Acute-on-chronic liver failure: extracorporeal liver assist devices. Curr Opin Crit Care. 2011;17:195-203. [PMID: 21346566 DOI: 10.1097/mcc.0b013e328344b3aa]

Acute-on-chronic liver failure: far to go-a review

Acute-on-chronic liver failure (ACLF) has been recognized as a severe clinical syndrome based on the acute deterioration of chronic liver disease and is characterized by organ failure and high short-term mortality. Heterogeneous definitions and diagnostic criteria for the clinical condition have been proposed in different geographic regions due to the differences in aetiologies and precipitating events. Several predictive and prognostic scores have been developed and validated to guide clinical management. The specific pathophysiology of ACLF remains uncertain and is mainly associated with an intense systemic inflammatory response and immune-metabolism disorder based on current evidence. For ACLF patients, standardization of the treatment paradigm is required for different disease stages that may provide targeted treatment strategies for individual needs.

Acute-on-chronic liver failure is independently associated with higher mortality for cirrhotic patients with acute esophageal variceal hemorrhage: Retrospective cohort study

BACKGROUND

Acute esophageal variceal hemorrhage (AEVH) is a common complication of cirrhosis and might precipitate multi-organ failure, causing acute-on-chronic liver failure (ACLF).

AIM

To analyze if the presence and grading of ACLF as defined by European Society for the Study of the Liver-Chronic Liver Failure (EASL-CLIF) is able to predict mortality in cirrhotic patients presenting AEVH.

METHODS

Retrospective cohort study executed in Hospital Geral de Caxias do Sul. Data from medical records from 2010 to 2016 were obtained by searching the hospital electronic database for patients who received terlipressin. Medical records were reviewed in order to determine the diagnosis of cirrhosis and AEVH, including 97 patients. Kaplan-Meier survival analysis was used for univariate analysis and a stepwise approach to the Cox regression for multivariate analysis.

RESULTS

All- cause mortality for AEVH patients was 36%, 40.2% and 49.4% for 30-, 90- and 365-day, respectively. The prevalence of ACLF was 41.3%. Of these, 35% grade 1, 50% grade 2 and 15% grade 3. In multivariate analysis, the non-use of non-selective beta-blockers, presence and higher grading of ACLF and higher Model for End-Stage Liver Disease scores were independently associated with higher mortality for 30-day with the addition of higher Child-Pugh scores for 90-day period.

CONCLUSION

Presence and grading of ACLF according to the EASL-CLIF criteria was independently associated with higher 30- and 90-day mortality in cirrhotic patients admitted due to AEVH.

Treatment of Hepatitis E

Hepatitis E virus (HEV) infections are the most common cause of acute hepatitis, but they can also take a chronic course. There is no specific therapy for acute hepatitis, and current treatment is supportive. Choosing ribavirin as the first-line therapy for chronic HEV is advisable, especially immunosuppressed individuals. Moreover, ribavirin therapy in the acute phase of infection provides major benefits for those at high risk of acute liver failure (ALF)/acute-on-chronic liver failure (ACLF). Pegylated interferon α has been used successfully for treatment of hepatitis E but is associated with major side effects. Cholestasis is one of the most common, but devastating, manifestations in hepatitis E. Current therapy for HEV aims to treat symptoms. Therapy generally involves several measures, such as vitamins, albumin, and plasma for supporting treatment, symptomatic treatment for cutaneous pruritus, ursodeoxycholic acid, Obeticholic acid, S-adenosylmethionine, etc. for removing jaundice. HEV infection during pregnancy and patients with underlying liver disease may develop liver failure. For these patients, active monitoring, standard care, and supportive treatment are the foundations. Ribavirin has successfully been used to prevent liver transplantation (LT). Prevention and treatment of complications are important for treatment of liver failure. Liver support devices are intended to support liver function until such time as native liver function recovers, or until LT. LT is widely considered as irreplaceable and definitive treatment for liver failure, particularly for patients who do not improve with supportive measures to sustain life.

Adverse events, short- and long-term outcomes of extra corporeal liver therapy in the intensive care unit: 16 years experience with MARS® in a single center

Background

Molecular Adsorbent Recirculating System (MARS®) is a non-biological artificial liver device. The benefit risk ratio between uncertain clinical effects and potential adverse events remains difficult to assess. We sought to describe adverse events related to MARS® therapy as well as biological and clinical effects.

Methods

All intensive care unit (ICU) admissions to whom MARS® therapy was prescribed from March 2005 to August 2021 were consecutively and prospectively included. The main endpoint was the incidence of adverse events related to MARS® therapy. Secondary endpoints were the biological and clinical effects of MARS® therapy.

Results

We reported 180 admissions treated with MARS® therapy. Among the 180 admissions, 56 (31.1%) were for acute-on-chronic liver failure, 32 (17.8%) for acute liver failure, 28 (15.5%) for post-surgery liver failure, 52 (28.9%) for pruritus and 12 (6.7%) for drug intoxication. At least one adverse event occurred in 95 (52.8%) admissions. Thrombocytopenia was the most frequent adverse event which was recorded in 55 admissions (30.6%). Overall, platelets count was 131 (± 95) × 10⁹/L before and 106 (± 72) × 10⁹/L after MARS® therapy (p < .001). After MARS® therapy, total bilirubin was significantly decreased in all groups (p < 0.05). Hepatic encephalopathy significantly improved in both the acute-on-chronic and in the acute liver failure group (p = 0.01). In the pruritus group, pruritus intensity score was significantly decreased after MARS® therapy (p < 0.01).

Conclusion

In this large cohort of patients treated with MARS® therapy we report frequent adverse events. Thrombocytopenia was the most frequent adverse event. In all applications significant clinical and biological improvements were shown with MARS® therapy.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13054-022-04165-z.

Acute-on-Chronic Liver Failure Clinical Guidelines

In patients with cirrhosis and chronic liver disease, acute-on-chronic liver failure is emerging as a major cause of mortality. These guidelines indicate the preferred approach to the management of patients with acute-on-chronic liver failure and represent the official practice recommendations of the American College of Gastroenterology. The scientific evidence for these guidelines was evaluated using the Grading of Recommendations, Assessment, Development, and Evaluation process. In instances where the evidence was not appropriate for Grading of Recommendations, Assessment, Development, and Evaluation, but there was consensus of significant clinical merit, key concept statements were developed using expert consensus. These guidelines are meant to be broadly applicable and should be viewed as the preferred, but not only, approach to clinical scenarios.

ACUTE-ON-CHRONIC LIVER FAILURE IS INDEPENDENTLY ASSOCIATED WITH LOWER SURVIVAL IN PATIENTS WITH SPONTANEOUS BACTERIAL PERITONITIS

BACKGROUND

Spontaneous bacterial peritonitis (SBP) is a decompensation of cirrhosis with an in-hospital mortality ranging from 20% to 40%.

OBJECTIVE

The purpose of this study is to analyze if EASL-CLIF definition of acute-on-chronic liver failure (ACLF) is able to predict mortality in cirrhotic patients with SBP.

METHODS

Historical cohort study conducted in a public tertiary care teaching hospital. Data from medical records from January 2009 to July 2016 were obtained by searching the hospital electronic database for samples of ascites collected in the period. Electronic and physical medical records were analyzed and patients were included if they were over 18-years old, with cirrhosis and an ascites fluid compatible with SBP: 69 patients were included. Liver-specific scores were calculated and Kaplan-Meier survival analysis was used for univariate analysis and a stepwise approach to the Cox regression for multivariate analysis.

RESULTS

All cause mortality was 44%, 56.5% and 74% for 28-, 90- and 365-day, respectively. The prevalence of ACLF was 58%. Of these, 65% grade 1, 17.5% grade 2 and 17.5% grade 3. In multivariate analysis, the use of proton-pump inhi-bitors, alanine transaminase lower than 40 U/L, hemoglobin higher than 9 g/dL, absence of ACLF and lower CLIF-SOFA and MELD scores were independently associated with higher survival for both 28- and 90-day interval.

CONCLUSION

The presence of ACLF and higher CLIF-SOFA scores were independently associated with higher 28- and 90-day mortality in cirrhotic patients admitted due to SBP.

Liver Organoids: Formation Strategies and Biomedical Applications

The liver is the most important digestive organ in the body. Several studies have explored liver biology and diseases related to the liver. However, most of these studies have only explored liver development, mechanism of liver regeneration and pathophysiology of liver diseases mainly based on two-dimensional (2D) cell lines and animal models. Traditional 2D cell lines do not represent the complex three-dimensional tissue architecture whereas animal models are limited by inter-species differences. These shortcomings limit understanding of liver biology and diseases. Liver organoid technology is effective in elucidating structural and physiological characteristics and basic tissue-level functions of liver tissue. In this review, formation strategies and a wide range of applications in biomedicine of liver organoid are summarized. Liver organoids are derived from single type cell culture, such as induced pluripotent stem cells (iPSCs), adult stem cells, primary hepatocytes, and primary cholangiocytes and multi-type cells co-culture, such as iPSC-derived hepatic endoderm cells co-cultured with mesenchymal stem cells and umbilical cord-derived endothelial cells. In vitro studies report that liver organoids are a promising model for regenerative medicine, organogenesis, liver regeneration, disease modelling, drug screening and personalized treatment. Liver organoids are a promising in vitro model for basic research and for development of clinical therapeutic interventions for hepatopathy.

Evidence-based protocol for diagnosis and treatment of hepatorenal syndrome is independently associated with lower mortality

BACKGROUND

Hepatorenal syndrome (HRS) is the deadliest complication of cirrhosis. The purpose of this study is to analyze if the use of a protocol for HRS is associated with higher survival in these patients.

METHODS

An evidence-based protocol for the diagnosis and treatment of HRS was instituted in 2013. Data from medical records from 2010 to 2016 were obtained by searching the hospital database for patients who received terlipressin, in the three years before and after the institution of the protocol. Data were reviewed to confirm the diagnosis of HRS and multiple variables were collected. Liver-specific scores were calculated and a stepwise Cox regression approach was used for univariate and multivariate analysis.

RESULTS

The study included 46 patients, 20 from the pre-protocol period and 26 from the post-protocol period. Respectively, mortality at 30 days, 90 days and 365 days was 75%, 75% and 90% for the pre-protocol period, and 61%, 69% and 80% for the post-protocol period. In the multivariate analysis, an aspartate aminotransferase (AST) of <40U/L, the pre-protocol period and higher Child-Turcotte-Pugh scores were associated with higher 30-day and 90-day mortality. The total mean dose of terlipressin and human albumin used per patient was reduced from 27mg to 22mg and from 236g to 144g, respectively, after the institution of the protocol. This was not associated with higher mortality.

CONCLUSION

The use of an evidence-based protocol for the treatment of HRS translated into a higher survival. The authors suggest that the use of evidence-based protocols for the diagnosis and treatment of HRS could reduce cost and mortality in tertiary hospitals.

A prognostic score for patients with acute-on-chronic liver failure treated with plasma exchange-centered artificial liver support system

Artificial liver support system (ALSS) therapy is widely used in patients with hepatitis B virus-related acute-on-chronic liver failure (HBV-ACLF). We aimed to develop a predictive score to identify the subgroups who may benefit from plasma exchange (PE)-centered ALSS therapy. A total of 601 patients were retrospectively enrolled and randomly divided into a derivation cohort of 303 patients and a validation cohort of 298 patients for logistic regression analysis, respectively. Five baseline variables, including liver cirrhosis, total bilirubin, international normalized ratio of prothrombin time, infection and hepatic encephalopathy, were found independently associated with 3-month mortality. A predictive PALS model and the simplified PALS score were developed. The predicative value of PALS score (AUROC = 0.818) to 3-month prognosis was as capable as PALS model (AUROC = 0.839), R score (AUROC = 0.824) and Yue-Meng’ score (AUROC = 0.810) (all p > 0.05), and superior to CART model (AUROC = 0.760) and MELD score (AUROC = 0.765) (all p < 0.05). The PALS score had significant linear correlation with 3-month mortality (R² = 0.970, p = 0.000). PALS score of 0–2 had both sensitivity and negative predictive value of > 90% for 3-month mortality, while PALS score of 6–9 had both specificity and positive predictive value of > 90%. Patients with PALS score of 3–5 who received 3–5 sessions of ALSS therapy had much lower 3-month mortality than those who received 1–2 sessions (32.8% vs. 59.2%, p < 0.05). The more severe patients with PALS score of 6–9 could still benefit from ≥ 6 sessions of ALSS therapy compared to ≤ 2 sessions (63.6% vs. 97.0%, p < 0.05). The PALS score could predict prognosis reliably and conveniently. It could identify the subgroups who could benefit from PE-centered ALSS therapy, and suggest the reasonable sessions.

Trial registration: Chinese Clinical Trial Registry, ChiCTR2000032055. Registered 19th April 2020, http://www.chictr.org.cn/showproj.aspx?proj=52471.

Artificial liver support system therapy in acute-on-chronic hepatitis B liver failure: Classification and regression tree analysis

Artificial liver support systems (ALSS) are widely used to treat patients with hepatitis B virus-related acute-on-chronic liver failure (HBV-ACLF). The aims of the present study were to investigate the subgroups of patients with HBV-ACLF who may benefit from ALSS therapy, and the relevant patient-specific factors. 489 ALSS-treated HBV-ACLF patients were enrolled, and served as derivation and validation cohorts for classification and regression tree (CART) analysis. CART analysis identified three factors prognostic of survival: hepatic encephalopathy (HE), prothrombin time (PT), and total bilirubin (TBil) level; and two distinct risk groups: low (28-day mortality 10.2–39.5%) and high risk (63.8–91.1%). The CART model showed that patients lacking HE and with a PT ≤ 27.8 s and a TBil level ≤455 μmol/L experienced less 28-day mortality after ALSS therapy. For HBV-ACLF patients with HE and a PT > 27.8 s, mortality remained high after such therapy. Patients lacking HE with a PT ≤ 27.8 s and TBil level ≤ 455 μmol/L may benefit markedly from ALSS therapy. For HBV-ACLF patients at high risk, unnecessary ALSS therapy should be avoided. The CART model is a novel user-friendly tool for screening HBV-ACLF patient eligibility for ALSS therapy, and will aid clinicians via ACLF risk stratification and therapeutic guidance.

Graphene-based 3D scaffolds in tissue engineering: fabrication, applications, and future scope in liver tissue engineering

Tissue engineering embraces the potential of recreating and replacing defective body parts by advancements in the medical field. Being a biocompatible nanomaterial with outstanding physical, chemical, optical, and biological properties, graphene-based materials were successfully employed in creating the perfect scaffold for a range of organs, starting from the skin through to the brain. Investigations on 2D and 3D tissue culture scaffolds incorporated with graphene or its derivatives have revealed the capability of this carbon material in mimicking in vivo environment. The porous morphology, great surface area, selective permeability of gases, excellent mechanical strength, good thermal and electrical conductivity, good optical properties, and biodegradability enable graphene materials to be the best component for scaffold engineering. Along with the apt microenvironment, this material was found to be efficient in differentiating stem cells into specific cell types. Furthermore, the scope of graphene nanomaterials in liver tissue engineering as a promising biomaterial is also discussed. This review critically looks into the unlimited potential of graphene-based nanomaterials in future tissue engineering and regenerative therapy.

Hepatic encephalopathy: current challenges and future prospects

Hepatic encephalopathy (HE) is a common complication of liver dysfunction, including acute liver failure and liver cirrhosis. HE presents as a spectrum of neuropsychiatric symptoms ranging from subtle fluctuating cognitive impairment to coma. It is a significant contributor of morbidity in patients with liver disease. HE is observed in acute liver failure, liver bypass procedures, for example, shunt surgry and transjugular intrahepatic portosystemic shunt, and cirrhosis. These are classified as Type A, B and C HE, respectively. HE can also be classified according to whether its presence is overt or covert. The pathogenesis is linked with ammonia and glutamine production, and treatment is based on mechanisms to reduce the formation and/or removal of these compounds. There is no specific diagnostic test for HE, and diagnosis is based on clinical suspicion, excluding other causes and use of clinical tests that may support its diagnosis. Many tests are used in trials and experimentally, but have not yet gained universal acceptance. This review focuses on the definitions, pathogenesis and treatment of HE. Consideration will be given to existing treatment, including avoidance of precipitating factors and novel therapies such as prebiotics, probiotics, antibiotics, laxatives, branched-chain amino acids, shunt embolization and the importance of considering liver transplant in appropriate cases.

Molecular Adsorbent Recirculating System Can Reduce Short-Term Mortality Among Patients With Acute-on-Chronic Liver Failure-A Retrospective Analysis

Supplemental Digital Content is available in the text.

Objectives:

Acute-on-chronic liver failure is associated with numerous consecutive organ failures and a high short-term mortality rate. Molecular adsorbent recirculating system therapy has demonstrated beneficial effects on the distinct symptoms, but the associated mortality data remain controversial.

Design:

Retrospective analysis of acute-on-chronic liver failure patients receiving either standard medical treatment or standard medical treatment and molecular adsorbent recirculating system. Secondary analysis of data from the prospective randomized Recompensation of Exacerbated Liver Insufficiency with Hyperbilirubinemia and/or Encephalopathy and/or Renal Failure trial by applying the recently introduced Chronic Liver Failure-criteria.

Setting:

Medical Departments of University Hospital Muenster (Germany).

Patients:

This analysis was conducted in two parts. First, 101 patients with acute-on-chronic liver failure grades 1–3 and Chronic Liver Failure-C-Organ Failure liver subscore equals to 3 but stable pulmonary function were identified and received either standard medical treatment (standard medical treatment, n = 54) or standard medical treatment and molecular adsorbent recirculating system (n = 47) at the University Hospital Muenster. Second, the results of this retrospective analysis were tested against the Recompensation of Exacerbated Liver Insufficiency with Hyperbilirubinemia and/or Encephalopathy and/or Renal Failure trial.

Interventions:

Standard medical treatment and molecular adsorbent recirculating system.

Measurements and Main Results:

Additionally to improved laboratory variables (bilirubin and creatinine), the short-term mortality (up to day 14) of the molecular adsorbent recirculating system group was significantly reduced compared with standard medical treatment. A reduced 14-day mortality rate was observed in the molecular adsorbent recirculating system group (9.5% vs 50.0% with standard medical treatment; p = 0.004), especially in patients with multiple organ failure (acute-on-chronic liver failure grade 2–3). Concerning the affected organ system, this effect of molecular adsorbent recirculating system on mortality was particularly evident among patients with increased kidney, brain, or coagulation Chronic Liver Failure-C-Organ Failure subscores. Subsequent reanalysis of the Recompensation of Exacerbated Liver Insufficiency with Hyperbilirubinemia and/or Encephalopathy and/or Renal Failure dataset with adoption of the Chronic Liver Failure-classification resulted in similar findings.

Conclusions:

Molecular adsorbent recirculating system treatment was associated with an improved short-term survival of patients with acute-on-chronic liver failure and multiple organ failure. Among these high-risk patients, molecular adsorbent recirculating system treatment might bridge to liver recovery or liver transplantation.

A comparison among three different apheretic techniques for treatment of hyperbilirubinemia

Liver failure is associated to high mortality due to the accumulation of protein-bound metabolites, such as bilirubin, not removed by conventional hemodialysis. Different methods can efficiently remove them, such as the molecular adsorbent recirculating system (MARS), plasma exchange (PEX), and bilirubin or plasma adsorption perfusion (PAP). No direct comparison exists between MARS, PEX and PAP, and current guidelines do not specify which method (and when) to use. We have retrospectively evaluated MARS, PEX and PAP in their effectiveness in lowering plasma bilirubin concentration, and their effects on liver and kidney function. A total of 98 patients have been recruited, which comprised 68 patients treated with PAP (177 sessions), 16 patients with PEX (41 sessions) and 11 patients with MARS (21 sessions). Bilirubin, creatinine, liver enzymes were analyzed before and after the first treatment with each technique. The three methods did not differ for bilirubin lowering efficiency, with MARS showing only slightly less effective reductions. Finally, the three techniques did not differ in the amount of change of cholinesterase, but a lower reduction in AST was found using PAP. Our retrospective observation is one of the largest case series of hepatic failure treated with bilirubin absorption. The choice of the technique cannot be based on the desired reduction in bilirubin concentration. Based on costs and duration of treatment, we suggest that PAP could be considered as a first-line approach. In case of kidney involvement, MARS remains a valuable option.

A Randomized Controlled Trial of Glycyrrhizin Plus Tenofovir vs. Tenofovir in Chronic Hepatitis B with Severe Acute Exacerbation

Objectives:

Severe acute exacerbation (SAE) of chronic hepatitis B (CHB) may progress to liver failure with high potential mortality despite the prompt treatment with nucleos(t)ide analogs. This study aimed to evaluate the efficacy and safety of glycyrrhizin in the treatment of CHB with SAE.

Methods:

Sixty patients with SAE of CHB were randomly treated with tenofovir plus intravenous glycyrrhizin (group A, n=30) or with tenofovir alone (group B, n=30). Primary end points were the improvement of serum levels of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) and model for end-stage liver disease (MELD) score. Secondary end point was overall mortality or receipt of liver transplantation by week 24.

Results:

Patients in group A had significant reductions of serum AST and ALT levels from baseline at days 3, 5, 8, and 15 than those in group B (all P<0.05). The MELD score significantly decreased since week 1 in the group A patients, whereas there were no changes relative to baseline in group B patients at weeks 1 and 2. By week 24, one (3.3%) of group A patients and four (13.3%) of group B patients died (n=3) or received liver transplantation (n=1) (P=0.177). Multivariate analysis identified baseline MELD score (P=0.021) as an independent factor for mortality or receipt of liver transplantation. There were no differences in the rates of grade 3 hypertension, hypokalemia and ascites between two groups.

Conclusions:

Early introduction of glycyrrhizin can be safe and helpful for patients with SAE of CHB.

Current state of knowledge of hepatic encephalopathy (part IV): Management of Hepatic Encephalopathy by liver support systems

Hepatic Encephalopathy is a devastating complication of End-Stage Liver Disease. In its severe grades it requires extra intervention beyond the standard medical approaches. In this article were view the role of liver support systems in managing hepatic encephalopthy.

First clinical experience in 14 patients treated with ADVOS: a study on feasibility, safety and efficacy of a new type of albumin dialysis

BACKGROUND

Liver failure (LF) is associated with prolonged hospital stay, increased cost and substantial mortality. Due to the limited number of donor organs, extracorporeal liver support is suggested as an appealing concept to "bridge to transplant" or to avoid transplant in case of recovery. ADVanced Organ Support (ADVOS) is a new type of albumin dialysis, that provides rapid regeneration of toxin-binding albumin by two purification circuits altering the binding capacities of albumin by biochemical (changing of pH) and physical (changing of temperature) modulation of the dialysate. It was the aim of this study to evaluate feasibility, efficacy and safety of ADVOS in the first 14 patients ever treated with this procedure.

METHODS

Patients included suffered from acute on chronic LF (n = 9) or "secondary" LF (n = 5) which resulted from non-hepatic diseases such as sepsis. The primary endpoint was the change of serum bilirubin, creatinine and serum BUN levels before and after the first treatment with ADVOS. The Wilcoxon Signed Rank test for paired samples was used to analyze the data.

RESULTS

A total of 239 treatments (1 up to 101 per patient) were performed in 14 patients (6 female, 8 male). Mean age 54 ± 13; MELD-score 34 ± 7; CLIF-SOFA 15 ± 3. Serum bilirubin levels were significantly decreased by 32% during the first session (26.0 ± 15.4 vs. 17.7 ± 10.5 mg/dl; p = 0.001). Similarly, serum creatinine (2.2 ± 0.8 vs. 1.6 ± 0.7 mg/dl; p = 0.005) and serum BUN (49.4 ± 23.3 vs. 31.1 ± 19.7 mg/dl; p = 0.003), were significantly lowered by 27% and 37%, respectively. None of the treatment sessions had to be interrupted due to side effects related to the procedure.

CONCLUSION

ADVOS efficiently eliminates water- and protein-bound toxins in humans with LF. ADVOS is feasible in patients with advanced LF which is emphasized by a total number of more than 100 treatment sessions in one single patient.

Chronic Hepatitis B with Spontaneous Severe Acute Exacerbation

Chronic hepatitis B virus (HBV) infection is a major global health problem with an estimated 400 million HBV carriers worldwide. In the natural history of chronic hepatitis B (CHB), spontaneous acute exacerbation (AE) is not uncommon, with a cumulative incidence of 10%–30% every year. While exacerbations can be mild, some patients may develop hepatic decompensation and even die. The underlying pathogenesis is possibly related to the activation of cytotoxic T lymphocyte-mediated immune response against HBV. An upsurge of serum HBV DNA usually precedes the rise of alanine aminotransferase (ALT) and bilirubin. Whether antiviral treatment can benefit CHB with severe AE remains controversial, but early nucleos(t)ide analogues treatment seemed to be associated with an improved outcome. There has been no randomized study that compared the effects of different nucleos(t)ide analogues (NA) in the setting of CHB with severe AE. However, potent NAs with good resistance profiles are recommended. In this review, we summarized current knowledge regarding the natural history, pathogenetic mechanisms, and therapeutic options of CHB with severe AE.

Acute-on-chronic liver failure: Pathogenesis, prognostic factors and management

Acute-on-chronic liver failure (ACLF) is increasingly recognized as a complex syndrome that is reversible in many cases. It is characterized by an acute deterioration of liver function in the background of a pre-existing chronic liver disease often associated with a high short-term mortality rate. Organ failure (OF) is always associated, and plays a key role in determining the course, and the outcome of the disease. The definition of ACLF remains controversial due to its overall ambiguity, with several disparate criteria among various associations dedicated to the study of liver diseases. Although the precise pathogenesis needs to be clarified, it appears that an altered host response to injury might be a contributing factor caused by immune dysfunction, ultimately leading to a pro-inflammatory status, and eventually to OF. The PIRO concept (Predisposition, Insult, Response and Organ Failure) has been proposed to better approach the underlying mechanisms. It is accepted that ACLF is a different and specific form of liver failure, where a precipitating event is always involved, even though it cannot always be ascertained. According to several studies, infections and active alcoholism often trigger ACLF. Viral hepatitis, gastrointestinal haemorrhage, or drug induced liver injury, which can also provoke the syndrome. This review mainly focuses on the physiopathology and prognostic aspects. We believe these features are essential to further understanding and providing the rationale for improveddisease management strategies.

Acute-on-Chronic Liver Failure

Over the past 2 decades, the concept of acute-on-chronic liver failure (ACLF) has been proposed as an alternate path in the natural history of decompensated cirrhosis. ACLF thus is characterized by the presence of a precipitating event (identified or unidentified) in subjects with underlying chronic liver disease leading to rapid progression of liver injury and ending in multi-organ dysfunction characterized by high short-term mortality. Multiple organ failure and an increased risk for mortality are key to the diagnosis of ACLF. The prevalence of ACLF ranges from 24% to 40% in hospitalized patients. The pathophysiological basis of ACLF can be explained using the following 4-part model: predisposing event, injury caused by a precipitating event, response to injury, and organ failure. Although several mathematic scores have been proposed for identifying outcomes with ACLF, it is as yet unclear whether these organ failure scores are truly prognostic or only reflective of the dying process. Treatment paradigms continue to evolve but consist of early recognition, supportive intensive care, and consideration of liver transplantation before onset of irreversible multiple organ failure.

Albumin Dialysis for Liver Failure: A Systematic Review

Albumin dialysis is the best-studied extracorporeal nonbiologic liver support system as a bridge or destination therapy for patients with liver failure awaiting liver transplantation or recovery of liver function. We performed a systematic review to examine the efficacy and safety of 3 albumin dialysis systems (molecular adsorbent recirculating system [MARS], fractionated plasma separation, adsorption and hemodialysis [Prometheus system], and single-pass albumin dialysis) in randomized trials for supportive treatment of liver failure. PubMed, Ovid, EMBASE, Cochrane's Library, and ClinicalTrials.gov were searched. Two authors independently screened citations and extracted data on patient characteristics, quality of reports, efficacy, and safety end points. Ten trials (7 of MARS and 3 of Prometheus) were identified (620 patients). By meta-analysis, albumin dialysis achieved a net decrease in serum total bilirubin level relative to standard medical therapy of 8.0 mg/dL (95% confidence interval [CI], -10.6 to -5.4) but not in serum ammonia or bile acids. Albumin dialysis achieved an improvement in hepatic encephalopathy relative to standard medical therapy with a risk ratio of 1.55 (95% CI, 1.16-2.08) but had no effect survival with a risk ratio of 0.95 (95% CI, 0.84-1.07). Because of inconsistency in the reporting of adverse events, the safety analysis was limited but did not demonstrate major safety concerns. Use of albumin dialysis as supportive treatment for liver failure is successful at removing albumin-bound molecules, such as bilirubin and at improving hepatic encephalopathy. Additional experience is required to guide its optimal use and address safety concerns.

Treatment of Overt Hepatic Encephalopathy

Hepatic encephalopathy (HE) is defined by an altered mental status in the setting of portosystemic shunting, with or without cirrhosis. The basis of HE is probably multi-factorial, but increased ammonia delivery to the brain is thought to play a pivotal role. Medical therapies have typically focused on reducing blood ammonia concentrations. These measures are moderately effective, but further improvements will require identification of new therapeutic targets. Two medications, lactulose and rifaximin, are currently approved for the treatment of HE in the USA - new compounds are available off-label, and are in clinical trials. The presence of HE is associated with a higher risk of death in cirrhotic patients. Liver transplantation typically cures HE, but HE does not increase the MELD score, and therefore does not contribute to the likelihood of liver transplantation.

Advanced therapeutic strategies for HBV-related acute-on-chronic liver failure

BACKGROUND

Acute-on-chronic liver failure (ACLF) is increasingly recognized as a distinct clinical entity and is associated with a high short-term mortality. The most common cause of ACLF is chronic hepatitis B worldwide. Currently, there is no standardized approach for the management of ACLF and the efficacy and safety of therapeutic modalities are uncertain.

DATA SOURCES

PubMed and Web of Science were searched for English-language articles. The search criteria focused on clinical trials and observational studies on the treatment of patients with HBV-related ACLF.

RESULTS

Therapeutic approaches for ACLF in patients with chronic hepatitis B included nucleos(t)ide analogues, artificial liver support systems, immune regulatory therapy, stem cell therapy and liver transplantation. All of these therapeutic approaches have shown the potential to improve liver function and increase patients' survival rate, but most of the studies were not randomized or controlled.

CONCLUSION

Substantial challenges for the treatment of HBV-related ACLF remain and further basic research and randomized controlled clinical trials are needed.

Acute-on-chronic liver failure: A new syndrome that will re-classify cirrhosis

Acute-on-chronic liver failure (ACLF) is a recently recognized syndrome characterized by acute decompensation (AD) of cirrhosis and organ/system failure(s) (organ failure: liver, kidney, brain, coagulation, circulation and/or respiration) and extremely poor survival (28-day mortality rate 30-40%). ACLF occurs in relatively young patients. It is especially frequent in alcoholic- and untreated hepatitis B associated-cirrhosis, in addition it is related to bacterial infections and active alcoholism, although in 40% of cases no precipitating event can be identified. It may develop at any time during the course of the disease in the patient (from compensated to long-standing cirrhosis). The development of ACLF occurs in the setting of a systemic inflammation, the severity of which correlates with the number of organ failures and mortality. Systemic inflammation may cause ACLF through complex mechanisms including an exaggerated inflammatory response and systemic oxidative stress to pathogen- or danger/damage-associated molecular patterns (immunopathology) and/or alteration of tissue homeostasis to inflammation caused either by the pathogen itself or through a dysfunction of tissue tolerance. A scoring system composed of three scores (CLIF-C OFs, CLIF-C AD, and CLIF-C ACLFs) specifically designed for patients with AD, with and without ACLF, allows a step-wise algorithm for a rational indication of therapy. The management of ACLF should be carried out in enhanced or intensive care units. Current therapeutic measures comprise the treatment for associated complications, organ failures support and liver transplantation.

Artificial liver support system improves short- and long-term outcomes of patients with HBV-associated acute-on-chronic liver failure: a single-center experience

For patients with acute-on-chronic liver failure (ACLF), artificial liver support system (ALSS) may help prolong lifespan and function as a bridge to liver transplantation (LT), but data on its long-term benefit are lacking. We conducted this prospective, controlled study to determine the efficacy of ALSS and the predictors of mortality in patients with hepatitis B virus (HBV)-associated ACLF.From January 2003 to December 2007, a total of 234 patients with HBV-associated ACLF not eligible for LT were enrolled in our study. They were allocated to receive either plasma exchange centered ALSS plus standard medical therapy (SMT) (ALSS group, n=104) or SMT alone (control group, n=130). All the patients were followed-up for at least 5 years, or until death.At 90 days, the survival rate of ALSS group was higher than that of the control group (62/104 [60%] vs 61/130 [47%], respectively; P<0.05). Median survival was 879 days in the ALSS group (43% survival at 5 years) and 649 days in the control group (31% survival at 5 years, log-rank P<0.05). ALSS was found to be associated with favorable outcome of these patients by both univariate and multivariate analysis. Multivariate Cox regression analysis also revealed that lower serum sodium levels, higher grades of encephalopathy, presence of cirrhosis, hepatorenal syndrome, and higher model for end-stage liver disease scores were independent predictors for both 90-day and 5-year mortality due to ACLF.Our findings suggest that ALSS is safe and may improve the short- and long-term prognosis of patients with HBV-associated ACLF.

Acute-on-chronic liver failure

The Model for End-Stage Liver Disease (MELD) has been the single best predictor of outcome of the progression of cirrhosis. Acute-on-chronic liver failure (ACLF) has been proposed as an alternative path in the natural history of cirrhosis. ACLF occurs in patients with chronic liver disease and is characterized by a precipitating event, resulting in acute deterioration in liver function, multiorgan system failure, and high short-term mortality. In this review, the natural course of patients with ACLF, especially as it relates to management of cirrhotic patients on the transplant waiting list, and its impact on liver transplantation outcomes are defined.

Cell and tissue engineering for liver disease

Despite the tremendous hurdles presented by the complexity of the liver's structure and function, advances in liver physiology, stem cell biology and reprogramming, and the engineering of tissues and devices are accelerating the development of cell-based therapies for treating liver disease and liver failure. This State of the Art Review discusses both the near- and long-term prospects for such cell-based therapies and the unique challenges for clinical translation.

Cold Storage of Rat Hepatocyte Spheroids

Cell-based therapies for liver disease rely on a high-quality supply of hepatocytes and a means for storage during transportation from site of isolation to site of usage. Unfortunately, frozen cryopreservation is associated with unacceptable loss of hepatocyte viability after thawing. The purpose of this study was to optimize conditions for cold storage of rat hepatocyte spheroids without freezing. Rat hepatocytes were isolated by a two-step perfusion method; hepatocyte spheroids were formed during 48 h of rocked culture in serum-free medium (SFM). Spheroids were then maintained in rocked culture at 37°C (control condition) or cold stored at 4°C for 24 or 48 h in six different cold storage solutions: SFM alone; SFM + 1 mM deferoxamine (Def); SFM + 1 μM cyclosporin A (CsA); SFM + 1 mM Def + 1 μM CsA, University of Wisconsin (UW) solution alone, UW + 1 mM Def. Performance metrics after cold storage included viability, gene expression, albumin production, and functional activity of cytochrome P450 enzymes and urea cycle proteins. We observed that cold-induced injury was reduced significantly by the addition of the iron chelator (Def) to both SFM and UW solution. Performance metrics (ammonia detoxification, albumin production) of rat hepatocyte spheroids stored in SFM + Def for 24 h were significantly increased from SFM alone and approached those in control conditions, while performance metrics after cold storage in SFM alone or cold storage for 48 h were both significantly reduced. A serum-free medium supplemented with Def allowed hepatocyte spheroids to tolerate 24 h of cold storage with less than 10% loss in viability and functionality. Further research is warranted to optimize a solution for extended cold storage of hepatocyte spheroids.

Liver dialysis in acute-on-chronic liver failure: current and future perspectives

Patients with acute-on-chronic liver failure (ACLF) are known to have a very high mortality rate as the majority of these patients succumb to multiorgan failure. Liver transplant remains the only option for these patients; however, there are problems with its availability, cost and also the complications and side effects associated with immunosuppression. Unlike advanced decompensated liver disease, there is a potential for hepatic regeneration and recovery in patients with ACLF. A liver support system, cell or non-cell based, logically is likely to provide temporary functional support until the donor liver becomes available or the failing liver survives the onslaught of the acute insult and spontaneously regenerates. Understanding the pathogenesis of liver failure and regeneration is essential to define the needs for a support system. Removal of hepatotoxic metabolites and inhibitors of hepatic regeneration by liver dialysis, a non-cell-based hepatic support, could help to provide a suitable microenvironment and support the failing liver. The current systems, i.e., MARS and Prometheus, have failed to show survival benefits in patients with ACLF based on which newer devices with improved functionality are currently under development. However, larger randomized trials are needed to prove whether these devices can enable restoration of the complex dysregulated immune system and impact organ failure and mortality in these patients.

Acute-on-chronic liver failure: a review

There is no universally accepted definition of acute-on-chronic liver failure; however, it is recognized as an entity characterized by decompensation from an underlying chronic liver disease associated with organ failure that conveys high short-term mortality, with alcoholism and infection being the most frequent precipitating events. The pathophysiology involves inflammatory processes associated with a trigger factor in susceptible individuals (related to altered immunity in the cirrhotic population). This review addresses the different definitions developed by leading research groups, epidemiological and pathophysiological aspects, and the latest treatments for this entity.

Imbalance between circulating CD4+ regulatory T and conventional T lymphocytes in patients with HBV-related acute-on-chronic liver failure

BACKGROUND & AIMS

The important pathophysiological role of immune dysfunction, especially innate immune dysfunction in patients with acute-on-chronic liver failure (ACLF), has been investigated in recent years, but dysregulation of adaptive immunity remains poorly elucidated. The aim of this study was to (i) determine the CD3(+) T-lymphocyte count and the balance between CD4(+) regulatory T (Tregs) and conventional T cells (Tconv) in hepatitis B virus (HBV)-related ACLF patients; (ii) analyse the frequencies of Tregs subpopulations; and (iii) assess the suppressive potency of CD4(+) Tregs and each fraction.

METHODS

We enrolled 20 HBV-ACLF patients, 10 septic shock subjects, 20 chronic hepatitis B (CHB) patients and 20 healthy volunteers (HC). Based on flow cytometry, we performed the absolute counting of circulating T lymphocytes and phenotyping of CD4(+) Tregs and quantified the effects of Tregs and each subpopulation on Tconv proliferation by CFSE staining.

RESULTS

Compared with CHB patients and HC, we observed an equal reduction in peripheral T subsets in HBV-ACLF and septic shock subjects; the number of CD4(+) Tregs remained unchanged and the Tconv count declined, promoting elevation of the Treg-to-Tconv ratio. The frequencies of Treg-II and -III were elevated in HBV-ACLF. Functional studies showed that the suppressive capacity of Tregs was preserved in the HBV-ACLF group and Treg-II came first.

CONCLUSIONS

Similar to septic shock subjects, in HBV-ACLF patients there exists a reduction in CD4(+) T lymphocytes, predominantly CD4(+) Tconv, and the development of suppressive CD4(+) Tregs greatly prevails over Tconv, constituting important characteristics of adaptive immune dysfunction of HBV-ACLF.

Early predictor of mortality due to irreversible posthepatectomy liver failure in patients with hepatocellular carcinoma

BACKGROUND

Although mortality after liver resection has declined, posthepatectomy liver failure (PHLF) remains a major cause of operative mortality. To date there is not consensus on a definition for PHLF. However, there have been many efforts to define PHLF causing operative mortality. In the present study we sought to identify early predictors of death from irreversible PHLF.

MATERIALS AND METHODS

We retrospectively analyzed the medical records of 359 patients with hepatocellular carcinoma who underwent liver resection between March 2000 and December 2010. Various biochemical parameters from postoperative days (POD) 1, 3, 5, and 7 were analyzed and compared with the "50-50" criterion.

RESULTS

Operative mortality was 4.7 %. Prothrombin time (PT) <65 % and bilirubin ≥ 38 μmol/L on POD 5 showed the only significant difference as compared with "50-50" criterion. The new combination of bilirubin level and the international normalized ratio showed higher sensitivity, area under the curve, as well as similar accuracy (sensitivity 78.6 vs. 28.6 %; p = 0.002; area under the curve 0.8402 vs. 0.6396; p = 0.00176; accuracy 88.6 vs. 93.4 %; p = 0.090). Multivariate analysis revealed the combination of PT <65 % and bilirubin ≥ 38 μmol/L on POD 5 to be the only independent predictive factor of mortality (odds ratio, 82.29; 95 % confidence interval 8.69-779.64; p < 0.001).

CONCLUSIONS

In patients with chronic liver disease who will undergo liver resection the combination of PT <65 % and bilirubin ≥ 38 μmol/L on POD 5 may be a more sensitive predictor than the "50-50" criterion of mortality from PHLF. Although it needs to validated by prospective study, this measure may be applied to select patients receiving artificial liver supports or liver transplantation.

Efficient removal of serum bilirubin by a novel artificial liver support system using albumin convection: a pilot study

BACKGROUND/AIMS

To compare the efficacy of a new artificial liver support system, fractionated plasma separation and adsorption integrated with hemofiltration, with the old system, plasma adsorption.

METHODS

Sixteen patients with acute liver failure each received a first session of treatment using the old system, in which plasma was perfused through an adsorber. They then received a second session using the new system, in which albumin-rich plasma separated using a fraction plasma separator was ultrafiltrated using a hemofilter and perfused through an adsorber before being returned to blood.

RESULTS

The new system had a higher clearance of bilirubin and slower decline of clearance over time. There was a lower reduction ratio of bilirubin, bile acid, urea, and creatinine; longer prolongation of coagulation parameters; and greater decline in albumin level using the old system compared with the new one.

CONCLUSIONS

Use of the novel system results in more efficient removal of toxins and fewer deterious effects than the old system.

Long-term therapy of a patient with summerskill-walshe-tygstrup syndrome by applying prometheus® liver dialysis: a case report

Summerskill-Walshe-Tygstrup syndrome is a rare benign chronic liver disease characterized by recurring cholestasis with jaundice and severe pruritus. Due to insufficient conservative treatment, liver dialysis by Prometheus^® was applied to a 45-year-old female patient with resistant pruritus. Initially, other possible liver diseases were excluded and the patient was treated symptomatically since the diagnosis of Summerskill-Walshe-Tygstrup was stated in 1998. As conservative and endoscopic methods progressively failed to relieve the patient's suffering, Prometheus^® liver dialysis was performed regularly since 2006 at 3-month intervals and successfully led to a decrease in the patient's symptoms. Cholestatic liver enzymes and also serum bile acids could be lowered significantly from an average of 22.5 ± 2.7 to 7.3 ± 1.7 µmol/l. Consequently, Prometheus^® liver dialysis may be a beneficial option for patients with benign recurrent intrahepatic cholestasis suffering from therapy-resistant symptoms and may be used as well as other extracorporeal liver support devices which have already been reported to improve cholestatic pruritus.

Acute-on-chronic liver failure in chronic hepatitis B

Acute-on-chronic liver failure (ACLF) in chronic hepatitis B (CHB) is most commonly caused by acute severe exacerbation of CHB. The pathophysiology of ACLF in CHB is still poorly understood. Despite the identification of important predisposing factors and prognostic markers, ACLF in CHB remains a disease associated with high mortality. The majority of studies using nucleoside analog therapy did not show any significant improvement in survival, although larger prospective studies are needed. Liver transplantation is the definitive treatment for ACLF in CHB. The challenge ahead would be prognosticating cases with favorable or unfavorable outcomes in order to streamline patients for early transplantation or for medical therapy.