Acute-on-chronic liver failure: current concepts on definition, pathogenesis, clinical manifestations and potential therapeutic interventions

The Intestinal Microbiota in the Development of Chronic Liver Disease: Current Status

Chronic liver disease (CLD) is a significant global health burden, leading to millions of deaths annually. The gut-liver axis plays a pivotal role in this context, allowing the transport of gut-derived products directly to the liver, as well as biological compounds from the liver to the intestine. The gut microbiota plays a significant role in maintaining the health of the digestive system. A change in gut microbiome composition as seen in dysbiosis is associated with immune dysregulation, altered energy and gut hormone regulation, and increased intestinal permeability, contributing to inflammatory mechanisms and damage to the liver, irrespective of the underlying etiology of CLD. The aim of this review is to present the current knowledge about the composition of the intestinal microbiome in healthy individuals and those with CLD, including the factors that affect this composition, the impact of the altered microbiome on the liver, and the mechanisms by which it occurs. Furthermore, this review analyzes the effects of gut microbiome modulation on the course of CLD, by using pharmacotherapy, nutrition, fecal microbiota transplantation, supplements, and probiotics. This review opens avenues for the translation of knowledge about gut-liver interplay into clinical practice as an additional tool to fight CLD and its complications.

Landscapes of gut microbiome and bile acid signatures and their interaction in HBV-associated acute-on-chronic liver failure

Introduction

Submassive hepatic necrosis (SMHN, defined as necrosis of 15-90% of the entire liver on explant) is a likely characteristic pathological feature of ACLF in patients with hepatitis B cirrhosis. We aimed to comprehensively explore microbiome and bile acids patterns across enterhepatic circulation and build well-performing machine learning models to predict SMHN status.

Methods

Based on the presence or absence of SMHN, 17 patients with HBV-related end-stage liver disease who received liver transplantation were eligible for inclusion. Serum, portal venous blood, and stool samples were collected for comparing differences of BA spectra and gut microbiome and their interactions. We adopted the random forest algorithm with recursive feature elimination (RF-RFE) to predict SMHN status.

Results

By comparing total BA spectrum between SMHN (-) and SMHN (+) patients, significant changes were detected only in fecal (P = 0.015). Compared with the SMHN (+) group, the SMHN (-) group showed that UDCA, 7-KLCA, 3-DHCA, 7-KDCA, ISOLCA and α-MCA in feces, r-MCA, 7-KLCA and 7-KDCA in serum, γ-MCA and 7-KLCA in portal vein were enriched, and TUDCA in feces was depleted. PCoA analysis showed significantly distinct overall microbial composition in two groups (P = 0.026). Co-abundance analysis showed that bacterial species formed strong and broad relationships with BAs. Among them, Parabacteroides distasonis had the highest node degree. We further identified a combinatorial marker panel with a high AUC of 0.92.

Discussion

Our study demonstrated the changes and interactions of intestinal microbiome and BAs during enterohepatic circulation in ACLF patients with SMHN. In addition, we identified a combinatorial marker panel as non-invasive biomarkers to distinguish the SMHN status with high AUC.

Synergistic effect of docosahexaenoic acid or conjugated linoleic acid with caffeic acid on ameliorating oxidative stress of HepG2 cells

Exploring the synergistic effect of docosahexaenoic acid (DHA) or conjugated linoleic acid (CLA) with caffeic acid (CA) on ameliorating oxidative stress, thereby introducing CA to DHA or CLA will contribute significantly to enhance the bioactivity. We observed that DHA or CLA with CA promoted the recovery of intact individual morphology and the decline of cavities inside the nucleus and apoptosis under the observation of confocal laser scanning microscopy and fluorescent inverted microscope. The activity of intracellular antioxidant enzymes catalase (CAT) and glutathione peroxidase (GSH-Px), lactate dehydrogenase (LDH) leakage, pyruvate and malondialdehyde and reactive oxygen species (ROS), cellular morphology, and cell cycle were analyzed. Our results showed that DHA or CLA with CA enhanced the activity of CAT and GSH-Px, decreased LDH leakage and the number of apoptotic, significantly inhibited (ROS-induced cellular injury. Cell arrest in G1 and G2 phase during cell mitosis was reduced by the measurement of flow cytometry. DHA or CLA combined with CA could markedly strengthen the free radical scavenging and endogenous antioxidant defense capacity on HepG2 cells. This study provides a new direction in the application of synergies to antioxidant compounds. PRACTICAL APPLICATION: Caffeic acid (CA) can synergize with docosahexaenoic acid (DHA) or conjugated linoleic acid (CLA) to enhance antioxidant capacity. This study highlighted an effect of ameliorating oxidative stress injury DHA or CLA with CA on HepG2 cells. The data indicated that DHA or CLA with CA might be used to relieve oxidative stress damage.

The efficacy and safety of methylprednisolone in hepatitis B virus-related acute-on-chronic liver failure: a prospective multi-center clinical trial

BACKGROUND

Hepatitis B virus-related acute-on-chronic liver failure (HBV-ACLF) is a severe condition with high mortality due to lack of efficient therapy. Until now, the use of methylprednisolone (MP) in HBV-ACLF is still controversial. We aimed to evaluate the efficacy and safety of MP in HBV-ACLF.

METHODS

Totally 171 HBV-ACLF patients from three medical centers were randomly allocated into MP group (83 patients treated with MP intravenously guttae for 7 days plus standard treatment: 1.5 mg/kg/day [day 1-3], 1 mg/kg/day [day 4-5], and 0.5 mg/kg/day [day 6-7]) and control group (88 patients treated with standard treatment). The primary endpoints were 6-month mortality and prognostic factors for 6-month survival. The survival time, cause of death, adverse events, liver function, and HBV DNA replication were analyzed.

RESULTS

The 6-month mortality was significantly lower in MP group than control group [32.4% vs. 42.5%, P = 0.0037]. MP treatment was an independent prognostic factor for 6-month survival [HR (95% CI) 0.547(0.308-0.973); P = 0.040]. Factors associated with reduced 6-month mortality in MP group included HBV DNA and lymphocyte/monocyte ratio (LMR) (P < 0.05). Based on ROC curve, LMR+MELD had a better predictive value for prognosis of HBV-ACLF under MP treatment. No significant difference in HBV DNA replication was observed between groups (P > 0.05).

CONCLUSIONS

MP therapy is an effective and safe clinical strategy in HBV-ACLF, increasing the 6-month survival rate. Clinical trials registered at http://www.chictr.org.cn as ChiCTR-TRC-13003113 registered on 16 March 2013.

Gut Microbiota and Liver Injury (II): Chronic Liver Injury

Chronic liver injury mainly comprises viral hepatitis, fatty liver disease, autoimmune hepatitis, cirrhosis and liver cancer. It is well established that gut microbiota serves as the key upstream modulator for chronic liver injury progression. Indeed, the term "gut-liver axis" was mostly applied for chronic liver injury. In the current chapter, we will summarize the relationship between gut microbiota and chronic liver injury, including the interaction between them based on latest clinic and basic research.

Inhibition of glutamine synthetase in monocytes from patients with acute-on-chronic liver failure resuscitates their antibacterial and inflammatory capacity

OBJECTIVE

Acute-on-chronic liver failure (ACLF) is associated with dysfunctional circulating monocytes whereby patients become highly susceptible to bacterial infections. Here, we identify the pathways underlying monocyte dysfunction in ACLF and we investigate whether metabolic rewiring reinstates their phagocytic and inflammatory capacity.

DESIGN

Following phenotypic characterisation, we performed RNA sequencing on CD14⁺CD16^- monocytes from patients with ACLF and decompensated alcoholic cirrhosis. Additionally, an in vitro model mimicking ACLF patient-derived features was implemented to investigate the efficacy of metabolic regulators on monocyte function.

RESULTS

Monocytes from patients with ACLF featured elevated frequencies of interleukin (IL)-10-producing cells, reduced human leucocyte antigen DR isotype (HLA-DR) expression and impaired phagocytic and oxidative burst capacity. Transcriptional profiling of isolated CD14⁺CD16^- monocytes in ACLF revealed upregulation of an array of immunosuppressive parameters and compromised antibacterial and antigen presentation machinery. In contrast, monocytes in decompensated cirrhosis showed intact capacity to respond to inflammatory triggers. Culturing healthy monocytes in ACLF plasma mimicked the immunosuppressive characteristics observed in patients, inducing a blunted phagocytic response and metabolic program associated with a tolerant state. Metabolic rewiring of the cells using a pharmacological inhibitor of glutamine synthetase, partially restored the phagocytic and inflammatory capacity of in vitro generated- as well as ACLF patient-derived monocytes. Highlighting its biological relevance, the glutamine synthetase/glutaminase ratio of ACLF patient-derived monocytes positively correlated with disease severity scores.

CONCLUSION

In ACLF, monocytes feature a distinct transcriptional profile, polarised towards an immunotolerant state and altered metabolism. We demonstrated that metabolic rewiring of ACLF monocytes partially revives their function, opening up new options for therapeutic targeting in these patients.

Evaluating the best empirical antibiotic therapy in patients with acute-on-chronic liver failure and spontaneous bacterial peritonitis

BACKGROUND/AIMS

Spontaneous bacterial peritonitis (SBP) is a life-threatening complication of advanced cirrhosis. By studying the susceptibility of isolated organisms and analyzing empirical antibiotic therapy combined with clinical outcomes, we aimed to find an improved empirical antibiotic therapy by considering the individual acute-on-chronic liver failure (ACLF) grade for patients with or without sepsis.

METHODS

Clinical outcomes of 182 patients were assessed retrospectively with multivariable regression analysis. Each of the 223 isolates was individually evaluated regarding susceptibility results and intrinsic resistances.

RESULTS

Piperacillin/tazobactam had the highest antimicrobial susceptibility among monotherapies/fixed combinations, which was significantly lower than combination therapies such as meropenem-linezolid (75.3% vs. 98.5%, P < 0.001). The sensitivity of pathogens to empirical antibiotic therapy correlated with significantly lower inpatient mortality (18.9% vs. 37.0%, P = 0.018), shorter inpatient stay (16.3 ± 10.2 vs. 26.4 ± 21.0 days, P = 0.053) and shorter intensive care treatment (2.1 ± 4.5 vs. 7.9 ± 15.4 days, P = 0.016). The largest difference of mortality was observed in patients with ACLF grade 3 (54.5% vs. 73.1% [sensitive vs. non-sensitive]).

CONCLUSION

All SBP patients benefited from efficient empirical antibiotic therapy, regarding the reduced inpatient mortality and complications. For SBP patients with ACLF grade 3 without sepsis, the combination therapy with meropenem-linezolid may be suitable considering the susceptibility results and the concentration in the peritoneal cavity.

Receptor-Interacting Protein Kinase 3 (RIPK3) mRNA Levels Are Elevated in Blood Mononuclear Cells of Patients with Poor Prognosis of Acute-on-Chronic Hepatitis B Liver Failure

Necroptosis refers to a programmed form of necrosis, which involves the receptor-interacting protein kinase 3 (RIPK3) and mixed lineage kinase domain-like protein (MLKL). In this study, to investigate the role of necroptosis in the pathogenesis of acute-on-chronic hepatitis B liver failure (ACHBLF), we retrospectively analyzed 122 patients with ACHBLF, 131 patients with chronic hepatitis B (CHB), and 35 healthy controls (HCs). Using quantitative real-time polymerase chain reaction (RT-qPCR), we measured RIPK3 mRNA levels in peripheral blood mononuclear cells (PBMCs). ELISA was performed to measure the serum levels of MLKL, TNF-α and caspase-8. We found that RIPK3 mRNA levels were significantly higher in patients with ACHBLF than those with CHB or HCs. RIPK3 mRNA levels in patients with ACHBLF were positively correlated with serum levels of TNF-α or MLKL and negatively correlated with caspase-8 levels. Univariate and multivariate analysis revealed that RIPK3 mRNA level was predictive of 3-month mortality of ACHBLF. The area under receiver operating characteristic curve (AUC) of RIPK3 mRNA levels was 0.810 (95% CI: 0.729-0.876), which was higher than that of MELD scores (0.766, 95% CI: 0.681-0.838). The optimal cut-off point of 8.81 was determined for RIPK3 mRNA levels, which showed a sensitivity of 80.7% and a negative predictive value of 80.4%. These results indicate that elevated RIPK3 mRNA levels in PBMCs are associated with poor prognosis of ACHBLF. We thus propose that necroptosis may play an important role in pathogenesis of ACHBLF.

Acute-on-chronic liver failure: consensus recommendations of the Asian Pacific association for the study of the liver (APASL): an update

The first consensus report of the working party of the Asian Pacific Association for the Study of the Liver (APASL) set up in 2004 on acute-on-chronic liver failure (ACLF) was published in 2009. With international groups volunteering to join, the "APASL ACLF Research Consortium (AARC)" was formed in 2012, which continued to collect prospective ACLF patient data. Based on the prospective data analysis of nearly 1400 patients, the AARC consensus was published in 2014. In the past nearly four-and-a-half years, the AARC database has been enriched to about 5200 cases by major hepatology centers across Asia. The data published during the interim period were carefully analyzed and areas of contention and new developments in the field of ACLF were prioritized in a systematic manner. The AARC database was also approached for answering some of the issues where published data were limited, such as liver failure grading, its impact on the 'Golden Therapeutic Window', extrahepatic organ dysfunction and failure, development of sepsis, distinctive features of acute decompensation from ACLF and pediatric ACLF and the issues were analyzed. These initiatives concluded in a two-day meeting in October 2018 at New Delhi with finalization of the new AARC consensus. Only those statements, which were based on evidence using the Grade System and were unanimously recommended, were accepted. Finalized statements were again circulated to all the experts and subsequently presented at the AARC investigators meeting at the AASLD in November 2018. The suggestions from the experts were used to revise and finalize the consensus. After detailed deliberations and data analysis, the original definition of ACLF was found to withstand the test of time and be able to identify a homogenous group of patients presenting with liver failure. New management options including the algorithms for the management of coagulation disorders, renal replacement therapy, sepsis, variceal bleed, antivirals and criteria for liver transplantation for ACLF patients were proposed. The final consensus statements along with the relevant background information and areas requiring future studies are presented here.

Antiviral Therapy for AECHB and Severe Hepatitis B (Liver Failure)

This chapter describes the principles of antiviral therapy, treatment strategies, medications and recommendations for AECHB, HBV-ACLF, HBV-related liver cirrhosis, HBV-related HCC, and liver transplantation.

Severe exacerbation of chronic hepatitis B is closely related to continuous HBV replication. Therefore, inhibiting HBV replication to reduce viral load may block disease progression and improve the quality of life of these patients. ETV or TDF has been recommend first-line drug for the treatment of AECHB.

A hyperactive immune response due to continuous HBV replication is the main mechanism for development of severe hepatitis B. In addition to comprehensive treatment, early administration of potent nucleoside analogs can rapidly reduce HBV DNA concentration, relieve immune injury induced by HBV, and reduce liver inflammation and patient mortality. Antiviral agents have become important in the treatment of severe exacerbation of chronic hepatitis B.

Long-term antiviral treatment with nucleoside analogs can delay or reverse the progress of liver cirrhosis. Virologic response, viral resistance and adverse drug reactions should be closely monitored during treatment. The treatment should be optimized for maximum effect based on each patient’s responses.

Effective antiviral therapy can suppress HBV replication and reduce the incidence of HBV-related HCC. Patients with HBV-related HCC should receive individualized and optimal multidisciplinary comprehensive treatment. Anti-viral drugs with high efficacy, low resistance and low adverse drug reactions should be selected to improve the patient’s quality of life and prolong survival time.

Methods to prevent HBV reinfection after liver transplantation include passive immunization (HBIG), antiviral treatment (nucleoside analogs) and active immunization (hepatitis B vaccine).

Clinical trials involving sequential combination therapy with NUC and Peg-IFN have shown statistically significant decline in HBsAg levels on treatment and high rates of sustained post-treatment serologic response. Combination therapy with novel DAA and immunotherapeutic approach may hold promise to overcome both cccDNA persistence and immune escape, representing a critical step towards HBV cure.

Systemic Inflammation and Acute-on-Chronic Liver Failure: Too Much, Not Enough

ACLF is a specific, but complex and multifactorial form of acute decompensation of cirrhosis and is characterized by an extraordinary dynamic natural course, rapidly evolving organ failure, and high short-term mortality. Dysbalanced immune function is central to its pathogenesis and outcome with an initial excessive systemic inflammatory response that drives organ failure and mortality. Later in its course, immuno-exhaustion/immunoparalysis prevails predisposing the patient to secondary infectious events and reescalation in end-organ dysfunction and mortality. The management of patients with ACLF is still poorly defined. However, as its pathophysiology is gradually being unravelled, potential therapeutic targets emerge that warrant further study such as restoring or substituting albumin via plasma exchange or via albumin dialysis and evaluating usefulness of TLR4 antagonists, modulators of gut dysbiosis (pre- or probiotics), and FXR-agonists.

Prediction model of the progression of patients with acute deterioration of hepatitis B virus-related chronic liver disease to acute-on-chronic liver failure

This study aimed to establish a new model for predicting acute-on-chronic liver failure (ACLF) (defined by the Chinese Medical Association), which potentially occurs among patients with acute deterioration (AD) of hepatitis B virus (HBV)-related chronic liver disease (CLD).A total of 754 patients with AD of HBV-related CLD (total bilirubin (TBIL) > 51.3 μmol/L and prothrombin activity (PTA) < 60%, 40% < PTA < 60% when TBIL ≥ 171.1 μmol/L) were retrospectively analyzed and divided into a training cohort (580 patients) and a validation cohort (174 patients). The ACLF occurrence probability of these patients was statistically analyzed within 4 weeks. In the training cohort, multivariate logistic regression analysis was performed to determine the independent predictors of ACLF occurrence and to develop a new prediction model. The validation cohort was utilized to verify and evaluate the value of the new prediction model.Within 4 weeks, 9.9% of the patients progressed to ACLF (12.0 ± 6.7 days). The new prediction model was characterized by R = 3.090 + 0.035 × Age (years) - 0.050 × PTA (%) + 0.005 × TBIL (μmol/L) + 0.044 × D/T (%) - 0.072 × Na (mmol/L) + 0.180 × HBV DNA (log10IU/mL). The areas under the receiver operating characteristic curves of the training and validation cohorts in the new model were higher than those in the model for end-stage liver disease.The new prediction model could be used by clinicians to recognize patients with AD of HBV-related CLD with high risks of progressing to ACLF.

Hepatoprotective effect of α-mangostin against lipopolysaccharide/d-galactosamine-induced acute liver failure in mice

The purpose of this study was to investigate the hepatoprotective effect of α-mangostin (α-MG) on lipopolysaccharide/d-galactosamine (LPS/D-GalN)-induced acute liver failure and discover its potential mechanisms in mice. The results showed that α-MG could attenuate LPS/D-GalN-induced liver pathological injury, and decrease the hepatic malondialdehyde (MDA) level, serum alanine aminotransferase (ALT), aspartate transaminase (AST), tumor necrosis factor (TNF-α), interleukin-1β and 6 (IL-1β, IL-6) levels and recovery hepatic glutathione (GSH), superoxide dismutase (SOD), catalase (CAT) activities. The results also indicated that α-MG inhibited LPS/D-GalN-induced toll-like receptor 4 (TLR4) expression and NF-κB activation. In addition, α-MG up-regulated the expressions of Nrf2 and heme oxygenase-1 (HO-1). In conclusion, the results indicated that α-MG could protect against LPS/D-GalN-induced liver failure by activating Nrf2 to induce antioxidant defense and inhibiting TLR4 signaling pathway to induce anti-inflammatory effect.

Comparison of five different scoring models for predicting short-term mortality in patients with alcohol-related acute-on-chronic liver failure

AIM

To compare the performance of age, bilirubin, INR, and creatinine (ABIC), Maddrey's discriminant function (MDF), model for end-stage liver disease (MELD), chronic liver failure-sequential organ failure assessment (CLIF-SOFA), and Child-Turcotte-Pugh (CTP) in predicting short-term mortality in patients with alcohol-related acute-on-chronic liver failure (ACLF).

METHODS

There were 462 consecutive patients with live failure treated from August 2005 to June 2017 at Tianjin Third Central Hospital, of whom 152 with alcohol-related ACLF were finally enrolled in this study according to the inclusion criteria and exclusion criteria. We divided patients into either group A or group B. Patients in group A met the criteria of Asian Pacific Association for the Study of the Liver but did not met the criteria of European Association for the Study of the Liver-Chronic Liver Failure (EASL-CLIF), and patients in group B met the criteria of EASL-CLIF on admission. The performance of different scoring models in predicting short-term mortality was assessed using the area under the receiver operating characteristic curve (AUC-ROC).

RESULTS

The 28-d mortality rate was 19% in group A and 50% in group B (P = 0.002). In group A, the AUC of CLIF-SOFA for predicting the 28-d mortality was highest (0.889), followed by MELD (0.761), MDF (0.738), ABIC (0.718), and CTP (0.671), and there was a significant difference between CTP and the others. In group B, the AUC of CLIF-SOFA was 0.916, followed by MELD (0.804), MDF (0.770), ABIC (0.729), and CTP (0.647), and there was a significant difference between CLIF-SOFA and the others and between CTP and the others.

CONCLUSION

The five scoring systems could all predict the short-term prognosis of the two groups of patients. However, CLIF-SOFA performs well compared to the others, regardless of patients in group A or group B.

Disruption of the gut-liver axis in the pathogenesis of acute-on-chronic liver failure

Acute-on-chronic liver failure (ACLF) is characterized by organ failure mediated by acute decompensation of cirrhosis. Recent studies have highlighted the importance of the gut-liver axis (GLS) and its association with ACLF pathogenesis. In this review, we discuss the mechanisms related to the alteration of the GLA and their involvement in ACLF pathogenesis and suggest some possible therapeutic options that could modulate the GLA dysfunction. This knowledge may provide information useful for the design of therapeutic strategies for gut dysbiosis and its complications in ACLF.

Systemic inflammatory response syndrome in acute-on-chronic liver failure: Relevance of 'golden window': A prospective study

BACKGROUND AND AIM

Systemic inflammatory response syndrome (SIRS) is an early marker of sepsis and ongoing inflammation and has been reported in large proportion of acute-on-chronic liver failure (ACLF) patients. Whether sepsis is the cause or the result of liver failure is unclear and is vital to know. To address this, the study investigated the course and outcome of ACLF patients without SIRS/sepsis.

METHODS

Consecutive ACLF patients were monitored for the development of SIRS/sepsis and associated complications and followed till 90 days, liver transplant or death.

RESULTS

Of 561 patients, 201 (35.8%) had no SIRS and 360 (64.2%) had SIRS with or without infection. New onset SIRS and sepsis developed in 74.6% and 8% respectively in a median of 7 (range 4-15) days, at a rate of 11% per day. The cumulative incidence of new SIRS was 29%, 92.8%, and 100% by days 4, 7, and 15. Liver failure, that is, bilirubin > 12 mg/dL (odds ratio [OR] = 2.5 [95% confidence interval {CI} = 1.05-6.19], P = 0.04) at days 0 and 4, and renal failure at day 4 (OR = 6.74 [95%CI = 1.50-13.29], P = 0.01), independently predicted new onset SIRS. Absence of SIRS in the first week was associated with reduced incidence of organ failure (20% vs 39.4%, P = 0.003), as was the 28-day (17.6% vs 36%, P = 0.02) and 90-day (27.5% vs 51%,P = 0.002) mortality. The 90-day mortality was 61.6% in the total cohort and that for those having no SIRS and SIRS at presentation were 42.8% and 65%, respectively (P < 0.001).

CONCLUSION

Liver failure predicts the development of SIRS. New onset SIRS in the first week is an important determinant of early sepsis, organ failure, and survival. Prompt interventions in this 'golden window' before development of sepsis may improve the outcome of ACLF.

Acute-on-chronic liver failure: recent update

Acute on chronic liver failure (ACLF) was first described in 1995 as a clinical syndrome distinct to classic acute decompensation. Characterized by complications of decompensation, ACLF occurs on a background of chronic liver dysfunction and is associated with high rates of organ failure and significant short-term mortality estimated between 45% and 90%. Despite the clinical relevance of the condition, it still remains largely undefined with continued disagreement regarding its precise etiological factors, clinical course, prognostic criteria and management pathways. It is concerning that, despite our relative lack of understanding of the condition, the burden of ACLF among cirrhotic patients remains significant with an estimated prevalence of 30.9%. This paper highlights our current understanding of ACLF, including its etiology, diagnostic and prognostic criteria and pathophysiology. It is evident that further refinement of the ACLF classification system is required in order to detect high-risk patients and improve short-term mortality rates. The field of metabolomics certainly warrants investigation to enhance diagnostic and prognostic parameters, while the use of granulocyte-colony stimulating factor is a promising future therapeutic intervention for patients with ACLF.

Toward a Better Definition of Acute-on-Chronic Liver Failure

Acute-on-chronic liver failure (ACLF) has been defined differently in the East and West. The definitions given by Asian Pacific association for the study of liver (APASL) and American association for the study of liver (AASLD) and European association for the study of liver (EASL) working group have fundamental deficiencies and contradictions and do not encompass all patients with ACLF seen in the East and West. Although the World Gastroenterology Organisation (WGO) working party attempted to provide an improved definition but this too is not appropriate. In this article, we have compared the various definitions of ACLF given by APASL, EASL-AASLD and WGO and suggest a comprehensive definition for prospective collection of data on ACLF.

High promoter methylation levels of glutathione-S-transferase M3 predict poor prognosis of acute-on-chronic hepatitis B liver failure

AIM

This study aimed to evaluate the prognostic value of glutathione-S-transferase M3 (GSTM3) gene promoter methylation in patients with acute-on-chronic hepatitis B liver failure (ACHBLF).

METHODS

A total of 119 patients with ACHBLF, 60 patients with chronic hepatitis B and 30 healthy controls were enrolled. We used a quantitative methylation detection technique, MethyLight, to examine the methylation levels of GSTM3 in peripheral blood mononuclear cells.

RESULTS

The GSTM3 methylation level was significantly higher in patients with ACHBLF than those in patients with chronic hepatitis B and healthy controls (both P < 0.05). In patients with ACHBLF, GSTM3 methylation level percentage of methylated reference (PMR) positively correlated with total bilirubin, international normalized ratio, and Model for End-stage Liver Disease (MELD) score, and negatively correlated with prothrombin activity and albumin (all P < 0.05). The PMR for GSTM3 of non-survivors was significantly increased compared to that of survivors (P < 0.05). Multivariate analysis indicated that GSTM3 methylation level was one of the independent prognostic factors for 3-month mortality of ACHBLF (P = 0.000). The area under the receiver-operator characteristic curve of PMR for GSTM3 in predicting 3-month mortality of ACHBLF was not statistically different from that of MELD score (0.798 vs. 0.716, P = 0.152). However, the area under the curve of PMR for GSTM3 was significantly higher than that of MELD score in predicting 1-month mortality (0.887 vs. 0.737, P = 0.020).

CONCLUSION

Promoter methylation levels of GSTM3 in peripheral blood mononuclear cells closely correlated with disease severity and could be used to predict prognosis of patients with ACHBLF.

Neutrophil-lymphocyte ratio predicts short term mortality in patients with hepatitis B virus-related acute-on-chronic liver failure treated with an artificial liver support system

Aim

Hepatitis B virus-related acute-on-chronic liver failure has high short-term mortality. Artificial liver support systems (ALSS) may improve outcome and avoid liver transplantation, but predicting short-term prognosis in such patients is difficult. This study aimed to determine whether the neutrophil–lymphocyte ratio (NLR), an inflammation marker, predicted mortality in patients treated with ALSS.

Methods

A total of 560 patients with hepatitis B virus-related acute-on-chronic liver failure were enrolled, 338 were treated with ALSS and the others treated with standard of care(SOC). Clinical variables and the NLR were evaluated for prognostic value.

Results

Thirty-day mortality was 28.4% in ALSS and 55.4% in SOC patients. The NLR was lower in survivors than in ALSS or SOC patients who died. Univariate and multivariate analysis found that NLR and the chronic liver failure sequential organ failure assessment scores(CLIF-SOFA) were independently associated with 30-day mortality. Among patients with NLRs ≤ 3, 3–6, and >6, 30-day mortality was 7.7%,23.1%, and 69.2% in ALSS and 25.5%, 50.0%, and 75.0% in SOC patients. Among patients with NLRs ≤ 3 or 3–6, mortality was lower in ALSS than in SOC patients (P < 0.01). Mortality rates of ALSS and SOC patients with NLRs > 6 did not different (P >0.05). The area under curve of NLR and CLIF-SOFA was 0.82 and 0.88 in ALSS group, 0.78 and 0.86 in SOC group. The results suggest that liver function in most patients with NLRs ≤ 3 recovered with ALSS treatment, and patients with NLRs > 6 needed emergency liver transplantation.

Conclusion

NLR was an independent predictor of mortality in ALSS patients and may assist physicians in determining treatment options.

NMR-based urinary profiling of lactulose/mannitol ratio used to assess the altered intestinal permeability in acute on chronic liver failure (ACLF) patients

The article presents a simplified NMR-based protocol for urinary profiling of lactulose/mannitol ratio (LMR) and demonstrates here its utility to assess increased intestinal permeability (IP) in patients with acute on chronic liver failure (ACLF). ACLF is a serious clinical complication associated with chronic liver disease (cirrhosis). The major risk factor in its development is increased IP ('leaky gut'), which has been linked to disease progression and to infectious complications. However, IP has seldom been investigated in patients with ACLF, even though patients frequently report gastrointestinal disorders and associated complications. To this end, we first optimized the NMR-based targeted profiling of urinary metabolites (i.e. actulose, mannitol, and creatinine) and subsequently used this resulted protocol (a) first to evaluate the altered IP in ACLF patients and then (b) to explore its utility for monitoring the treatment response in these patients. The normal profiles were obtained for 7 age and sex matched healthy volunteers. The results revealed that the urinary LMR excretion was significantly higher in ACLF patients compared to normal controls (median ~0.7, range (0.12-2.84), vs median ~0.11, range (0.02-0.28), p < 0.001) suggesting that the ACLF patients' exhibit altered IP. However, the LMR excretion in six clinically improved follow-up ACLF patients was comparable to normal controls indicating restored IP after the treatment. The protocol-as demonstrated here with ACLF-is equally applicable for evaluating IP or mucosal barrier function in other intestinal disorders with reasonable sensitivity and specificity, highlighting its general utility. Copyright © 2016 John Wiley & Sons, Ltd.

Complications in Aneurysmal Subarachnoid Hemorrhage Patients With and Without Subdural Electrode Strip for Electrocorticography

PURPOSE

Patients with aneurysmal subarachnoid hemorrhage (aSAH) frequently develop secondary noninfectious and infectious complications with an important impact on clinical course and outcome. In this study, we report on the rate of typical extracranial and intracranial complications in 30 prospectively enrolled patients with severe aSAH who received a linear subdural recording strip for continuous electrocorticography to detect ictal epileptiform events and spreading depolarizations.

METHODS

The group was compared with 30 retrospectively included patients with aSAH who had not received a subdural recording strip, but were treated during the same period. The control group was matched according to an aSAH grading system, sex, and establishment of external ventricular drainage, but could not be matched according to aneurysm treatment and focal brain lesions such as initial intracerebral hemorrhages.

RESULTS

No evidence was found that procedures of the electrocorticography study led to clinically relevant complications. In particular, the subdural strip did not lead to local damage of brain tissue or any increased rate of meningitis/ventriculitis. The median score on the modified Rankin Scale on day 15 was the same in both groups. Minor differences between both groups are explained by the limitations in the study design.

CONCLUSIONS

Our study suggests that neuromonitoring with a subdural recording strip for up to 15 days can be safely performed in patients with aSAH.

Prevalence and risk factors of acute-on-chronic liver failure in a single center from Argentina

AIM

To study the prevalence, characteristics, risk factors and mortality at 28 d of acute-on-chronic liver failure (ACLF).

METHODS

A total of 100 cirrhotic patients admitted to our hospital for more than one day were included during the period between June 2013 and December 2015. We used the European Association for the Study of the Liver-Chronic Liver Failure-Consortium diagnostic criteria for ACLF, considering it as the acute decompensation of cirrhosis associated with the presence of one or more organ failure. For the diagnosis of organic failure the Chronic Liver Failure-Sequential Organ Failure Assessment score was used. Our population was divided into patients with and without ACLF. Clinical characteristics, presence of precipitating events, potential risk factors for developing ACLF and causes of mortality were analyzed. Mortality at 28 d was evaluated.

RESULTS

Twenty-nine patients (29%) developed ACLF criteria. Alcoholism, detected in 58 patients (58%), was the major etiological agent of cirrhosis. Bacterial infections were recognized as a precipitating event in 41.3% of cases and gastrointestinal bleeding in 27.5%. No precipitating event was identifiable in 27.5% of patients with ACLF. Comparing patients with and without ACLF, statistically significant risk factors were: Child Pugh score 10.2 ± 2.1 vs 8.4 ± 1.6 (P ˂ 0.0001), MELD score 20.7 ± 8.5 vs 12.3 ± 4 (P ˂ 0.0001), presence of ascites 27 (93%) vs 43 (60.5%) (P = 0.001), leukocytosis 15300 ± 8033 per cubic millimeter vs 10770 ± 5601 per cubic millimeter (P ˂ 0.0001), and high plasma levels of C reactive protein values 50.9 ± ​​46.4 mg/L vs 28.6 ± 23.4 mg/L (P ˂ 0.0019). Mortality rate was 62% (18 patients) vs 5.6% (4 patients), respectively (P < 0.0001).

CONCLUSION

We observed that the ACLF is a frequent entity in this group of patients and has a significantly higher mortality rate.

Reviewing the diagnostic criteria for acute-on-chronic liver failure

For over 20 years, acute-on-chronic liver failure (ACLF) has taken multiple definitions and/or classifications. The definition outlines the acute and chronic insults to include a homogenous patient group with liver failure and an expected outcome in a specific time frame. Early and accurate diagnosis is essential as this inflammation of the liver may tilt the balance of liver destruction and regeneration adversely. Various factors such as superadded systemic sepsis, liver reserve, cause of primary chronic liver disease, state of immune system or the state of gut microbial flora might determine the ultimate prognosis. Areas covered: To date, there has been no universally accepted definition of ACLF. In this review, we discuss the strengths and weaknesses, controversies and basis for early identification and accurate diagnosis of ACLF. PubMed and Google scholar database searches were conducted, search terms included 'acute on chronic liver failure,' 'ACLF,' and 'diagnostic criteria.' Expert commentary: With recent advances in the management of advanced cirrhosis, research will gradually shift towards ACLF in the near future, focusing on the pathogenesis, new treatment options and improving survival. Once we improve understanding of this syndrome, newer definitions will evolve, thereby enabling earlier diagnosis and novel therapeutic avenues.

Acute-on-chronic Liver Failure

Acute-on-chronic liver failure (ACLF) is a distinct entity that differs from acute liver failure and decompensated cirrhosis in timing, presence of treatable acute precipitant, and course of disease, with a potential for self-recovery. The core concept is acute deterioration of existing liver function in a patient of chronic liver disease with or without cirrhosis in response to an acute insult. The insult should be a hepatic one and presentation in the form of liver failure (jaundice, encephalopathy, coagulopathy, ascites) with or without extrahepatic organ failure in a defined time frame. ACLF is characterized by a state of deregulated inflammation. Initial cytokine burst presenting as SIRS, progression to CARS and associated immunoparalysis leads to sepsis and multi-organ failure. Early identification of the acute insult and mitigation of the same, use of nucleoside analogue in HBV-ACLF, steroid in severe alcoholic hepatitis, steroid in severe autoimmune hepatitis and/or bridging therapy lead to recovery, with a 90-day transplant-free survival rate of up to 50 %. First-week presentation is crucial concerning SIRS/sepsis, development, multiorgan failure and consideration of transplant. A protocol-based multi-disciplinary approach including critical care hepatology, early liver transplant before multi-organ involvement, or priority for organ allocation may improve the outcome. Presentation with extrahepatic organ involvement or inclusion of sepsis as an acute insult in definition restricts the therapy, i.e., liver transplant or bridging therapy, and needs serious consideration. Augmentation of regeneration, cell-based therapy, immunotherapy, and gut microbiota modulation are the emerging areas and need further research.

Short-term efficacy of treating hepatitis B virus-related acute-on-chronic liver failure based on cold pattern differentiation with hot herbs: A randomized controlled trial

OBJECTIVE

To evaluate the clinical efficacy and safety of Yinchen Zhufu Decoction (, YCZFD) in the treatment of acute-on-chronic liver failure caused by hepatitis B virus (HBV-ACLF) with cold pattern in Chinese medicine (CM).

METHODS

This is a multi-center randomized controlled trial of integrative treatment of CM and Western medicine (WM) for the management of HBV-ACLF patients. A total of 200 HBV-ACLF patients with cold pattern were equally randomly assigned to receive YCZFD and WM (integrative treatment) or WM conventional therapy alone respectively for 4 weeks. The primary end point was the mortality for HBV-ACLF patients. Secondary outcome measures included Model for End-Stage Liver disease (MELD) score, liver biochemical function, coagulation function and complications. Adverse events during treatment were reported.

RESULTS

The mortality was decreased 14.28% in the integrative treatment group compared with WM group (χ(2) =6.156, P=0.013). The integrative treatment was found to signifificantly improve the MELD score (t=2.353, P=0.020). There were statistically signifificant differences in aspartate transaminase, total bilirubin, indirect bilirubin, direct bilirubin and prothrombin time between the two groups (P<0.05 or P<0.01). The complications of ascites (χ(2)=9.033, P=0.003) and spontaneous bacteria peritonitis (χ(2)=4.194, P=0.041) were improved signifificantly in the integrative treatment group. No serious adverse event was reported.

CONCLUSIONS

The integrative treatment of CM and WM was effective and safe for HBV-ACLF patients with cold pattern in CM. The Chinese therapeutic principle "treating cold pattern with hot herbs" remains valuable to the clinical therapy. (Trial registration No. ChiCTR-TRC-10000766).

Predictors of progression into acute-on-chronic liver failure from acute deterioration of pre-existing chronic liver disease

AIM

To compare the prognosis between the patients with progression into acute-on-chronic liver failure (ACLF) from acute deterioration of pre-existing chronic liver disease and patients without this progression, and to determine predictors of this disease progression.

METHODS

We retrospectively analyzed clinical data from 285 patients admitted with acute worsening of pre-existing chronic liver disease within 4 weeks characterized by total bilirubin (TBIL) of 51 μM/L or more and prothrombin activity (PTA) of more than 40% but less than 70%, which did not meet the Asia-Pacific Association for the Study of the Liver criteria for ACLF. Patient survival was estimated by Kaplan-Meier analysis and subsequently compared by log-rank test. Independent predictors of disease progression were determined using univariate analysis and multivariate Cox regression analysis.

RESULTS

The 90-day survival rates significantly worsened in patients with progression into ACLF compared with those without this progression. Baseline TBIL, baseline Model for End-Stage Liver Disease (MELD) score, and the maximum changing rates of PTA level and Child-Turcotte-Pugh (CTP) score were independently associated with progression into ACLF in patients with acute deterioration of pre-existing chronic liver disease.

CONCLUSION

Patients with acute worsening of pre-existing chronic liver disease characterized by TBIL of 51 μM/L or more and PTA of more than 40% but less than 70% should receive aggressive prediction and prevention of ACLF development. Baseline TBIL, baseline MELD score, and the maximum changing rates of PTA level and CTP score may early predict the progression into ACLF.

Impact of chronic hepatitis C on mortality in cirrhotic patients admitted to intensive-care unit

BACKGROUND

Cirrhosis and severe sepsis are factors associated with increased mortality in intensive care unit (ICU), but chronic hepatitis C (CHC) has been less studied in ICU. The aim of this study was to analyze the impact of CHC on the mortality of cirrhotic patients admitted to ICU according to severe sepsis and decompensated cirrhosis.

METHODS

We carried out a retrospective study based on CHC-cirrhotic patients (CHC-group) admitted to ICU (n = 1138) and recorded in the Spanish Minimum Basic Data Set (2005-2010). A control-group (randomly selected cirrhotic patients without HIV, HBV, or HCV infections) was also included (n = 4127). The primary outcome variable was ICU mortality. The cumulative mortality rate on days 7, 30, and 90 in patients admitted to the ICUs was calculated by dividing the number of deaths by the number of patients admitted to the ICU. The adjusted hazard ratio (aHR) for death in the ICU was estimated through a semi-parametric Bayesian model of competing risk.

RESULTS

The CHC-group had a higher cumulative incidence of severe sepsis than the control-group in compensated cirrhosis (37.4 vs. 31.1%; p = 0.024), but no differences between the CHC-group and the control-group in decompensated cirrhosis were found. Moreover, a higher cumulative incidence of severe sepsis was associated with decompensated cirrhosis compared to compensated cirrhosis in the control-group (40.1 vs. 31.1%; p < 0.001) whereas this was not observed in the CHC group (38.1 vs. 37.4%; p = 0.872). The CHC-group had higher cumulative mortality than the control-group by days 7 (47 vs. 41.3%; p < 0.001), 30 (78.5 vs. 73.5%; p < 0.001), and 90 (96.3 vs. 95.9%; p < 0.001). In a competitive risk model, the CHC-group had a higher risk of dying if the ICU course was complicated by severe sepsis (adjusted hazard ratio (aHR) = 1.19; p = 0.003), but no significant values in patients with absence of severe sepsis were found (aHR = 1.09; p= 0.068). When patients were stratified by cirrhosis stage and severe sepsis, CHC patients with compensated cirrhosis had the higher risk of death if they had severe sepsis (aHR = 1.35; p = 0.002). Moreover, the survival was low in patients with decompensated cirrhosis and severe sepsis but we did not find significant differences between CHC-group and control-group.

CONCLUSIONS

CHC was associated with an increased risk of death in cirrhotic patients admitted to ICUs, particularly in patients with compensated cirrhosis and severe sepsis.

Acute-on-chronic liver failure: terminology, mechanisms and management

Acute-on-chronic liver failure (ACLF) is a distinct clinical entity and differs from acute liver failure and decompensated cirrhosis in timing, presence of acute precipitant, course of disease and potential for unaided recovery. The definition involves outlining the acute and chronic insults to include a homogenous patient group with liver failure and an expected outcome in a specific timeframe. The pathophysiology of ACLF relates to persistent inflammation, immune dysregulation with initial wide-spread immune activation, a state of systematic inflammatory response syndrome and subsequent sepsis due to immune paresis. The disease severity and outcome can be predicted by both hepatic and extrahepatic organ failure(s). Clinical recovery is expected with the use of nucleoside analogues for hepatitis B, and steroids for severe alcoholic hepatitis and, possibly, severe autoimmune hepatitis. Artificial liver support systems help remove toxins and metabolites and serve as a bridge therapy before liver transplantation. Hepatic regeneration during ongoing liver failure, although challenging, is possible through the use of growth factors. Liver transplantation remains the definitive treatment with a good outcome. Pre-emptive antiviral agents for hepatitis B before chemotherapy to prevent viral reactivation and caution in using potentially hepatotoxic drugs can prevent the development of ACLF.

A modified prognostic score for critically ill patients with cirrhosis: An observational study

BACKGROUND AND AIMS

It is controversial whether patients with cirrhosis benefit from the intensive care unit (ICU) management. To identify the patients in whom ICU care may offer recovery, this study aimed to determine specific risk factors and to establish a novel prognostic score for 3-month mortality in critically ill patients with cirrhosis.

METHODS

An observational study was performed from August 2008 to May 2014, encompassing 349 critically ill patients with cirrhosis during their ICU stay (a 70% training and 30% validation set).

RESULTS

The overall 3-month mortality rate was 68.1% in training cohort. Prothrombin time, serum bilirubin, use of vasopressors, hepatic encephalopathy, and systemic inflammatory response syndrome at admission were identified as being strongly correlated with the 3-month prognosis. Based on these five variables, a modified score for critically ill cirrhosis (MSCIC) was developed. An increasing MSCIC was significantly correlated with a reduction in the rate of survival (P < 0.001). Moreover, excellent predictive power was found when the MSCIC was used (area under the receiver operating characteristic curve: 0.856 ± 0.047), which was significantly better than the prognostic efficiency of Acute Physiology and Chronic Health Evaluation II (P < 0.001), Model for End-stage Liver Disease (P = 0.02), Simplified Acute Physiology Score (P = 0.023), and the Child-Turcotte-Pugh score (P = 0.01); the MSCIC score was slightly better than that of Chronic Liver Failure-Sequential Organ Failure Assessment (P = 0.068). The similar result was obtained in validation set.

CONCLUSIONS

The MSCIC is an easily adopted tool with a high prognostic efficacy for patients with advanced cirrhosis; MSCIC may act as a supplement to the clinical judgment of physicians when considering the prognosis.

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.

Defining acute-on-chronic liver failure: East, West or Middle ground?

Acute-on-chronic liver failure (ACLF), a newly recognized clinical entity seen in hospitalized patients with chronic liver disease including cirrhosis, is associated with high short- and medium term morbidity and mortality. None of the definitions of ACLF proposed so far have been universally accepted, the two most commonly used being those proposed by the Asia-Pacific Association for the Study of Liver (APASL) and the European Association for the Study of Liver - Chronic Liver Failure (EASL-CLIF) consortium. On paper both definitions and diagnostic criteria appear to be different from each other, reflecting the differences in cut-off values for individual parameters used in diagnosis, the acute insult or precipitating event and the underlying chronic liver disease. Data directly comparing these two criteria are limited, and available studies reveal different outcomes when the two are applied to the same set of patients. However a review of the literature suggests that both definitions do not seem to identify the same set of patients. The definition given by the APASL consortium is easier to apply in day-to-day practice but the EASL-CLIF criteria appear to better predict mortality in ACLF. The World Gastroenterology Organization working party have proposed a working definition of ACLF which will identify patients from whom relevant data can be collected so that the similarities and the differences between the two regions, if any, can be clearly defined.

Submassive hepatic necrosis distinguishes HBV-associated acute on chronic liver failure from cirrhotic patients with acute decompensation

BACKGROUND & AIMS

Distinguishing between acute on chronic liver failure (ACLF) and decompensated liver cirrhosis is difficult due to a lack of pathological evidence.

METHODS

A prospective single-center study investigated 174 patients undergoing liver transplantation due to acute decompensation of hepatitis B virus (HBV)-associated liver cirrhosis. Two groups were distinguished by the presence or absence of submassive hepatic necrosis (SMHN, defined as necrosis of 15-90% of the entire liver on explant). Core clinical features of ACLF were compared between these groups. Disease severity scoring systems were applied to describe liver function and organ failure. Serum cytokine profile assays, gene expression microarrays and immunohistochemical analyzes were used to study systemic and local inflammatory responses.

RESULTS

SMHN was identified in 69 of 174 patients proven to have cirrhosis by histological means. Characteristic features of SMHN were extensive necrosis along terminal hepatic veins and spanning multiple adjacent cirrhotic nodules accompanied by various degrees of liver progenitor cell-derived regeneration, cholestasis, and ductular bilirubinostasis. Patients with SMHN presented with more severely impaired hepatic function, a higher prevalence of multiple organ failure (as indicated by higher CLIF-SOFA and SOFA scores) and a shorter interval between acute decompensation and liver transplantation than those without SMHN (p<0.01 for all parameters). Further analyzes based on serum cytokine profile assays, gene expression microarrays and immunohistochemical analyzes revealed higher levels of anti-inflammatory cytokines in patients with SMHN.

CONCLUSIONS

SMHN is a critical histological feature of HBV-associated ACLF. Identification of a characteristic pathological feature strongly supports that ACLF is a separate entity in end-stage liver disease.

Two sides of one coin: massive hepatic necrosis and progenitor cell-mediated regeneration in acute liver failure

Massive hepatic necrosis is a key event underlying acute liver failure, a serious clinical syndrome with high mortality. Massive hepatic necrosis in acute liver failure has unique pathophysiological characteristics including extremely rapid parenchymal cell death and removal. On the other hand, massive necrosis rapidly induces the activation of liver progenitor cells, the so-called "second pathway of liver regeneration." The final clinical outcome of acute liver failure depends on whether liver progenitor cell-mediated regeneration can efficiently restore parenchymal mass and function within a short time. This review summarizes the current knowledge regarding massive hepatic necrosis and liver progenitor cell-mediated regeneration in patients with acute liver failure, the two sides of one coin.

Liver transplantation reverses hypergammaglobulinemia in patients with chronic hepatic failure

Introduction

Sparse data are available about the effect of therapy methods on antibody levels in patients with liver failure. The aim of this study was to determine serum immunoglobulin concentrations in patients with chronic hepatic failure (CHF), acute- (ALF), or acute-on-chronic liver failure (ACLF) and to evaluate the impact of MARS treatment or liver transplantation (LT) on antibody levels.

Materials and methods

We followed ten patients with ALF, twelve with ACLF and 18 with CHF. Eight patients with ALF and seven with ACLF underwent MARS therapy, whereas the rest received LT. 13 healthy volunteers served as controls. Serum antibody concentrations were measured using ELISA-technique.

Results

Median serum levels of IgA, IgG and IgM were significantly increased in patients with CHF compared to ALF or controls (P < 0.02, P < 0.01, and P < 0.01). IgM and IgG concentrations were also significantly elevated in patients with CHF compared to ACLF (IgM, 3.7 vs. 1 g/L, P < 0.001; IgG, 8.7 vs. 3.1 g/L, P = 0.004). Immediately after LT a significant decrease of IgA (6.9 vs. 3.1 g/L, P = 0.004), IgG (8.7 vs. 5.1 g/L, P = 0.02) and IgM (3.7 vs. 1.8 g/L, P = 0.001) was detected in patients with CHF and antibody levels further decreased the days after LT reaching levels comparable to healthy individuals. MARS treatment had no apparent effect on the immunoglobulin profile in patients with ALF or ACLF.

Conclusion

We provide evidence that LT reverses hypergammaglobulinemia in patients suffering from CHF within one day, which could be explained to a reconstituted hepatic antibody clearance, whereas MARS treatment has no immediate effect on immunoglobulin levels.

Definition of ACLF and inclusion criteria for extra-hepatic organ failure

A prominent characteristic of ACLF is rapid hepatic disease progression with subsequent extra-hepatic organ failure, manifesting as either hepatic coma or hepatorenal syndrome, which is associated with a high mortality rate in a short time. The APASL definition mainly emphasizes recognizing patients with hepatic failure. These patients may subsequently develop extra-hepatic multisystem organ failure leading to high mortality. It is therefore worthwhile to identify the short interim period between the development of liver failure and the onset of extra-hepatic organ failure, the potential therapeutic 'golden window.' Interventions during this period may prevent the development of complications and eventually change the course of the illness. Organ failure is suggested to be a central component of ACLF and may behave differently from chronic decompensated liver disease. Clear and practical criteria for the inclusion of organ failure are urgently needed so that patients with these life-threatening complications can be treated in a timely and appropriate manner. Recent studies suggested that the scoring systems evaluating organ failure [acute physiology, age and chronic health evaluation (APACHE) and sequential organ failure assessment (SOFA) scores] work better than those addressing the severity of liver disease [Child-Pugh and model of end-stage liver disease (MELD) scores] in ACLF. However, a key problem remains that the former scoring systems are reflective of organ failure and not predictive, thus limiting their value as an early indication for intervention.

Dysregulated iron homeostasis is strongly associated with multiorgan failure and early mortality in acute-on-chronic liver failure

Acute-on-chronic liver failure (ACLF) is an ailment with high incidence of multiorgan failure (MOF) and consequent mortality. Dysregulated iron homeostasis and macrophage dysfunction are linked to increased incidence of MOF. We investigated whether a panel of circulating iron-regulating proteins are associated with development of MOF and can predict 15- or 30-day mortality in ACLF patients. One hundred twenty patients with ACLF, 20 patients with compensated cirrhosis, and 20 healthy controls were studied. Relative protein expression profiling was performed in the derivative cohort and confirmed in the validation cohort. A panel of iron regulators and indices were determined. Multiparametric flow cytometry for quantitation of labile iron pool (LIP) was performed. Validation studies confirmed lower serum transferrin (Tf) and ceruloplasmin levels in ACLF and ACLF-MOF, compared to patients with cirrhosis and controls (P < 0.01). Serum iron and ferritin levels were markedly elevated (P < 0.001; P < 0.05) and hepcidin levels were lower (P < 0.001) in ACLF patients with MOF than those without and other groups (P < 0.001). Percentage Tf saturation (%SAT) was higher in ACLF-MOF (39.2%; P < 0.001) and correlated with poor outcome (hazard ratio: 6.970; P < 0.01). Intracellular LIP indices were significantly elevated in the subsets of circulating macrophages in ACLF-MOF, compared to other groups (P < 0.01). Whereas expression of iron-regulatory genes was markedly down-regulated, genes related to endoplasmic reticulum stress, apoptosis, and inflammation were up-regulated in ACLF patients, compared to patients with cirrhosis. Severe dysregulation of autophagy mechanisms was also observed in the former.

CONCLUSIONS

Iron metabolism and transport are severely deranged in ACLF patients and more so in those with MOF. %SAT, circulating hepcidin, and LIP in macrophages correlate with disease severity and %SAT could be used for early prognostication in ACLF patients.

Clinical profile, natural history, and predictors of mortality in patients with acute-on-chronic liver failure (ACLF)

BACKGROUND

Acute-on-chronic liver failure (ACLF) is an increasingly recognized entity encompassing an acute deterioration of liver function in patients with cirrhosis, either secondary to superimposed liver injury or due to extrahepatic precipitating factors such as infection culminating in the end-organ dysfunction. Its main features are reversibility and high short-term mortality due to multiorgan failure (MOF). We aimed to analyze the clinical, laboratory, and etiological predictors of mortality and outcome in patients with ACLF.

METHODS

We evaluated 1215 patients with chronic liver disease; 90 patients met the criteria for ACLF.

RESULTS

The most common cause of underlying chronic liver disease was alcohol, and the most common acute insult (AI) in those patients was superadded alcoholic hepatitis. In all, 50% of all patients died within 30 days (71.1 % within the first 14 days after admission). MOF was the cause of death in 70 % of cases. On multivariate analysis, high serum potassium, serum creatinine higher than 90 µmol/L, and C-reactive protein > 30 mg/L were found to be independent baseline predictors of mortality. APACHE II (Acute Physiology and Chronic Health Evaluation II) score was the best predictor of short-term mortality (area under the curve (AUC), 0.878). MOF was a valuable predictor of mortality (AUC, 0.923); 33 of 35 patients who had MOF at admission died. Presence of positive systemic inflammatory response syndrome criteria at admission was also correlated with in-hospital mortality (AUC, 0.742).

CONCLUSION

ACLF is a serious condition with high short-term mortality. Because ACLF is reversible, it is necessary to identify at-risk patients as soon as possible to treat acute events in a timely manner.

Comparison of current diagnostic criteria for acute-on-chronic liver failure

BACKGROUND AND AIMS

Currently, acute-on-chronic liver failure (ACLF) has been defined differently by Asia-Pacific Association for the Study of the Liver (APASL) and Chinese Medical Association (CMA) in the East, as well as EASL-Chronic Liver Failure (EASL-CLIF) Consortium in the West. This study aimed to compare current different diagnostic criteria for ACLF and to determine predictors of the progression into post-enrollment EASL-CLIF ACLF from ACLF at enrollment defined by APASL alone or by both APASL and CMA but not by EASL-CLIF Consortium.

METHODS

We retrospectively analyzed clinical data from 394 eligible cirrhotic patients fulfilling at least APASL criteria for ACLF at enrollment. Patient survival was estimated by Kaplan-Meier analysis and subsequently compared by log-rank test. Independent predictors of disease progression were determined using univariate analysis and multivariate Cox regression analysis.

RESULTS

The 90-day mortality rate was 13.1% in patients with ACLF at enrollment defined by APASL alone, 25.3% in patients with ACLF at enrollment defined by both APASL and CMA but not EASL-CLIF Consortium, and 59.3% in patients with ACLF at enrollment defined by EASL-CLIF Consortium in addition to APASL. Baseline Chronic Liver Failure-Sequential Organ Failure Assessment (CLIF-SOFA) score, and the maximum rising rates of CLIF-SOFA score, Model for End-Stage Liver Disease-Sodium (MELD-Na) score and total bilirubin were independent predictors of progression into post-enrollment EASL-CLIF ACLF from ACLF at enrollment defined by APASL alone or by both APASL and CMA but not by EASL-CLIF Consortium.

CONCLUSION

Different diagnostic criteria for ACLF caused different patient prognosis. So, it is imperative to formulate a unifying diagnostic criteria for ACLF worldwide, thus attaining early identification and treatment, and eventual improvement in survival of ACLF patients. Baseline CLIF-SOFA score, and the maximum rising rates of CLIF-SOFA score, MELD-Na score and total bilirubin may early predict post-enrollment development of EASL-CLIF ACLF.

The FXR agonist obeticholic acid prevents gut barrier dysfunction and bacterial translocation in cholestatic rats

Bacterial translocation (BTL) drives pathogenesis and complications of cirrhosis. Farnesoid X-activated receptor (FXR) is a key transcription regulator in hepatic and intestinal bile metabolism. We studied potential intestinal FXR dysfunction in a rat model of cholestatic liver injury and evaluated effects of obeticholic acid (INT-747), an FXR agonist, on gut permeability, inflammation, and BTL. Rats were gavaged with INT-747 or vehicle during 10 days after bile-duct ligation and then were assessed for changes in gut permeability, BTL, and tight-junction protein expression, immune cell recruitment, and cytokine expression in ileum, mesenteric lymph nodes, and spleen. Auxiliary in vitro BTL-mimicking experiments were performed with Transwell supports. Vehicle-treated bile duct-ligated rats exhibited decreased FXR pathway expression in both jejunum and ileum, in association with increased gut permeability through increased claudin-2 expression and related to local and systemic recruitment of natural killer cells resulting in increased interferon-γ expression and BTL. After INT-747 treatment, natural killer cells and interferon-γ expression markedly decreased, in association with normalized permeability selectively in ileum (up-regulated claudin-1 and occludin) and a significant reduction in BTL. In vitro, interferon-γ induced increased Escherichia coli translocation, which remained unaffected by INT-747. In experimental cholestasis, FXR agonism improved ileal barrier function by attenuating intestinal inflammation, leading to reduced BTL and thus demonstrating a crucial protective role for FXR in the gut-liver axis.

Magnetic resonance of the brain in chronic and acute liver failure

Brain alterations such as hepatic encephalopathy or brain edema are usually associated with liver failure. The mechanisms that lead to the generation of edema seem to be different depending on the course of liver failure (acute, chronic or acute-on-chronic liver failure). Several neuroimaging methods allow a non-invasive assessment of brain alterations in liver failure. Magnetic resonance has gained more interest due to the ability of giving information about cerebral metabolism using spectroscopy, water distribution by diffusion methods or neuronal connectivity by means of resting state magnetic resonance. These techniques have been applied to experimental models and patients with liver failure to elucidate cerebral pathways involved in the pathogenesis of hepatic encephalopathy. In the future, the development of new magnetic resonance implementations will generate handy tools for the study of the brain and get better understanding of the mechanisms that take place in liver failure. This could be useful for the early diagnosis, as well as for the design of new treatments for cerebral complications of liver failure.

Serum wnt5a is a predictor for the prognosis of acute on chronic hepatitis B liver failure

OBJECTIVES

To find a biomarker to predict the prognosis of acute on chronic hepatitis B liver failure (ACHBLF).

METHODS

Expression gene profiles in wnt pathway were determined in serum from 63 patients with ACHBLF, 60 patients with chronic hepatitis B (CHB) and 30 healthy controls (HCs).

RESULTS

Serum wnt5a concentration of 1.553 ng/ml showed a poor prognosis with a sensitivity of 69.23% and a specificity of 83.33% in ACHBLF patients.

CONCLUSIONS

Serum wnt5a gene expression might be a potential biomarker for predicting the prognosis of ACHBLF.

Liver myofibroblasts from hepatitis B related liver failure patients may regulate natural killer cell function via PGE2

BACKGROUND

Natural killer (NK) cells are abundant in the liver and constitute a major innate immune component that contributes to immune-mediated liver injury. However, few studies have investigated the phenotypes and functions of NK cells involved in hepatitis B related liver failure (LF), and the precise mechanism underlying NK cell regulation is not fully understood.

METHODS

We detected the percentage and function of peripheral NK cells both in hepatitis B related LF patients and healthy volunteers by flow cytometry and isolated the liver myofibroblasts (LMFs) from hepatitis B related LF livers. To determine the possible effects of LMFs on NK cells, mixed cell cultures were established in vitro.

RESULTS

We found a down-regulated percentage of peripheral NK cells in hepatitis B related LF patients, and their NK cells also displayed decreased activated natural cytotoxicity receptors (NCRs) and cytokine production. In a co-culture model, LMFs sharply attenuated IL-2-induced NK cell triggering receptors, cytotoxicity, and cytokine production. The inhibitory effect of LMFs on NK cells correlated with their ability to produce prostaglandin (PG) E2.

CONCLUSION

These data suggest that LMFs may protect against immune-mediated liver injury in hepatitis B related LF patients by inhibiting NK cell function via PGE2.

Acute-on-chronic liver failure: consensus recommendations of the Asian Pacific Association for the Study of the Liver (APASL) 2014

The first consensus report of the working party of the Asian Pacific Association for the Study of the Liver (APASL) set up in 2004 on acute-on-chronic liver failure (ACLF) was published in 2009. Due to the rapid advancements in the knowledge and available information, a consortium of members from countries across Asia Pacific, "APASL ACLF Research Consortium (AARC)," was formed in 2012. A large cohort of retrospective and prospective data of ACLF patients was collated and followed up in this data base. The current ACLF definition was reassessed based on the new AARC data base. These initiatives were concluded on a 2-day meeting in February 2014 at New Delhi and led to the development of the final AARC consensus. Only those statements which were based on the evidence and were unanimously recommended were accepted. These statements were circulated again to all the experts and subsequently presented at the annual conference of the APASL at Brisbane, on March 14, 2014. The suggestions from the delegates were analyzed by the expert panel, and the modifications in the consensus were made. The final consensus and guidelines document was prepared. After detailed deliberations and data analysis, the original proposed definition was found to withstand the test of time and identify a homogenous group of patients presenting with liver failure. Based on the AARC data, liver failure grading, and its impact on the "Golden therapeutic Window," extra-hepatic organ failure and development of sepsis were analyzed. New management options including the algorithms for the management of coagulation disorders, renal replacement therapy, sepsis, variceal bleed, antivirals, and criteria for liver transplantation for ACLF patients were proposed. The final consensus statements along with the relevant background information are presented here.

Mortality of patients infected with HIV in the intensive care unit (2005 through 2010): significant role of chronic hepatitis C and severe sepsis

INTRODUCTION

The combination antiretroviral therapy (cART) has led to decreased opportunistic infections and hospital admissions in human immunodeficiency virus (HIV)-infected patients, but the intensive care unit (ICU) admission rate remains constant (or even increased in some instances) during the cART era. Hepatitis C virus (HCV) infection is associated with an increased risk for hospital admission and/or mortality (particularly those related to severe liver disease) compared with the general population. The aim of this study was to assess the mortality among HIV-infected patients in ICU, and to evaluate the impact of HIV/HCV coinfection and severe sepsis on ICU mortality.

METHODS

We carried out a retrospective study based on patients admitted to ICU who were recorded in the Minimum Basic Data Set (2005 through 2010) in Spain. HIV-infected patients (All-HIV-group (n = 1,891)) were divided into two groups: HIV-monoinfected patients (HIV group (n = 1,191)) and HIV/HCV-coinfected patients (HIV/HCV group (n = 700)). A control group (HIV(-)/HCV(-)) was also included (n = 7,496).

RESULTS

All-HIV group had higher frequencies of severe sepsis (57.7% versus 39.4%; P < 0.001) than did the control group. Overall, ICU mortality in patients with severe sepsis was much more frequent than that in patients without severe sepsis (other causes) at days 30 and 90 in HIV-infected patients and the control group (P < 0.001). Moreover, the all-HIV group in the presence or absence of severe sepsis had a higher percentage of death than did the control group at days 7 (P < 0.001), 30 (P < 0.001) and 90 (P < 0.001). Besides, the HIV/HCV group had a higher percentage of death, both in patients with severe sepsis and in patients without severe sepsis compared with the HIV group at days 7 (P < 0.001) and 30 (P < 0.001), whereas no differences were found at day 90. In a bayesian competing-risk model, the HIV/HCV group had a higher mortality risk (adjusted hazard ratio (aHR) = 1.44 (95% CI = 1.30 to 1.59) and aHR = 1.57 (95% CI = 1.38 to 1.78) for patients with and without severe sepsis, respectively).

CONCLUSIONS

HIV infection was related to a higher frequency of severe sepsis and death among patients admitted to the ICU. Besides, HIV/HCV coinfection contributed to an increased risk of death in both the presence and the absence of severe sepsis.

Scoring systems predict the prognosis of acute-on-chronic hepatitis B liver failure: an evidence-based review

Acute-on-chronic hepatitis B liver failure is a devastating condition that is associated with mortality rates of over 50% and is consequent to acute exacerbation of chronic hepatitis B in patients with previously diagnosed or undiagnosed chronic liver disease. Liver transplantation is the definitive treatment to lower mortality rate, but there is a great imbalance between donation and potential recipients. An early and accurate prognostic system based on the integration of laboratory indicators, clinical events and some mathematic logistic equations is needed to optimize treatment for patients. As parts of the scoring systems, the MELD was the most common and the donor-MELD was the most innovative for patients on the waiting list for liver transplantation. This review aims to highlight the various features and prognostic capabilities of these scoring systems.

Immunosuppression in acutely decompensated cirrhosis is mediated by prostaglandin E2

Liver disease is one of the leading causes of death worldwide. Patients with cirrhosis display an increased predisposition to and mortality from infection due to multimodal defects in the innate immune system; however, the causative mechanism has remained elusive. We present evidence that the cyclooxygenase (COX)-derived eicosanoid prostaglandin E2 (PGE2) drives cirrhosis-associated immunosuppression. We observed elevated circulating concentrations (more than seven times as high as in healthy volunteers) of PGE2 in patients with acute decompensation of cirrhosis. Plasma from these and patients with end-stage liver disease (ESLD) suppressed macrophage proinflammatory cytokine secretion and bacterial killing in vitro in a PGE2-dependent manner via the prostanoid type E receptor-2 (EP2), effects not seen with plasma from patients with stable cirrhosis (Child-Pugh score grade A). Albumin, which reduces PGE2 bioavailability, was decreased in the serum of patients with acute decompensation or ESLD (<30 mg/dl) and appears to have a role in modulating PGE2-mediated immune dysfunction. In vivo administration of human albumin solution to these patients significantly improved the plasma-induced impairment of macrophage proinflammatory cytokine production in vitro. Two mouse models of liver injury (bile duct ligation and carbon tetrachloride) also exhibited elevated PGE2, reduced circulating albumin concentrations and EP2-mediated immunosuppression. Treatment with COX inhibitors or albumin restored immune competence and survival following infection with group B Streptococcus. Taken together, human albumin solution infusions may be used to reduce circulating PGE2 levels, attenuating immune suppression and reducing the risk of infection in patients with acutely decompensated cirrhosis or ESLD.