of panelists and juries to develop guidelines, which were discussed and voted in-person at the Consensus Conference in Prague November 2022. The consensus findings and recommendations of the Liver Working Group on new biomarkers in LT, clinical applicability, and future needs are presented in this article.

Hepatic steatosis after liver transplantation: a systematic review and meta-analysis

NAFLD can occur after liver transplantation (LT), as recurrence or de novo hepatic steatosis (HS). We aimed to evaluate the literature on prevalence, risk factors, and prognosis of post-LT HS. Systematic review with meta-analysis through a search on: PUBMED, Scopus, and Web-of-Science, from inception until the September 30, 2021. Forty studies were included, representing 6979 patients. The post-LT HS prevalence was 39.76% (95% CI, 34.06-45.46), with a rising kinetics (11.06% increase per decade, p =0.04), and a geographical distribution (15.10% more prevalent in American continent compared with Europe and Asia). Recurrent HS was up to 5-fold more likely than de novo HS [OR: 5.38 (2.69-10.76)]. Metabolic disturbances were stronger risk factors in the post-LT recipient [obesity: OR: 4.62 (3.07-6.96); metabolic syndrome: OR: 3.26 (2.03-5.25)] as compared with pre-LT recipients, with the exception of diabetes mellitus, which doubled the risk at any set [pre-LT diabetes mellitus: OR: 2.06 (1.58-2.68); post-LT diabetes mellitus: OR: 2.12 (1.73-2.59)]. Donor factors were not the relevant risk factors for post-LT HS and the only immunosuppressive drug associated with increased risk was sirolimus [OR: 1.68 (1.07-2.64)]. The prevalence of post-LT steatohepatitis was 28.82% (19.62-38.03) and the strongest risk factor was pre-LT NAFLD. Limited outcomes data suggest that post-LT HS did not increase the risk for liver cirrhosis or mortality in these studies. Two out of 5 patients submitted to LT will develop post-LT HS, being recurrent HS more common than de novo HS. Diabetes mellitus and post-LT metabolic syndrome are the strongest risk factors for HS and baseline NAFLD for steatohepatitis. All transplanted patients should be enrolled in lifestyle interventions to prevent post-LT metabolic syndrome, and sirolimus should be avoided in high-risk patients.

Collagen matrix scaffolds: Future perspectives for the management of chronic liver diseases

Approximately 1.5 billion chronic liver disease (CLD) cases have been estimated worldwide, encompassing a wide range of liver damage severities. Moreover, liver disease causes approximately 1.75 million deaths per year. CLD is typically characterized by the silent and progressive deterioration of liver parenchyma due to an incessant inflammatory process, cell death, over deposition of extracellular matrix proteins, and dysregulated regeneration. Overall, these processes impair the correct function of this vital organ. Cirrhosis and liver cancer are the main complications of CLD, which accounts for 3.5% of all deaths worldwide. Liver transplantation is the optimal therapeutic option for advanced liver damage. The liver is one of the most common organs transplanted; however, only 10% of liver transplants are successful. In this context, regenerative medicine has made significant progress in the design of biomaterials, such as collagen matrix scaffolds, to address the limitations of organ transplantation (e.g., low donation rates and biocompatibility). Thus, it remains crucial to continue with experimental and clinical studies to validate the use of collagen matrix scaffolds in liver disease.

Liver transplantation for non-alcoholic fatty liver disease: indications and post-transplant management

Non-alcoholic fatty liver disease (NAFLD) is currently the fastest growing indication to liver transplantation (LT) in Western Countries, both for end stage liver disease and hepatocellular carcinoma. NAFLD/non-alcoholic steatohepatitis (NASH) is often expression of a systemic metabolic syndrome; therefore, NAFLD/NASH patients require a multidisciplinary approach for a proper pre-surgical evaluation, which is important to achieve a post-transplant outcome comparable to that of other indications to LT. NAFLD/NASH patients are also at higher risk of post-transplant cardiovascular events, diabetes, dyslipidemia, obesity, renal impairment and recurrent NASH. Lifestyle modifications, included diet and physical activity, are key to improve survival and quality of life after transplantation. A tailored immunosuppressive regimen may be proposed in selected patients. Development of new drugs for the treatment of recurrent NASH is awaited.

Inevitability of disease recurrence after liver transplantation for NAFLD cirrhosis

Background & Aims

Liver transplantation (LT) is the only available treatment for end-stage non-alcoholic fatty liver disease (NAFLD) (related decompensated cirrhosis and/or hepatocellular carcinoma). The aim of our study was to evaluate the risk of disease recurrence after LT and the factors influencing it.

Method

This retrospective multicenter study included adults transplanted for NAFLD cirrhosis between 2000 and 2019 in 20 participating French-speaking centers. Disease recurrence (steatosis, steatohepatitis and fibrosis) was diagnosed from liver graft biopsies.

Results

We analyzed 150 patients with at least one graft liver biopsy available ≥6 months after transplantation, among 361 patients transplanted for NAFLD. The median (IQR) age at LT was 61.3 (54.4-64.6) years. The median follow-up after LT was 4.7 (2.8-8.1) years. The cumulative recurrence rates of steatosis and steatohepatitis at 5 years were 80.0% and 60.3%, respectively. Significant risk factors for steatohepatitis recurrence in multivariate analysis were recipient age at LT <65 years (odds ratio [OR] 4.214; p = 0.044), high-density lipoprotein-cholesterol <1.15 mmol/L after LT (OR 3.463; p = 0.013) and grade ≥2 steatosis on the graft at 1 year after LT (OR 10.196; p = 0.001). The cumulative incidence of advanced fibrosis (F3-F4) was 20.0% at 5 years after LT and significant risk factors from multivariate analysis were metabolic syndrome before LT (OR 8.550; p = 0.038), long-term use of cyclosporine (OR 11.388; p = 0.031) and grade ≥2 steatosis at 1 year after LT (OR 10.720; p = 0.049). No re-LT was performed for NAFLD cirrhosis recurrence.

Conclusion

Our results strongly suggest that recurrence of initial disease after LT for NAFLD is inevitable and progressive in a large proportion of patients; the means to prevent it remain to be further evaluated.

Impact and implications

Non-alcoholic fatty liver disease (NAFLD) is a growing indication for liver transplantation, but the analysis of disease recurrence, based on graft liver biopsies, has been poorly studied. Cumulative incidences of steatosis, steatohepatitis and NAFLD-related significant fibrosis recurrence at 5 years were 85.0%, 60.3% and 48.0%, respectively. Grade ≥2 steatosis on graft biopsy at 1 year (present in 25% of patients) is highly predictive of recurrence of steatohepatitis and advanced fibrosis: bariatric surgery should be discussed in these patients specifically.

Metabolic mechanisms for and treatment of NAFLD or NASH occurring after liver transplantation

The rising tide of non-alcoholic fatty liver disease (NAFLD) associated with the obesity epidemic is a major health concern worldwide. NAFLD - specifically its more advanced form, non-alcoholic steatohepatitis (NASH)-related cirrhosis - is now the fastest growing indication for liver transplantation in the USA and Europe. Although the short-term and mid-term overall survival rates of patients who receive a liver transplant for NASH-related cirrhosis are essentially similar to those of patients who receive a transplant for other liver indications, recipients with NASH-related cirrhosis have an increased risk of waiting-list mortality and of developing recurrent liver disease and cardiometabolic complications in the longer term after liver transplantation. This Review provides a brief overview of the epidemiology of NAFLD and NASH and the occurrence of NAFLD or NASH in patients after liver transplantation for NASH and other liver indications. It also discusses the putative metabolic mechanisms underlying the emergence of NAFLD or NASH after liver transplantation as well as optimal therapeutic approaches for recipients of liver transplants, including the management of cardiometabolic comorbidities, tailored immunosuppression, lifestyle changes and pharmacotherapy for NAFLD.

Growing challenge of post-liver transplantation non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) is one of the leading causes of chronic liver disease, cirrhosis, and hepatocellular carcinoma worldwide, with an estimated prevalence of 25%. Post-liver transplantation (LT) recurrent or de novo hepatic steatosis is a common complication in recipients, irrespective of transplantation indication. Risk factors for graft steatosis mainly include obesity, immunosuppression, donor steatosis, and genetic factors. Liver transplant recipients are at high risk of developing insulin resistance, new-onset diabetes, and post-transplantation metabolic syndrome that is highly associated with immunosuppressive treatment. Post-LT NAFLD is often underdiagnosed due to the poor sensitivity of most routine imaging methods. The gold standard for the diagnosis of hepatic steatosis is liver biopsy, which is, however, limited to more complex cases due to its invasive nature. There is no approved pharmacotherapy in NAFLD. Lifestyle modification remains the cornerstone in NAFLD treatment. Other treatment strategies in post-LT NAFLD include lifestyle modifications, pharmacotherapy, bariatric surgery, and tailored immunosuppression. However, these approaches originate from recommendations in the general population, as there is scarce data regarding the safety and efficacy of current management strategies for NAFLD in liver transplant patients. Future prospective studies are required to achieve tailored treatment for these patients.

Nonalcoholic Fatty Liver Disease in Living Donor Liver Transplant Recipients: A Histology-Based Study

Background

Recurrent or de novo nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH) are common after liver transplantation (LT) and may be associated with rapid progression to fibrosis; however, there is limited data in this regard after living donor liver transplantation (LDLT).

Material and methods

This is a retrospective study at a high volume LDLT center of all liver biopsies performed in patients with post-transplant NAFLD diagnosed on ultrasound of the abdomen. Liver biopsy was indicated for raised transaminases and/or high liver stiffness on TE. The association between these prebiopsy parameters and inflammation and fibrosis on histology was analyzed. Data are shown as mean ± standard deviation or median (25-75 interquartile range).

Results

The study cohort consisted of 31 males and 3 females, aged 43 ± 10 years. The LT to liver biopsy interval was 44 (28-68) months. The prebiopsy AST and ALT were 71 (38-119) and 66 (50-156), respectively. The histology suggested no nonalcoholic steatohepatitis (NASH) in 7 (20%), borderline NASH in 15 (44%), and NASH in 12 (35%) patients. A total of 15 patients (44%) had stage 1 or stage 2 fibrosis. The proportion of patients having fibrosis was significantly higher in patients with NASH (83%) compared to patients with borderline NASH (33%) or no NASH (none had fibrosis, P = 0.001). Among 18 patients who underwent TE (on FibroScan), liver stiffness was significantly higher in patients with fibrosis [18.1 (9.7-22.5)] than in those without fibrosis [9.7 (4.0-12.7); P = 0.043].

Conclusion

Over a third of the LDLT recipients with post-transplant NAFLD developed NASH, and nearly half, borderline NASH 3-5 years after transplant. Most with established NASH also had fibrosis on histology. Prevention of risk factors and early diagnosis is warranted in these patients.

Clinicopathologic features of de novo non-alcoholic steatohepatitis in the post-transplant setting

BACKGROUND

Non-alcoholic steatohepatitis (NASH) has become an increasingly recognized problem in patients after orthotopic liver transplant. The aims of this study were to compare the clinicopathologic features of recurrent and de novo NASH.

METHODS

From 1995 to 2016, we performed a retrospective review of patients with a histological diagnosis of non-alcoholic steatohepatitis made more than 6 months after liver transplant at University of California, San Francisco. The cases were categorized into de novo (n = 19) or recurrent steatohepatitis (n = 37).

RESULTS

Hepatitis C virus (HCV) infection-related cirrhosis was the most common etiology of transplantation in de novo NASH (78% of cases, n = 29). There was no difference in glycogenosis or presence of grade 3 steatosis. More recurrent NASH biopsies had small ballooned hepatocytes (62.5% of cases) compared to de novo NASH (26.7%) (p = 0.03), and were less likely to show prominent portal inflammation (5% versus 40.5%, p = 0.0049). The diagnosis of recurrent NASH was made significantly sooner after transplantation than the diagnosis of de novo NASH (2.8 years versus 4.8 years, p = 0.02).

CONCLUSIONS

Overall, our results support that recurrent NASH demonstrates distinct clinicopathologic features compared to de novo NASH arising in the post-transplant setting.

Management of Patients With Non-alcoholic Steatohepatitis Undergoing Liver Transplantation: Considerations for the Anesthesiologist

Non-alcoholic fatty liver disease (NAFLD) currently affects more than 25% of the world population and is rising. NAFLD can progress to non-alcoholic steatohepatitis that is associated with hepatic inflammation and fibrosis and can result in cirrhosis with subsequent liver failure. Non-alcoholic steatohepatitis (NASH) has now emerged as one of the leading etiologies for a liver transplant among adults in the United States. Given the rising incidence of liver transplants in patients with NASH-related cirrhosis, it is essential for anesthesiologists to be familiar with this condition as well as with NASH-related comorbidities and perioperative complications. Not only is NASH linked to metabolic syndrome, but it also is independently associated with cardiovascular disease, renal and thyroid dysfunction, obstructive sleep apnea (OSA), and a hypercoagulable state. The association with these conditions can affect the perioperative outcome of these patients, particularly because of increased mortality from major adverse cardiovascular events and sepsis. In order to decrease the perioperative morbidity and mortality of patients with NASH undergoing a liver transplant, a multidisciplinary approach to their perioperative management is essential, along with careful preoperative evaluation and aggressive intraoperative and postoperative monitoring. The focus of this review article is to provide a comprehensive overview of challenges associated with liver transplants in patients with NASH and to provide suggestions for appropriate patient selection and perioperative management.

Predictors of solid extra-hepatic non-skin cancer in liver transplant recipients and analysis of survival: A long-term follow-up study

INTRODUCTION AND OBJECTIVES

De novo malignancies represent an important cause of death for liver transplant recipients. Our aim was to analyze predictors of extra-hepatic non-skin cancer (ESNSC) and the impact of ESNSC on the long-term outcome.

PATIENTS

We examined data from patients transplanted between 2000 and 2005 and followed-up in five Italian transplant clinics with a retrospective observational cohort study. Cox Regression was performed to identify predictors of ESNSC. A 1:2 cohort sub-study was developed to analyze the impact of ESNSC on 10-year survival.

RESULTS

We analyzed data from 367 subjects (median follow-up: 15 years). Patients with ESNSC (n = 47) more often developed post-LT diabetes mellitus (DM) (57.4% versus 35,9%, p = 0.004). At multivariate analysis, post-LT DM independently predicted ESNSC (HR 1.929, CI 1.029-3.616, p = 0.040). Recipients with ESNSC showed a lower 10-year survival than matched controls (46,8% versus 68,1%, p = 0.023).

CONCLUSIONS

Post-LT DM seems to be a relevant risk factor for post-LT ESNSC. ESNSC could have a noteworthy impact on the long-term survival of LT recipients.

Prevalence of fatty liver disease after liver transplantation and risk factors for recipients and donors

INTRODUCTION AND OBJECTIVES

Fatty liver disease (FLD) may develop in liver transplant recipients. We investigated the recipient and donor risk factors for FLD development after liver transplantation (LT).

METHODS

A total of 108 liver transplant recipients (54 men [50.0%]; median age, 52 [20-68] years) treated from 2011-2020 was enrolled. Three recipients died at < 3 months as a result of infection or blood flow impairment, and were excluded from the long-term FLD study. On evaluation of 88 prospective living donors, fatty liver was observed in 21. The prevalence and risk factors for FLD and survival were evaluated.

RESULTS

After LT, 28 of 105 recipients (26.7%) developed FLD. FLD was more common in patients with a high body mass index (BMI) and dyslipidemia (both p < 0.01), primary nonalcoholic steatohepatitis (p = 0.02), after living-donor LT (p = 0.03) and everolimus (EVL) use (p = 0.08). Factors predictive of FLD included EVL use and a high BMI (hazard ratios = 3.00 and 1.34; p = 0.05 and p < 0.01, respectively). Sixteen donors lost 6.5 kg (range: 2.0-16.0 kg) of body weight prior to LT. However, there were no cases of primary non-function, which did not affect the FLD prevalence. Development of FLD did not have a negative impact on LT outcome; the 5-year survival rate was 92.6%.

CONCLUSIONS

Recipient factors were more important than donor factors for FLD onset after LT.

Impact of Donor and Recipient Clinical Characteristics and Hepatic Histology on Steatosis/Fibrosis Following Liver Transplantation

BACKGROUND

Deceased donor and recipient predictors of posttransplant steatosis/steatohepatitis and fibrosis are not well known. Our aim was to evaluate the prevalence and assess donor and recipient predictors of steatosis, steatohepatitis, and fibrosis in liver transplantation recipients.

METHODS

Using the immune tolerance network A-WISH multicenter study (NCT00135694), donor and recipient demographic and clinical features were collected. Liver biopsies were taken from the donor liver at transplant, and from recipients per protocol and for-cause (ie, abnormal transaminases and to rule out rejection) and were interpreted by a central pathologist.

RESULTS

One hundred eighty-three paired donor/recipients liver biopsies at the time of transplant and posttransplant follow-up (median time 582 d; average time to last biopsies was 704 d [SD ± 402 d]) were analyzed. Donor steatosis did not influence recipient steatosis or fibrosis. Ten of 183 recipients had steatohepatitis on the last biopsy. Recipient body mass index at the time of liver biopsy was the most influential factor associated with posttransplant steatosis. Both donor and recipient metabolic syndrome features were not associated with graft steatosis. Untreated hepatitis C viral (HCV) infection was the most influential factor associated with the development of allograft fibrosis.

CONCLUSIONS

In a large experience evaluating paired donor and recipient characteristics, recipient body mass index at the time of liver biopsy was most significantly associated with posttransplant steatosis. Untreated HCV etiology influenced graft fibrosis. Thus relative to untreated HCV, hepatic fibrosis in those with steatosis/steatohepatitis is less common though long-term follow-up is needed to determine the course of posttransplant fibrosis. Emphasis on recipient weight control is essential.

How will NAFLD change the liver transplant landscape in the 2020s?

Liver steatosis is the hepatic manifestation of the metabolic syndrome, and is now the leading cause of chronic liver disease worldwide. The treatment of metabolic cirrhosis with liver failure and/or hepatocellular carcinoma is liver transplantation (LT). During the past decade, metabolic cirrhosis represented an increasing cause for LT, especially in the United States. At listing, patients with metabolic cirrhosis are older, with numerous cardiovascular (CV) and renal comorbidities, and this requires multidisciplinary pre-transplant assessment. After LT, 5-year survival is similar to other indications. The leading causes of death are infectious, cancers and CV. The recurrence of the initial disease is very frequent, and a significant part of the patients progress towards graft cirrhosis. No specific immunosuppressive regimen is recommended, but the toxicity profiles must probably be taken into account. In these patients, the only etiological treatment is that of obesity, in the absence of specific therapy for non-alcoholic steatohepatitis. The place of bariatric surgery has to be defined, probably sleeve gastrectomy, in a stable patient, 6-12 months after LT.

De novo and recurrence of metabolic dysfunction-associated fatty liver disease after liver transplantation

Metabolic dysfunction-associated fatty liver disease (MAFLD) is a new acronym adopted from the consensus of international experts. Given the increasing prevalence of MAFLD in pre-transplant settings, de novo and recurrent graft steatosis/MAFLD are common in post-transplant settings. The impact of graft steatosis on long-term outcomes is unclear. The current knowledge of incidence rate, risk factors, diagnosis, long-term outcomes, and management of graft steatosis (both de novo and recurrent) is discussed in this review.

Utility of Metabolomic Biomarkers to Identify Nonalcoholic Fatty Liver Disease in Liver Transplant Recipients

Nonalcoholic fatty liver disease (NAFLD) is a rising indication for liver transplantation (LT). Identification of NAFLD recurrence and those at risk for more progressive disease after LT remains elusive as the diagnosis requires biopsy, which is invasive and impractical for serial monitoring. We therefore aimed to identify metabolites in the blood associated with recurrent NAFLD that could potentially be used for detection and monitoring.

A weight regain of 1.5 kg or more and lack of exercise are associated with nonalcoholic fatty liver disease recurrence in men

The importance of maintaining the remission of nonalcoholic fatty liver disease (NAFLD) has been overlooked. Here we aimed to clarify factors causing NAFLD recurrence. In this retrospective cohort study over 10.8 ± 5.4 years, we investigated 1260 male health check-up participants diagnosed with NAFLD who achieved remission. The data were compared between the maintained remission and recurrence group. Among all participants, 618 (49.0%) showed NAFLD recurrence at the last visit. Participants in the maintained remission group continued to lose weight (72.7 ± 9.1, 68.7 ± 8.5 and 68.2 ± 8.9 kg), whereas those in the recurrence group lost and regained weight (72.9 ± 9.9, 69.7 ± 9.3 and 73.0 ± 10.4 kg). Receiver operating characteristic curve analysis showed a weight regain of + 1.5 kg as the cutoff value for recurrence. The proportion of regular exercisers at the last visit was 34.6% in the maintained remission group and 24.5% in the recurrence group (p < 0.0001). Multivariable analysis revealed the amount of weight regain (in 1 kg increments; adjusted odds ratio, 1.29; 95% confidence interval, 1.24–1.34) and regular exercise at the last visit (adjusted odds ratio, 0.67; 95% confidence interval, 0.55–0.89) were independently associated with recurrence. These findings demonstrate a weight regain of 1.5 kg or more and lack of exercise were associated with NAFLD recurrence.

New-onset cardiovascular risk factors following liver transplantation: A cohort analysis in Singapore

INTRODUCTION

The aims of this study were to establish weight change, incidence of non-alcoholic fatty liver disease (NAFLD) and cardiovascular risk factors (CvRF) in liver transplant recipients (LTRs).

METHODS

Eighty-three patients whose mean (standard deviation [SD]) age was 55.6 (8.4) years (median follow-up 73 months) and who underwent their first liver transplantation (LT) at Singapore General Hospital between February 2006 and March 2017 were included in the study. Anthropometric, clinical and demographic data were collected retrospectively from patients' medical records. Diabetes mellitus (DM), hyperlipidaemia and hypertension were regarded as CvRF.

RESULTS

Compared to baseline, mean (SD) body weight decreased significantly at 1 month post-LT (60.8kg [11.9] versus 64.3kg [13.7], P<0.001). There was a gradual recovery of body weight thereafter, increasing significantly at year 2 (64.3kg [12.3] vs 61.5kg [13.7], P<0.001) until year 5 (66.9kg [12.4] vs 62.2kg [13.9], P<0.001), respectively. The prevalence of CvRF was significantly higher post-LT. NAFLD occurred in 25.3% of LTRs and it was significantly associated with post-LT DM and hyperlipidaemia.

CONCLUSION

CvRF increased significantly post-LT, and NAFLD occurred in 25.3% of LTRs. Body weight dropped drastically within the first month post-LT, which then returned to baseline level just before the end of first year. This novel finding suggests that nutritional intervention needs to be tailored and individualised, based on events and time from transplant. Although long-term obesity is a significant problem, aggressive oral or enteral nutritional supplements take precedence in the early and immediate post-LT period, while interventions targeted at metabolic syndrome become necessary after the first year.

Nonalcoholic Fatty Liver Disease after Liver Transplant

Nonalcoholic fatty liver disease (NAFLD) is one of the most common causes of chronic liver disease in the world. The rising prevalence of nonalcoholic steatohepatitis (NASH) has led to a 170% increase in NASH cirrhosis as the listing indication for liver transplantation from 2004 to 2013. As of 2018, NASH has overtaken hepatitis C as an indication for liver transplantation in the USA. After liver transplantation, the allograft often develops recurrent NAFLD among patients with known NASH cirrhosis. In addition to recurrent disease, de novo NAFLD has been reported in patients with other indications for liver transplantation. In this review, we will discuss the risk factors associated with recurrent and de novo NAFLD, natural course of the disease, and management strategies after liver transplantation.

Noninvasive markers of liver steatosis and fibrosis after liver transplantation - Where do we stand?

In the last two decades, advances in immunosuppressive regimens have led to fewer complications of acute rejection crisis and consequently improved short-term graft and patient survival. In parallel with this great success, long-term post-transplantation complications have become a focus of interest of doctors engaged in transplant medicine. Metabolic syndrome (MetS) and its individual components, namely, obesity, dyslipidemia, diabetes, and hypertension, often develop in the post-transplant setting and are associated with immuno-suppressive therapy. Nonalcoholic fatty liver disease (NAFLD) is closely related to MetS and its individual components and is the liver manifestation of MetS. Therefore, it is not surprising that MetS and its individual components are associated with recurrent or "de novo" NAFLD after liver transplantation (LT). Fibrosis of the graft is one of the main determinants of overall morbidity and mortality in the post-LT period. In the assessment of post-LT steatosis and fibrosis, we have biochemical markers, imaging methods and liver biopsy. Because of the significant economic burden of post-LT steatosis and fibrosis and its potential consequences, there is an unmet need for noninvasive methods that are efficient and cost-effective. Biochemical scores can overestimate fibrosis and are not a good method for fibrosis evaluation in liver transplant recipients due to frequent post-LT thrombocytopenia. Transient elastography with controlled attenuation parameter is a promising noninvasive method for steatosis and fibrosis. In this review, we will specifically focus on the evaluation of steatosis and fibrosis in the post-LT setting in the context of de novo or recurrent NAFLD.

Long-term Management of the Adult Liver Transplantation Recipients

The survival of liver transplantation (LT) recipients has been improved remarkably in short-term. The major causes of mortality in long-term include nonimmunological causes such as cardiovascular, de novo malignancy, chronic kidney disease, and recurrence of primary disease. Rejection-related mortality is rare in the long-term after LT. We discuss nonrejection causes of long-term morbidity/mortality, risk factors, and management strategies in LT recipients. In addition, we discuss osteoporosis, contraception, and pregnancy in LT recipients.

De-novo nonalcoholic fatty liver disease at 5 years after liver transplantation: prevalence and predictive factors

BACKGROUND AND AIMS

Nonalcoholic fatty liver disease (NAFLD) is a long-term complication after liver transplantation. Our aims were to determine de-novo-NAFLD at 5-year post-liver transplantation and identify predictive risk factors.

METHODS

This was a retrospective analysis of de-novo-NAFLD at 5-year post-liver transplantation. NAFLD was defined as the radiological evidence of steatosis. Data from transplanted patients between November 2001 and May 2014 were collected. Noninvasive fibrosis scores were calculated. Predictors of de-novo NAFLD and survival were assessed by multivariate analyses and Kaplan-Meier method.

RESULTS

A total of 252 liver transplantations were evaluated after applying exclusion criteria, (78.6% men) with 54.9 years old (SD ± 9.5). Prevalence of de-novo NAFLD at 5-year post-liver transplantation was 36.1%. Cardiovascular events were presented in 19.88% and 23.08% of non-NAFLD and NAFLD patients, (P = 0.58). On multivariate analysis, male sex (OR, 5.40; P = 0.001), obesity (OR, 3.72; P = 0.017), metabolic syndrome (OR, 4.69; P < 0.001) and de-novo diabetes (OR, 2.79; P = 0.018), were predictive. Significant fibrosis (≥F2) was presented in 58-86%. The mean survival in NAFLD and control group was 166.3 and 173.6 months, respectively (P = 0 0.50).

CONCLUSION

De-novo NAFLD at fifth-year post-liver transplantation is frequently and associated with cardiovascular comorbidity. Male sex, obesity, de-novo diabetes and metabolic syndrome were factors associated with de-novo NAFLD. A significant proportion of patients had advanced fibrosis. This group trends toward worse patients' survival.

Clinical and Genetic Risk Factors of Recurrent Nonalcoholic Fatty Liver Disease After Liver Transplantation

INTRODUCTION

Nonalcoholic fatty liver disease (NAFLD) has been increasingly reported among recipients of liver transplantation (LT). We aimed to identify clinical and genetic risk factors responsible for the development of early recurrent NAFLD in nonalcoholic steatohepatitis transplant recipients.

METHODS

Forty-six total single nucleotide polymorphisms with known association with NAFLD were tested among both recipient and donor liver samples in 66 LT recipients with nonalcoholic steatohepatitis to characterize influences on NAFLD recurrence at ∼1 year post-LT (median interval from LT to biopsy: 377 days).

RESULTS

Recurrent NAFLD was identified in 43 (65.2%) patients, 20 (30.3%) with mild recurrence, and 23 (34.8%) with moderate to severe NAFLD. On adjusted analysis, change in the body mass index (BMI) (ΔBMI) was significantly associated with NAFLD recurrence, whereas post-LT diabetes mellitus was associated with increased severity of NAFLD recurrence. ADIPOR1 rs10920533 in the recipient was associated with increased risk of moderate to severe NAFLD recurrence, whereas the minor allele of SOD2 rs4880 in the recipient was associated with reduced risk. Similar reduced risk was noted in the presence of donor SOD2 rs4880 and HSD17B13 rs6834314 polymorphism.

DISCUSSION

Increased BMI post-LT is strongly associated with NAFLD recurrence, whereas post-LT diabetes mellitus was associated with increased severity of NAFLD recurrence. Both donor and recipient SOD2 rs4880 and donor HSD17B13 rs6834314 single nucleotide polymorphisms may be associated with reduced risk of early NAFLD recurrence, whereas presence of the minor allele form of ADIPOR1 rs10920533 in the recipient is associated with increased severity NAFLD recurrence.

Cardiovascular involvement after liver transplantation: role of non-alcoholic fatty liver disease and non-alcoholic steatohepatitis

Patients submitted to liver transplantation (LT) are exposed to high risk of cardiovascular (CV) complications which are the main determinants of both short-term and long-term morbidity and mortality in LT. Non-alcoholic fatty liver disease (NAFLD) is a very frequent condition in general population and is associated with a high risk of cardiovascular disease (CVD) which represents the first cause of death of these patients. NAFLD is predicted to become the first indication to LT and nowadays is also frequently detected in patients submitted to LT for other indications. Thus, the risk of CVD in patients submitted to LT is forecasted to increase in the next years. In this review the extent of CV involvement in patients submitted to LT and the role of NAFLD, either recurring after transplantation or as de novo presentation, in increasing CV risk is analysed. The risk of developing metabolic alterations, including diabetes, hypertension, dyslipidemia and weight gain, all manifestations of metabolic syndrome, occurring in the first months after LT, is depicted. The different presentations of cardiac involvement, represented by early atherosclerosis, coronary artery disease, heart failure and arrhythmias in patients with NAFLD submitted to LT is described. In addition, the tools to detect cardiac alterations either before or after LT is reported providing the possibility for an early diagnosis of CVD and an early therapy able to reduce morbidity and mortality for these diseases. The need for long-term concerted multidisciplinary activity with dietary counseling and exercise combined with drug treatment of all manifestations of metabolic syndrome is emphasized.

Hepatocellular carcinoma in non-alcoholic fatty liver disease-a review of an emerging challenge facing clinicians

Importance

Non-alcoholic fatty liver disease (NAFLD) is a rapidly growing cause of chronic liver disease and is becoming a leading cause of hepatocellular carcinoma (HCC) in many developed countries. This presents major challenges for the surveillance, diagnosis and treatment of HCC.

Objective

To discuss the clinical challenges faced by clinicians in managing the rising number of NAFLD-HCC cases.

Evidence Review

MEDLINE, PubMed and Embase databases were searched using the keywords; NAFLD, HCC, surveillance, hepatectomy, liver transplantation, percutaneous ablation, transarterial chemoembolization (TACE), selective internal radiotherapy treatment (SIRT) and sorafenib. Relevant clinical studies were included.

Findings

Current HCC surveillance programmes are inadequate because they only screen for HCC in patients with cirrhosis, whereas in NAFLD a significant proportion of HCC develops in the absence of cirrhosis. Consequently NAFLD patients often present with a more advanced stage of HCC, with a poorer prognosis. NAFLD-HCC patients also tend to be older and to have more co-morbidities compared to HCC of other etiologies. This limits the use of curative treatments such as liver resection and orthotopic liver transplantation (OLT). Evidence suggests that although NAFLD-HCC patients who undergo liver resection or OLT have worse perioperative and short-term outcomes, overall long-term survival is comparable to HCC of other etiologies. This highlights the importance of careful patient selection, pre-habilitation and perioperative planning for NAFLD-HCC patients being considered for surgical treatment. Careful consideration is also important for non-surgical treatments, although the evidence supporting treatment selection is frequently lacking, as these patients tend to be poorly represented in clinical trials. Locoregional therapies such as percutaneous ablation and TACE may be less well tolerated and less effective in NAFLD patients with obesity or diabetes. The tyrosine kinase inhibitor sorafenib may also be less effective.

Conclusions and Relevance

This review highlights how international guidelines, for which NAFLD traditionally has made up a small part of the evidence base, may not be appropriate for all NAFLD-HCC patients. Future guidelines need to reflect the changing landscape of HCC, by making specific recommendations for the management of NAFLD-HCC.

Obesity Management of Liver Transplant Waitlist Candidates and Recipients

Obesity is increasing in prevalence in liver transplant candidates and recipients. The rise in liver transplantation for nonalcoholic steatohepatitis reflects this increase. Management of obesity in liver transplant candidates can be challenging due to the presence of decompensated cirrhosis and sarcopenia. Obesity may increase peritransplant morbidity but does not have an impact on long-term post-transplant survival. Bariatric surgery may be a feasible option in select patients before, during, or after liver transplantation. Use of weight loss drugs and/or endoscopic therapies for obesity management ultimately may play a role in liver transplant patients, but more research is needed to determine safety.

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.

Approach to prevention of non-alcoholic fatty liver disease after liver transplantation

Non-alcoholic fatty liver disease (NAFLD) is one of the most common causes of liver disease and non-alcoholic steatohepatitis (NASH) related cirrhosis is third common indication for liver transplantation (LT). Patients who have NASH related cirrhosis and are candidates for LT often have multiple comorbidities. These comorbidities need to be addressed before and after transplantation as it affects overall survival. Like hepatitis B, hepatitis C, primary biliary cirrhosis, autoimmune hepatitis which recurs after transplantation, NASH also recurs after transplant however the impact of the recurrence on allograft and patient outcomes is unclear. Limited data suggests that it does not affect graft and patient survival. De novo NAFLD which is defined as occurrence of fatty liver in a patient who did not have fatty liver prior to LT can also occur in the allograft of patients transplanted for non-NAFLD liver disease. Obesity, hyperlipidemia, diabetes as well as steroid dose and duration after LT are common predictors of recurrence of NAFLD after transplantation. Studies on prevention and treatment of NASH in post-transplant patients are lacking. Prevention of weight gain, regular exercises, weight reducing surgery, limited steroid use or steroid free regimen have been tried with varying success. Future studies for the prevention of NAFLD/NASH are required especially in post liver transplant patient.

Association between obesity after liver transplantation and steatosis, inflammation, and fibrosis of the graft

BACKGROUND

Nonalcoholic steatohepatitis has become one of the leading causes of liver transplantation. The development of steatosis, as well as the link to inflammation and fibrosis, after transplantation remain poorly understood. The aim of this analysis was to evaluate the influence of obesity on histopathological changes of the graft during long-term follow-up.

METHODS

A total of 1494 longitudinal liver biopsies of 271 recipients were evaluated during a follow-up period of 5 to 10 years. Clinical and laboratory parameters as well as histopathological categories of steatosis, inflammation, and fibrosis were explored by routine protocol biopsies.

RESULTS

The BMI and prevalence of diabetes mellitus significantly increased after transplantation (P < .01). Diabetes and de novo obesity were significantly associated with the degree of graft steatosis. There was no correlation between former steatosis and inflammation or fibrosis. Inflammation was a precursor of fibrosis, and fibrosis increased over the first 3 years (P < .01). No severe graft dysfunction was observed.

CONCLUSION

Obesity and diabetes mellitus correlated with higher grades of steatosis and de novo steatosis after transplantation. Metabolic syndrome must be considered as a serious post-transplant complication that can cause histopathological alteration. However, the progress from steatosis to steatohepatitis is not as common as expected.

Changing trends of liver transplantation and mortality from non-alcoholic fatty liver disease

The rising tide of non-alcoholic fatty liver disease (NAFLD) associated with the obesity epidemic is a major international health concern. NAFLD is the leading global cause of liver disease with an estimated prevalence of 25% and is the fastest growing indication for liver transplantation (LT). The presence and severity of liver fibrosis is the only histologic predictor of clinical outcomes in this group. NAFLD poses several challenges in the peri-transplant setting including the management of multiple metabolic co-morbidities, post-transplant obesity and cardiovascular risk. However, post-LT outcomes in well-selected NAFLD patients appear similar to non-NAFLD indications, including in the setting of hepatocellular carcinoma (HCC). The rising prevalence of NAFLD may impact potential liver graft donors, which may in-turn adversely affect post-LT outcomes. This review outlines the current epidemiology, natural history and outcomes of NAFLD with a focus on pre- and post-liver transplant settings.

Donor PNPLA3 and TM6SF2 Variant Alleles Confer Additive Risks for Graft Steatosis After Liver Transplantation

BACKGROUND

The rs58542926 polymorphism in transmembrane 6 superfamily member 2 (TM6SF2) is a genetic factor predisposing to nonalcoholic fatty liver disease. We aimed to explore the effect of recipient and donor TM6SF2 rs58542926 genotypes on liver graft fat content after liver transplantation.

METHODS

Steatosis was evaluated in liver biopsies from 268 adult recipients. The influence of recipient and donor TM6SF2 genotypes, patatin-like phospholipase domain-containing 3 (PNPLA3) rs738409 genotypes, and nongenetic factors on the steatosis grade assessed 6-30 months after transplantation was analyzed by ordinal logistic regression.

RESULTS

The presence of the TM6SF2 c.499A allele in the donor (P = 0.014), PNPLA3 c.444G allele in the donor (P < 0.001), posttransplant body mass index (P < 0.001), and serum triglycerides (P = 0.047) independently predicted increased liver fat content on multivariable analysis, whereas noncirrhotic liver disease, as an indication for liver transplantation, was associated with lower risk of steatosis (P = 0.003). The effects of the donor TM6SF2 A and PNPLA3 G alleles were additive, with an odds ratio of 4.90 (95% confidence interval, 2.01-13.00; P < 0.001), when both minor alleles were present compared with an odds ratio of 2.22 (95% confidence interval, 1.42-3.61; P = 0.002) when only one of these alleles was present.

CONCLUSIONS

The donor TM6SF2 c.499A allele is an independent risk factor of liver graft steatosis after liver transplantation that is additive to the effects of donor PNPLA3 c.444G allele.

Pre-transplant diabetes predicts atherosclerotic vascular events and cardiovascular mortality in liver transplant recipients: a long-term follow-up study

Background Early after surgery, liver transplant (LT) recipients often develop weight gain. Metabolic disorders and cardiovascular disease represent main drivers of morbidity and mortality. Our aim was to identify predictors of atherosclerotic vascular events (AVE) and to assess the impact of AVE on the long-term outcome. Methods We retrospectively analyzed data from patients transplanted between 2000 and 2005 and followed-up in five Italian transplant clinics. Cox Regression analysis was performed to identify predictors of AVE, global mortality, and cardiovascular mortality. Survival analysis was performed using the Kaplan-Meier method. Results We analyzed data from 367 subjects during a median follow-up of 14 years. Thirty-seven post-LT AVE were registered. Patients with AVE more frequently showed pre-LT diabetes mellitus (DM) (48.6 vs 13.9%, p=0.000). In the post-LT period, patients with AVE satisfied criteria of metabolic syndrome in 83.8% vs. 36.7% of subjects without AVE (p=0.000). At multivariate analysis, pre-LT DM independently predicted AVE (HR 2.250, CI 4.848-10.440, p=0.038). Moreover, both pre-LT DM and AVE strongly predicted cardiovascular mortality (HR 5.418, CI 1.060-29.183, p=0.049, and HR 86.097, CI 9.510-779.480, p=0.000, respectively). Conclusions Pre-LT DM is the main risk factor for post-LT AVE. Pre-LT DM and post-LT AVE are strong, long-term predictors of cardiovascular mortality. Patients with pre-LT DM should obtain a personalized follow-up for prevention or early diagnosis of AVE.

Non-alcoholic fatty liver disease: A review with clinical and pathological correlation

Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease in North America and Europe, with increasing prevalence in other regions of the world. Its spectrum encompass steatosis, non-alcoholic steatohepatitis (NASH), fibrosis and cirrhosis. It is considered as the manifestation of metabolic syndrome in liver, and its development and progression is influenced by complex interaction of environmental and genetic factors. In this review we discuss the histopathological features, differential diagnoses, and the commonly used grading and staging systems of NAFLD. NAFLD associated with other diseases, histological changes after therapeutic intervention and recurrence or occurrence of NAFLD after liver transplantation are also addressed.

Incidence and Risks for Nonalcoholic Fatty Liver Disease and Steatohepatitis Post-liver Transplant: Systematic Review and Meta-analysis

BACKGROUND

The true incidence and unique risk factors for recurrent and de novo nonalcoholic fatty liver (NAFLD) and nonalcoholic steatohepatitis (NASH) post-liver transplant (LT) remain poorly characterized. We aimed to identify the incidence and risk factors for recurrent and de novo NAFLD/NASH post-LT.

METHODS

MEDLINE via PubMed, Embase, Scopus, and CINAHL were searched for studies from 2000 to 2018. Risk of bias was adjudicated using the Newcastle-Ottawa Scale.

RESULTS

Seventeen studies representing 2378 patients were included. All were retrospective analyses of patients with post-LT liver biopsies, with the exception of 2 studies that used imaging for outcome assessment. Seven studies evaluated occurrence of recurrent NAFLD/NASH, 3 evaluated de novo occurrence, and 7 evaluated both recurrent and de novo. In studies at generally high or moderate risk of bias, mean 1-, 3-, and ≥5-year incidence rates may be 59%, 57%, and 82% for recurrent NAFLD; 67%, 40%, and 78% for de novo NAFLD; 53%, 57.4%, and 38% for recurrent NASH; and 13%, 16%, and 17% for de novo NASH. Multivariate analysis demonstrated that post-LT body mass index (summarized odds ratio = 1.27) and hyperlipidemia were the most consistent predictors of outcomes.

CONCLUSIONS

There is low confidence in the incidence of recurrent and de novo NAFLD and NASH after LT due to study heterogeneity. Recurrent and de novo NAFLD may occur in over half of recipients as soon as 1 year after LT. NASH recurs in most patients after LT, whereas de novo NASH occurs rarely. NAFLD/NASH after LT is associated with metabolic risk factors.

Post-transplant diabetes mellitus and preexisting liver disease - a bidirectional relationship affecting treatment and management

Liver cirrhosis and diabetes mellitus (DM) are both common conditions with significant socioeconomic burden and impact on morbidity and mortality. A bidirectional relationship exists between DM and liver cirrhosis regarding both etiology and disease-related complications. Type 2 DM (T2DM) is a well-recognized risk factor for chronic liver disease and vice-versa, DM may develop as a complication of cirrhosis, irrespective of its etiology. Liver transplantation (LT) represents an important treatment option for patients with end-stage liver disease due to non-alcoholic fatty liver disease (NAFLD), which represents a hepatic manifestation of metabolic syndrome and a common complication of T2DM. The metabolic risk factors including immunosuppressive drugs, can contribute to persistent or de novo development of DM and NAFLD after LT. T2DM, obesity, cardiovascular morbidities and renal impairment, frequently associated with metabolic syndrome and NAFLD, may have negative impact on short and long-term outcomes following LT. The treatment of DM in the context of chronic liver disease and post-transplant is challenging, but new emerging therapies such as glucagon-like peptide-1 receptor agonists (GLP-1RAs) and sodium-glucose cotransporter 2 inhibitors (SGLT2i) targeting multiple mechanisms in the shared pathophysiology of disorders such as oxidative stress and chronic inflammation are a promising tool in future patient management.

The Utility of Assessing Liver Allograft Fibrosis and Steatosis Post-Liver Transplantation Using Transient Elastography With Controlled Attenuation Parameter

AIM

Allograft steatosis is an emerging concern after liver transplantation (LT). The use of transient elastography (TE) with controlled attenuation parameter (CAP) may facilitate early detection of and intervention for allograft steatosis. This study aimed to evaluate the prevalence and risk factors of allograft steatosis using TE and CAP.

METHODS

The presence of steatosis and severe steatosis were defined by CAP ≥222 and ≥290 dB/m, respectively. Demographics and clinical characteristics were compared between patients with and without severe steatosis. Regression analyses were performed to determine factors associated with severe steatosis.

RESULTS

Of 150 patients, 105 (70%) had steatosis while 40% of these had severe steatosis. Thirty-four (81.0%) patients with severe steatosis had normal alanine transaminase at the time of TE. In multivariable analyses, age at LT (odds ratio [OR] 1.05, 95% confidence interval [CI] 1.01-1.08), post-LT obesity (OR 5.34, 95% CI 1.53-18.65), and alcoholic liver disease (OR 12.86, 95% CI 2.24-73.74) were significant predictors of severe steatosis. Five patients underwent liver biopsies as a result of advance fibrosis seen on TE and were later diagnosed with chronic allograft rejection. Two of these patients had normal liver chemistries, and the remaining 3 had mild elevation of alkaline phosphatase.

CONCLUSION

Steatosis was present in 70% of patients who underwent TE after LT. Advanced age at LT, post-LT obesity, and alcoholic liver disease were significant predictors for severe steatosis. The majority of patients with severe steatosis had normal liver enzymes. TE should be considered as a screening modality for allograft steatosis and fibrosis even when liver chemistries are normal.