Impact of Nonmalignant Portal Vein Thrombosis in Transplant Recipients With Nonalcoholic Steatohepatitis

Predictors of portal vein thrombosis after splenectomy in patients with cirrhosis

BACKGROUND

Portal vein thrombosis (PVT) is a commonthsn complication after splenectomy in patients with cirrhosis. However, the predictors of postoperative PVT are not known.

AIM

To investigate the predictors of PVT after splenectomy in patient with cirrhosis.

METHODS

A total of 45 patients with cirrhosis who underwent splenectomy were consecutively enrolled from January 2017 to December 2018. The incidence of PVT at 1 months, 3 months, and 12 months after splenectomy in patients with cirrhosis was observed. The hematological indicators, biochemical and coagulation parameters, and imaging features were recorded at baseline and at each observation point. The univariable, multivariable, receiver operating characteristic curve and time-dependent curve analyses were performed.

RESULTS

The cumulative incidence of PVT was 40.0%, 46.6%, and 48.9% at 1 months, 3 months, and 12 months after splenectomy. Multivariable analysis showed that portal vein diameter (PVD) ≥ 14.5 mm and monthsdel‎ end-stage liver disease (MELD) score > 10 were independent predictors of PVT at 1 months, 3 months, and 12 months after splenectomy (P < 0.05). Time-dependent curve showed that the cumulative incidence of PVT was significantly different between patients with MELD score ≤ 10 and > 10 (P < 0.05). In addition, the cumulative incidence of PVT in the PVD ≥ 14.5 mm group was significantly higher than that in the PVD < 14.5 mm group (P < 0.05).

CONCLUSION

Wider PVD and MELD score > 10 were independent predictors of PVT at 1 months, 3 months, and 12 months after splenectomy in patient with cirrhosis.

Prevalence of portal vein thrombosis in non-alcoholic fatty liver disease: a meta-analysis of observational studies

Portal vein thrombosis (PVT) is a common complication of cirrhosis as a result of portal hypertension and modification in the hemostatic balance. Accumulating evidence now suggests that patients with non-alcoholic fatty liver disease (NAFLD), especially those with advanced forms, have an increased risk of PVT. Hence, we performed a meta-analysis of observational studies to estimate the overall prevalence of PVT in patients with NAFLD and its advanced forms compared with patients with advanced liver diseases from other etiologies. We systematically searched PubMed, Scopus and Web of Science databases from the inception date to December 30th 2022, using predefined keywords, to identify observational studies. Meta-analysis was performed using random-effects modeling. We included five observational studies for a total of 225,571 patients. Of these, 26,840 (11.9%) patients had NAFLD, whereas the PVT prevalence was 8.5% (n = 2,280). When compared with patients with advanced liver diseases from other etiologies, patients with NAFLD and its advanced forms had a higher risk of prevalent PVT (OR 1.34, 100% CI 1.07-1.67 p < 0,01). The between-study heterogeneity was substantial (I2 = 88%). This meta-analysis suggests that compared with patients with advanced liver diseases from other etiologies, patient with NAFLD and its advanced forms had a higher risk of prevalent PVT. Further research is required to understand the complex link between NAFLD/NASH and PVT development.

[Nonalcoholic fatty liver disease : Hepatic manifestations of metabolic syndrome]

Nonalcoholic fatty liver disease (NAFLD) is nowadays the leading cause of chronic liver disease worldwide and shows a strong association with the metabolic syndrome. The NAFLD is a systemic disease associated with a plethora of extrahepatic manifestations and comorbidities, such as type 2 diabetes, obesity and dyslipidemia. These extrahepatic disorders are related either to secondary effects of the associated obesity or to pathophysiological effects of insulin resistance in NAFLD. The three most common causes of the observed increased morbidity and mortality associated with NAFLD are cardiovascular diseases, liver diseases, such as cirrhosis, and cancer. In this overview, cardiovascular diseases, type 2 diabetes mellitus and chronic kidney diseases in connection with NAFLD are discussed as examples, as well as tumor entities, in particular colon cancer, lung diseases (obstructive sleep apnea), endocrine diseases (hypothyroidism) and systemic phenomena associated with NAFLD (e.g. iron overload and thrombophilia). In addition to focusing on the pathogenesis of these extrahepatic manifestations, the clinical implications are highlighted. So far there are no drugs approved for the indication NAFLD in Germany. The new NAFLD S2k guidelines offer a way out of the current "therapeutic nihilism". Diagnostic and therapeutic algorithms based on the metabolic comorbidities and the stage of fibrosis are designed with practical relevance and can be used in everyday medical practice. Therefore, clear basic measures and drug recommendations can be given for NAFLD depending on the comorbidities and stage of fibrosis.

Incident portal vein thrombosis in liver transplant recipients in New Zealand: Predictors of risk and validation of portal vein thrombosis risk index calculator

The risk of spontaneous portal vein thrombosis (PVT) is increased in patients on the waiting list for liver transplantation and increases perioperative risks. A predictive PVT risk-index (PVT-RI) calculator has been proposed to determine the risk of incident PVT. We performed a retrospective analysis on adult liver transplant recipients at the NZ Liver Transplant Unit between January 1998 and February 2020. Variables reviewed included age at listing and transplantation, wait time from listing to transplant, indication for listing, gender, ethnicity, etiology of liver disease, listing MELD score, hepatocellular carcinoma (HCC), moderate-to-severe ascites, hepatic encephalopathy (>grade 2), transjugular intrahepatic portosystemic shunt (TIPSS), spontaneous bacterial peritonitis (SBP), and diabetes. Incident PVT was determined by imaging of patients while on the waiting list and assessment at transplantation. A total of 553 out of 706 patients met the inclusion criteria. Of those 553, 18 (3.3%) patients had incident PVT. The PVT-RI calculator was not validated in our cohort with only one of those 18 (6%) patients having a score of >4.6 (high risk cut-off score). Longer waiting time for transplant and listing for liver failure rather than HCC were independent predictors of the risk of incident PVT. There was no statistically significant difference in the incidence of PVT in viral vs. non-viral and cholestatic vs. non-cholestatic etiology of chronic liver disease. Patients with longer waiting times on the transplant waiting list should be monitored regularly for PVT.

Predictors of patient survival following liver transplant in non-alcoholic steatohepatitis: A systematic review and meta-analysis

BACKGROUND

Non-alcoholic steatohepatitis (NASH) is the second-leading indication for liver transplantation (LT) worldwide and is projected to become the leading indication. Our study aimed to determine clinical variables that predict post-LT survival in NASH.

METHODS

A systematic review and meta-analysis was performed. On June 18, 2020 and April 28, 2022, Ovid MEDLINE ALL, Ovid Embase, Cochrane Database of Systematic Reviews, and Cochrane Central Register of Controlled Trials were searched. No date limits were applied. Inclusion criteria specified the type of study and our study's population/comparison and outcome/timepoints. Pediatric, animal, retransplantation-only, and studies classifying cryptogenic cirrhosis patients with body mass index (BMI) <30 as NASH were excluded. Studies with duplicate cohorts and missing information were excluded from the meta-analysis. Studies were appraised using the Newcastle-Ottawa Scale. This study was preregistered in PROSPERO (CRD42020196915).

FINDINGS

Out of 8583 studies identified, 25 studies were included in the systematic review, while 5 studies were included in the meta-analysis. Our quantitative review suggested that the following variables were predictive of post-LT NASH patient survival: recipient age, functional status, pre-LT hepatoma, model for end-stage liver disease (MELD) score, diabetes mellitus (DM), pre-LT dialysis, hepatic encephalopathy, portal vein thrombosis, hospitalization/ICU at LT, and year of LT. Predictors of graft survival included recipient age, BMI, pre-LT dialysis, and DM. Our pooled meta-analyses included five predictors of patient survival. Increased patient mortality was associated with older recipient age (HR=2·07, 95%CI: 1·71-2·50, I²=0, τ²=0, p=0·40) and pretransplant DM (HR=1·18, 95%CI: 1·08-1·28, I²=0, τ²=0, p=0·76).

INTERPRETATION

Our systematic review and meta-analysis aimed to synthesise predictive variables of mortality in LT NASH patients. Clinically, this might help to identify modifiable risk factors that can be optimized in the post-transplant setting to improve patient outcomes and optimises decision making in the resource-limited LT setting.

FUNDING

Toronto General and Western Hospital Foundation.

Pre-transplant portal vein thrombosis in non-alcoholic fatty liver disease patients-pathogenesis, risk factors, and implications on management

Along with the worldwide increase in obesity and metabolic syndrome, non-alcoholic fatty liver disease (NAFLD) and its more severe subset, non-alcoholic steatohepatitis (NASH), are on path to become the leading cause of liver transplantation in the United States. NAFLD, as well as obesity, create an inflammatory milieu via the release of adipocytokines. In turn, the inflammatory environment can trigger an increase in prothrombotic factors. Independent of inflammation, the severity of NASH is associated with a graded increase in hypercoagulability such as an increase in factor VIII, increase in plasminogen activator inhibitor-1, and decrease in protein C. Ultimately, this environment creates an increase in thrombotic risk, leading to higher rates of pre-transplant portal vein thrombosis (PVT) in patients with NASH cirrhosis vesus other causes of cirrhosis. Many studies have shown worse outcomes in liver transplant recipients with PVT as it complicates anastomotic reconstruction which can negatively affect portal blood supply needed for adequate liver functioning. Management and treatment of PVT is not standardized, but from a pharmacologic standpoint, multiple classes of anticoagulants have shown to be successful in recanalization of the portal vein and preventing recurrence of clot with minimal bleeding complications. The increasing prevalence of NASH cirrhosis and subsequent increase in PVT require further research for improved outcomes.

Evaluation of liver transplant candidates with non-alcoholic steatohepatitis

Non-alcoholic steatohepatitis (NASH) is anticipated to become the leading indication for liver transplantation (LT) in the United States in the near future. LT is indicated in patients with NASH-related cirrhosis who have medically refractory hepatic decompensation, synthetic dysfunction, and hepatocellular carcinoma (HCC) meeting certain criteria. The objective of LT evaluation is to determine which patient will derive the most benefit from LT with the least risk, thus maximizing the societal benefits of a limited resource. LT evaluation is a multidisciplinary undertaking involving several specialists, assessment tools, and diagnostic testing. Although the steps involved in LT evaluation are relatively similar across different liver diseases, patients with NASH-related cirrhosis have unique demographic and clinical features that affect transplant outcomes and influence their LT evaluation. LT candidates with NASH should be assessed for metabolic syndrome and obesity, malnutrition and sarcopenia, frailty, and cardiovascular disease. Interventions that treat cardiometabolic co-morbidities and improve patients' nutrition and functionality should be considered in order to improve patient outcomes in the waitlist and after LT.

Nash Up, Virus Down: How the Waiting List Is Changing for Liver Transplantation: A Single Center Experience from Italy

Background and Objectives: Non-alcoholic steatohepatitis (NASH) has become the leading indication for liver transplantation in many countries, with a growing rate in the Western world. NASH patients are older and share a higher risk of comorbidities and cancer than patients with viral and/or alcoholic etiologies. The aims of this study were to evaluate waiting list (WL) registration and liver transplantation rates in patients with NASH-related cirrhosis at Padua University Hospital in the last fifteen years (1.2006–6.2020) and to compare clinical characteristics and indications for liver transplantation between patients with and without NASH, as well as the WL survival and post-transplant outcome. Materials and Methods: All adult patients with cirrhosis listed for liver transplantation at Padua University Hospital between 1.2006 and 6.2020 were retrospectively collected using a prospectively updated database; patients with NASH-related cirrhosis were divided by indication for liver transplantation (Dec-NASH vs. hepatocellular carcinoma (HCC)-NASH) and compared with patients with other etiologies of liver disease. The outcomes in terms of waiting list survival and post-transplant outcome were assessed. Results: One thousand four hundred and ninety-one adult cirrhotic patients were waitlisted during the study period. NASH patients accounted for 12% of all WL registrations, showing an increasing trend over time (from 2.5% in 2006 to 23% in 2020). In the last five years, NASH was the third, but most rapidly growing, indication for liver transplantation at our center. This trend was confirmed both for patients with decompensated cirrhosis (from 1.8% to 18%) and HCC as leading indication for transplantation (from 4% to 30%). NASH patients were older than non-NASH ones (mean ± SD age 59 ± 9 vs. 56 ± 9 years; p < 0.01), whereas no difference was found in gender or Child-Pugh of the model for end-stage liver disease score at WL registration. A majority (60.9%) of NASH patients underwent liver transplantation, showing 1-, 5- and 10-y post-transplant survivals of 86%, 73% and 60%, respectively. Conclusion: NASH cirrhosis has become a rapidly growing indication for liver transplantation at our center, both for HCC and decompensated disease, with good post-transplant survival.

Meta-analysis and systematic review: Prevalence, graft failure, mortality, and post-operative thrombosis in liver transplant recipients with pre-operative portal vein thrombosis

AIMS

This study seeks to evaluate the association between pre-transplant portal vein thrombosis (PVT) and overall survival, graft failure, waitlist mortality, and post-operative PVT after liver transplantation.

METHODS

A conventional pairwise meta-analysis between patients with and without pre-transplant PVT was conducted using hazard ratios or odds ratios where appropriate.

RESULTS

Prevalence of preoperative PVT was 11.6% (CI 9.70-13.7%). Pre-operative PVT was associated with increased overall mortality (HR 1.45, 95% CI 1.27-1.65) and graft loss (HR 1.58, 95% CI 1.34-1.85). In particular, grade 3 (HR 1.59, 95% CI 1.00-2.51) and 4 (HR 2.24, 95% CI 1.45-3.45) PVT significantly increased mortality, but not grade 1 or 2 PVT. Patients with PVT receiving living donor (HR 1.54, 95% CI 1.24-1.91) and deceased donor (HR 1.52, 95% CI 1.21-1.92) liver transplantation had increased mortality, with no significant difference between transplant types (P = .13). Furthermore, pre-transplant PVT was associated with higher occurrence of post-transplant PVT (OR 5.06, 95% CI 3.89-6.57). Waitlist mortality was not significantly increased in patients with pre-transplant PVT.

CONCLUSION

Graft failure, mortality, and post-operative PVT are more common in pre-transplant PVT patients, especially in grade 3 or 4 PVT. Prophylactic anticoagulation can be considered to reduce re-thrombosis and improve survival.

Non-alcoholic fatty liver disease and hematologic manifestations (Review)

Non-alcoholic fatty liver disease (NAFLD) is a multisystem disease, and it is associated with numerous extra-hepatic manifestations or additional co-occurring diseases. The aim of the present review was the identification and management of the hematologic manifestations of NAFLD. One of the triggers is considered to be iron abnormalities. Increased ferritin levels, hepatic iron deposits and iron overload are associated with NAFLD. The iron overload degree and severity are associated with the level of liver fibrosis and with the risk for hepatocellular carcinoma. Excess iron deposits refers to the dysmetabolic iron overload syndrome (DIOS) and it is characterized by steatosis associated with moderate tissue iron deposition and increased levels of serum ferritin, while the serum transferrin saturation was normal. Further prospective studies are necessary to determine whether NAFLD has an independent risk for hematologic symptoms, besides the known risk factors. Future studies are also needed in order to assess the increasing impact of NAFLD on the micro- and macro-vascular complications of this systemic disease.

Plasminogen activator inhibitor is significantly elevated in liver transplant recipients with decompensated NASH cirrhosis

Background

Non-alcoholic fatty liver disease is a prohaemostatic state with abnormal primary, secondary and tertiary haemostasis. Plasminogen activator inhibitor (PAI)-1 is the best-established marker for prohaemostasis in non-alcoholic fatty liver disease. While epidemiological studies demonstrate decompensated non-alcoholic steatohepatitis (NASH) cirrhosis patients have increased rates of venous thromboembolism, including portal vein thrombosis, mechanistic studies have focused exclusively on patients without or with compensated cirrhosis. We aimed to characterizecharacterise PAI-1 levels in decompensated NASH cirrhosis.

Methods

PAI-1 level was measured in consecutive adult liver transplant recipients immediately prior to liver transplantation. Multivariable models were constructed using linear regression to assess factors related to PAI-1 level.

Results

Forty-six subjects with mean age 57 (IQR 53–62) years and Model for Endstage Liver Disease (MELD) score of 34 (IQR 30–40) were enrolled. Baseline characteristics were similar between NASH (n=10) and non-NASH (n=36) subjects except for rates of diabetes and hyperlipidaemia. Mean PAI-1 level was greater in NASH (53.9, 95% CI 33.3 to 74.5 mg/mL) when compared with non-NASH (36.1, 95% CI 28.7 to 43.5), p=0.040. NASH remained independently predictive of PAI-1 level prior to transplant on adjusted multivariable modelling (β 40.13, 95% CI 14.41 to 65.86, p=0.003). Conclusions: PAI-1 level is significantly elevated in decompensated NASH cirrhosis independent of other pro-haemostatic factors. This may explain the greater rates of venous thromboembolism in decompensated NASH cirrhosis. Future study focusing on prevention of venous thromboembolism in this population is paramount to improve patient-oriented outcomes given the high morbidity and mortality of venous thromboembolism and the significant impact it has on transplant candidacy.

Portal vein thrombosis and renal dysfunction: a national comparative study of liver transplant recipients for NAFLD versus alcoholic cirrhosis

The prevalence of portal vein thrombosis (PVT), renal dysfunction (RD), and simultaneous PVT/RD in liver transplantation (LT) is poorly understood. We analyzed the prevalence of PVT, RD, simultaneous PVT/RD, and the outcomes of adult recipients of LT for nonalcoholic fatty liver disease (NAFLD) and alcoholic liver disease (ALD) between 2006 and 2016 in the United States. We found that the prevalence of PVT (7.2% → 11.3%), RD (33.8% → 39.2%), and simultaneous PVT/RD (2.4% → 4.5%) has increased significantly over the study period (all P‐values <0.05). NAFLD patients had a higher proportion of PVT (14.8% vs. 9.2%), RD (45.0% vs. 42.1%), and simultaneous PVT/RD (6.5% vs. 3.9%; all P‐values <0.05). 90‐day mortality was 3.8%, 6.3%, 6.8%, and 9.8% for PVT(−)/RD(−), PVT(−)/RD(+), PVT(+)/RD(−), and PVT(+)/RD(+) recipients, respectively (P < 0.01). 5‐year survival was 82.1%, 75.5%, 74.8%, and 71.1% for PVT(−)/RD(−), PVT(−)/RD(+), PVT(+)/RD(−), and PVT(+)/RD(+) recipients, respectively (P < 0.05). In conclusion, the prevalence of PVT, RD, and simultaneous PVT/RD has increased among LT recipients, especially for those with NAFLD. The short‐ and long‐term outcomes of recipients with PVT, RD, and simultaneous PVT/RD were inferior to patients without those risk factors irrespective of their indication for LT. No differences in patient outcomes were found between ALD and NAFLD recipients after stratification by risk factors.

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.

Peri-transplant management of nonalcoholic fatty liver disease in liver transplant candidates

The incidence of non-alcoholic fatty liver disease (NAFLD) is rapidly growing, affecting 25% of the world population. Non-alcoholic steatohepatitis (NASH) is the most severe form of NAFLD and affects 1.5% to 6.5% of the world population. Its rising incidence will make end-stage liver disease (ESLD) due to NASH the number one indication for liver transplantation (LT) in the next 10 to 20 years, overtaking Hepatitis C. Patients with NASH also have a high prevalence of associated comorbidities such as type 2 diabetes, obesity, metabolic syndrome, cardiovascular disease, and chronic kidney disease (CKD), which must be adequately managed during the peritransplant period for optimal post-transplant outcomes. The focus of this review article is to provide a comprehensive overview of the unique challenges these patients present in the peritransplant period, which comprises the pre-transplant, intraoperative, and immediate postoperative periods.

Extra-Hepatic Manifestations of Nonalcoholic Fatty Liver Disease: A Review

Nonalcoholic fatty liver disease (NAFLD) is now the leading cause of chronic liver disease worldwide with a strong association with metabolic syndrome. NAFLD is truly a systemic disease and is associated with a plethora of extra-hepatic manifestations or comorbidities. These are either related to secondary effects of associated obesity or from pathophysiological effects of insulin resistance in NAFLD. Three most common causes of increased morbidity and mortality associated with NAFLD are cardiovascular disease, liver disease, and cancer. In this narrative review, we will discuss comprehensively on cardiovascular disease, type 2 diabetes mellitus, and chronic kidney disease and will also highlight on malignancy especially colorectal cancer, pulmonary disorders including obstructive sleep apnea, endocrine disorders such as hypothyroidism and polycystic ovarian syndrome, dermatological disorders especially psoriasis, and hematological associations including iron overload and susceptibility to thrombosis. In addition to focusing on pathogenesis of these extrahepatic manifestations, we will highlight their clinical implications for physicians in routine clinical practice. Further, there remains an unmet need for safe and effective therapies and examining their benefits on these extra-hepatic manifestations among patients with NAFLD.

Development of a Model to Predict Portal Vein Thrombosis in Liver Transplant Candidates: The Portal Vein Thrombosis Risk Index

Portal vein thrombosis (PVT) is associated with inferior pretransplantation and posttransplantation outcomes. We aimed to create a predictive model to risk stratify transplant candidates for PVT. Data on adult transplants in the United States during the Model for End-Stage Liver Disease (MELD) era through September 2016 were reviewed. We constructed and validated a scoring system composed of routine, readily available clinical information to predict the development of incident PVT at 12 months from transplantation listing. A total of 66,568 liver transplant candidates were dichotomized into 2 groups to construct (n = 34,751) and validate (n = 31,817) a scoring system. In general, the derivation and validation cohorts were clinically similar. Although nonalcoholic steatohepatitis was a significant predictor of incident PVT (hazard ratio, 1.29; 95% confidence interval, 1.08-1.54; P < 0.001), age, MELD score, and moderate-to-severe ascites were also associated with increased risk. African American race was associated with decreased risk. A scoring system (PVT risk index [RI]) of these 5 variables had an area under the curve of 0.71 and 0.70 in both derivation and validation cohorts, respectively. By applying the low cutoff score of 2.6, incident PVT could be accurately excluded (negative predictive value 94%). Using the high cutoff score of 4.6 (positive predictive value 85%), PVT could be diagnosed with high accuracy. The PVT-RI predicts which candidates awaiting lifesaving liver transplantation will and will not develop future PVT. Although this scoring system will require prospective validation, it provides a powerful new tool for the clinician when risk stratifying cirrhosis patients prior to liver transplantation for future PVT development.