Outcomes in Adults With Acute Liver Failure Between 1998 and 2013: An Observational Cohort Study

Acute liver failure in patients admitted to the intensive care unit-a Viennese retrospective single-center analysis

BACKGROUND

Acute liver failure (ALF) is characterized by a rapid deterioration of liver function and a high mortality without transplantation depending on etiology and onset. Immediate transfer to a dedicated intensive care unit (ICU) and evaluation for high-urgency liver transplantation (HU-LTx) is recommended to maximize chances of survival. Data on ALF epidemiology are limited, particularly for Central Europe.

METHODS

This retrospective single-center study included all ALF patients admitted to the ICU of the Department of Gastroenterology and Hepatology at the Vienna General Hospital between 2012 and 2024.

RESULTS

Overall, 31 patients (median age of 44 [interquartile range, IQR 32-56] years, 20 [65%] female) were included. The primary causes of ALF were viral infections (n = 8; 26%), autoimmune hepatitis (n = 5; 16%), drug-induced liver injury (DILI; n = 3; 10%), and Wilson's disease (n = 4; 13%), while in 8 patients (26%) no cause was identified. Median length of ICU stay was 12 (IQR 4-21) days, with mean sequential organ failure assessment (SOFA) and simplified acute physiology score II (SAPS II) scores of 10.55 ± 4.56 and 40.97 ± 14.84. Overall ICU survival was 61% (n = 19). Non-HU-LTx patients (n = 18) had an ICU survival of 44%. HU-LTx was performed in 13 patients (42%), with 12 patients (92%) surviving 28 days. The 6‑month overall survival of HU-LTx patients was 85%.

CONCLUSION

The diverse causes of ALF in Central Europe include most commonly viral infections, autoimmune hepatitis, and DILI. HU-LTx was required and performed in almost half of patients and was associated with favorable survival rates, underscoring the importance of ICU management and early transfer to liver transplantation centers in the management of ALF.

Mechanisms of drug induced liver injury

Drug induced liver injury (DILI) is a serious and potentially life-threatening condition resulting from an adverse drug reaction. Both the clinical manifestations and pathological mechanisms of DILI vary depending on drug characteristics, dose, duration of exposure as well as host specific factors. Disease onset can occur within days or months after the introduction of a drug. This has challenged identification of disease specific biomarkers and resulted in delayed and even erroneous diagnosis of patients. Apart from discontinuation of current pharmacotherapy, options for DILI patients are scarce and the condition can sometimes continue or worsen after drugs are discontinued or result in irreversible liver damage such as cirrhosis. This illustrates the need to uncover relevant pathological pathways that will pave the road for targeted interventions. In an effort to accommodate these needs, novel insights from preclinical and cellular disease modeling have allowed coupling of specific drugs to potential mechanisms of toxicity. This review outlines three signaling pathways of DILI: organelle stress, cholestasis, and immune responses, discusses their interplay with oxidative stress, and provides examples of drugs specifically targeting one or more steps in these pathways. A systematic approach identifying specific mechanisms of DILI could allow for the assembly of large databases, in turn enabling advanced computational modelling to provide accurate predictions of the DILI potential of both known drugs and future drug candidates.

A non-inferiority randomised controlled trial of a Shorter Acetylcysteine Regimen for Paracetamol Overdose - the SARPO trial

BACKGROUND

Paracetamol is a common overdose worldwide. Early acetylcysteine treatment can prevent hepatotoxicity. Multiple intravenous acetylcysteine regimens exist; the commonest recommending 300mg/kg over 20h. We investigated the effectiveness and safety of a shorter regimen in paracetamol overdoses ≤30g.

METHODS

In a multicentre non-inferiority randomised controlled trial, 204 patients from three hospitals with acute paracetamol overdose ≤ 30g presenting within 8h, were randomised to standard 20h acetylcysteine (200mg/kg/4h, 100mg/kg/16h) regimen or short 12h acetylcysteine (200mg/kg/4h, 50mg/kg/8h) regimen. The primary outcome was the absolute difference between alanine transaminase (ALT) 24h post-ingestion and admission ALT (ΔALT24). Secondary outcomes included ALT>150U/L at 24h and double admission ALT, systemic hypersensitivity and gastrointestinal adverse effects.

RESULTS

The two groups were similar in age, gender, dose ingested, paracetamol concentration, baseline ALT, hospital, charcoal administration and time until acetylcysteine. The shorter regimen was non-inferior to the standard regimen. ΔALT24 for 107 patients given the shorter regimen was median -2U/L (Interquartile range [IQR]:-7 to 1U/L) compared to 97 given the standard regimen, median -1U/L (IQR:-5 to 1.5U/L); difference in medians of -1U/L; 95% confidence interval:-3 to 1U/L; less than the upper non-inferiority margin of 5). No patient receiving the shorter regimen had a 24h ALT double admission and >150U/L, compared to one receiving the standard regimen. No patient had an ALT>1000U/L. Systemic hypersensitivity reactions were similar between groups [9/107 (8%) for short versus 10/97 (10%) standard regimen]. Gastrointestinal adverse effects occurred in 78/107 patients (73%) receiving the short versus 63/97 (65%) receiving the standard regimen.

CONCLUSIONS

The shorter 12h acetylcysteine regimen had the same effectiveness and safety as the standard 20h regimen in acute paracetamol overdoses ≤30g, almost halving the length of treatment required.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry number ACTRN12616001617459.

Assessing Liver Function in Rat Models of Acute Liver Failure Using Single-Photon Emission Computed Tomography and Cytokine Levels

OBJECTIVE

To evaluate liver function using dynamic hepatobiliary single-photon emission computed tomography (SPECT) in different rat models of acute liver failure.

METHODS

Twenty-four 6-8-week-old male Sprague-Dawley rats (weight 190-200 g) were evenly divided into four groups. Acute liver failure was induced by intraperitoneal injection of D-galactosamine (D-GalN, 600 mg/kg) and lipopolysaccharide (LPS, 10 µg/kg), common bile duct ligation surgery, and removing 70% of the liver mass. The fourth group served as the control without intervention. The time-activity curves for the liver and heart were generated from dynamic SPECT scans with 99mTc-ethylene hepatobiliary iminodiacetic acid (EHIDA). Image-derived functional parameters (5-minute heart/liver index [HLI5] and 15-minute receptor index [LHL15]) were calculated. Furthermore, correlations of image-derived parameters with serum interleukin-6 (IL-6) levels, liver aspartate aminotransferase (AST) and alanine transaminase (ALT) levels, and liver mRNA expression levels of tumor necrosis factor-α (TNF-α) and chemokine ligand-10 (CXCL-10) were analyzed.

RESULTS

All animals in the experimental groups exhibited varying degrees of liver damage. The SPECT images and indexes (HLI5 and LHL15) of the experimental groups significantly differed from those of the control group (P < 0.05). In the experimental groups, serum IL-6 levels and liver mRNA levels of TNF-α and CXCL-10 were significantly higher, while liver AST and ALT levels were significantly lower than those in the control group (P < 0.05).

CONCLUSION

Using SPECT with 99mTc-EHIDA, along with the calculated indexes and levels of various cytokines, presents a dependable method for assessing liver function.

Integrated cascade antioxidant nanozymes-Cu5.4O@CNDs combat acute liver injury by regulating retinol metabolism

Background: Acute liver failure (ALF) represents a critical medical condition marked by the abrupt onset of hepatocyte damage, commonly induced by etiological factors such as hepatic ischemia/reperfusion injury (HIRI) and drug-induced hepatotoxicity. Across various types of liver injury, oxidative stress, heightened inflammatory responses, and dysregulated hepatic retinol metabolism are pivotal contributors, particularly in the context of excessive reactive oxygen species (ROS). Methods: C-dots were combined with Cu5.4O USNPs to synthesize a cost-effective nanozyme, Cu5.4O@CNDs, which mimics the activity of cascade enzymes. The in vitro evaluation demonstrated the ROS scavenging and anti-inflammatory capacity of Cu5.4O@CNDs. The therapeutic potential of Cu5.4O@CNDs was evaluated in vivo using mouse models of hepatic ischemia/reperfusion injury and LPS/D-GalN induced hepatitis, with transcriptome analysis conducted to clarify the mechanism underlying hepatoprotection. Results: The Cu5.4O@CNDs demonstrated superoxide dismutase (SOD) and catalase (CAT) enzyme activities, as well as hydroxyl radical (·OH) scavenging capabilities, effectively mitigating ROS in vitro. Furthermore, the Cu5.4O@CNDs exhibited remarkable targeting efficacy towards inflammation cells induced by H2O2 and hepatic tissues in murine models of hepatitis, alongside exhibiting favorable biocompatibility in both in vitro and in vivo settings. Moreover, it has been demonstrated that Cu5.4O@CNDs effectively scavenged ROS, thereby enhancing cell survival in vitro. Additionally, Cu5.4O@CNDs exhibited significant therapeutic efficacy in mice models of HIRI and lipopolysaccharide-induced acute lung injury (LPS-ALI). This efficacy was achieved through the modulation of the ROS response and hepatic inflammatory network, as well as the amelioration of disruptions in hepatic retinol metabolism. Conclusions: In summary, this study demonstrates that Cu5.4O@CNDs exhibit significant potential for the treatment of various acute liver injury conditions, suggesting their promise as an intervention strategy for clinical application.

DIA-based quantitative proteomics explores the mechanism of amelioration of APAP-induced liver injury by anoectochilus roxburghii (Wall.) Lindl

Background

Drug-induced liver injury (DILI) is the most common cause of acute liver injury. Anoectochilus roxburghii (Wall.) Lindl. (AR) and its polysaccharide fractions (ARPs) have been shown to have effective therapeutic effects with minimal side effects on a wide range of diseases including hepatopathy. This study aims to determine the therapeutic effects of ARPs on acetaminophen (APAP)-induced liver injury and to explore the mechanistic pathways involved.

Methods

C57BL/6J male mice at 8 weeks were used to construct a model of APAP-induced liver injury. The acute hepatic injury was induced by oral administration of APAP (300 mg/kg) before 16 h fasting. For therapeutic experiment, mice were gavaged with the water extract of AR (AR.WE) or the purified ARPs before and after APAP administration. Biochemical analyses, ELISA analyses, H&E staining, RT-PCR, and Quantitative proteomic analysis were used to investigate the effects and mechanisms of AR on DILI.

Results

Both AR.WE. and the purified ARPs treatment reduced APAP-induced liver injury, decreased hepatic glutathione and TNF-α levels, alleviated oxidative stress and inflammation. Quantitative proteomic analysis revealed that ARPs downregulated the protein levels involved in apoptosis, inflammation, oxidative stress, necroptosis, while upregulated the protein levels involved in autophagy. These protective effects of ARPs are possibly related to the downregulation of vATPase activity and thus participating in the autophagic process and ferroptosis.

Conclusion

ARPs can protect mice against APAP-induced liver injury, alleviate oxidative stress and inflammation. Our study reveals a potential therapeutic effect for ARPs in protecting APAP-induced liver injury.

Hepatocyte cellular repressor of E1A-stimulated genes 1 protects against acetaminophen-induced liver injury by promoting autophagy

Acetaminophen-induced liver injury (AILI) accounts for a significant proportion of acute liver failure emphasizing the critical need to elucidate AILI pathogenesis and to identify effective therapeutic agents. Cellular repressor of E1A-stimulated genes 1 (CREG1) is a secreted glycoprotein that plays a crucial role in maintaining liver homeostasis. Prior studies have shown that CREG1 mitigates liver injury, steatosis, and inflammation associated with multiple liver diseases. In this study we investigated the role and therapeutic potential of CREG1 in AILI. We showed that the expression levels of CREG1 were markedly elevated in livers of AILI mice and patients with drug-induced liver injury (DILI), which was also observed in primary hepatocytes treated with acetaminophen (APAP). Hepatocyte-specific CREG1 deficiency mice were more sensitive to APAP compared to Creg1fl/fl mice, whereas AAV8-mediated CREG1 overexpression protected mice from AILI. We demonstrated that CREG1 deficiency impaired autophagy and activated inflammatory signaling pathways. Pre-administration of A769662 to activate AMPK or rapamycin to induce autophagy prevented the liver injury in Creg1Δhep mice. Coherently, the protective effect of CREG1 overexpression against AILI could be inhibited by dorsomorphin, an AMPK inhibitor. These findings suggest that CREG1 alleviates AILI by regulating autophagy through AMPK activation, and CREG1 represents a promising therapeutics target for AILI treatment.

Semaphorin 7a is protective through immune modulation during acetaminophen-induced liver injury

BACKGROUND AND AIM

Acetaminophen (APAP) induced acute liver injury (ALI), the leading cause acute liver failure in the western world, has limited treatment options. APAP toxicity results in massive hepatic necrosis and secondary infiltrating monocytes and neutrophils, which contribute to pathogenesis. Semaphorin 7a (Sema7a), a chemoattractant and modulator of monocytes and neutrophils, is a potential therapeutic target in other conditions, but its role in APAP-ALI is unexplored.

METHODS

Wild-type (WT) and Sema7a knockout (KO) mice were examined during APAP-ALI. Serum liver function tests, histological analysis and cellular localisation of Sema7a and its receptors, Plexin C1 and Integrin β1, were examined. Serum cytokines were quantified, tissue macrophages and neutrophils were localised, and in vivo phenotype, including phagocytosis, was assessed by immunohistochemistry and flow cytometry.

RESULTS

Sema7a was expressed by HNF4α + peri-necrotic hepatocytes circumferentially during APAP-ALI injury phases, and serum concentrations were increased, and correlated with hepatic injury. Sema7a KO mice had increased circulating inflammatory cytokines and significantly less hepatic F4/80 + macrophages, a cell type required for hepatic repair. Sema7a KO mice had higher necrotic area neutrophils, and increased neutrophil chemoattractant CXCL1. Without Sema7a expression, mice displayed increased necrosis and liver injury markers compared to Sema7a WT mice. Without peri-necrotic hepatocyte Sema7a expression, we also identified increased cell death and hepatic cellular stress outside of necrosis.

CONCLUSION

We have identified a novel protective role of Sema7a during injury phases of APAP-ALI. Without peri-necrotic hepatocyte Sema7a expression and secretion, there is increased inflammation, time specific worsened hepatic necrosis and increased hepatic cell stress and death outside of the necrotic zone.

Association of Acetaminophen (Paracetamol) Use With Severity and Outcomes in Patients With Viral Hepatitis-Associated Acute Liver Failure

INTRODUCTION

Acute viral hepatitis (AVH) comprises 11% of acute liver failure (ALF) in North America while acetaminophen (APAP) toxicity represents 46%. The use of APAP to treat prodromal hepatitis symptoms is common. It is unknown if concurrent APAP use impacts liver injury in AVH-induced ALF.

METHODS

In this prospective, multicenter cohort study, 356 patients meeting criteria for AVH including hepatitis A, B, Epstein-Barr virus, and herpes simplex virus, all leading to ALF (hepatic encephalopathy after acute illness, international normalized ratio ≥1.5), or acute liver injury (acute liver injury, international normalized ratio >2.0, no hepatic encephalopathy) were reviewed for evidence of APAP use: APAP ingestion history or measurement of serum APAP level or APAP-CYS adducts, a specific biomarker released into blood with APAP injury. Patients were grouped by APAP exposure level, from high (measurable APAP levels or toxic APAP-CYS), medium (therapeutic APAP-CYS), low (history of APAP ingestion only and/or barely detectable APAP-CYS), or no exposure recorded.

RESULTS

Two hundred five of 356 patients (57.5%) with AVH-ALF had evidence of APAP use: 87 out of 356 (24%) demonstrated high or medium exposures. The aminotransferase and bilirubin levels of high/medium group resembled a mixed APAP-viral injury. Mortality was the highest (51.6%, 21.4%, 28.8%, and 30.5%), and transplant-free survival was the lowest (22.6%, 44.6%, 41.5%, and 40.4%) in the high exposure group compared with medium, low, and no exposure groups. However, the specific comparisons of mortality and transplant-free survival between the high exposure and no exposure groups were not statistically different even after adjusting for baseline patient characteristics differences.

DISCUSSION

APAP use in AVH-ALF is common and may negatively impact outcomes compared with little or no APAP exposure. Prospective studies of the safest and effective dose of APAP to use in patients with AVH are needed.

Extracorporeal liver support and liver transplantation for acute-on-chronic liver failure

Acute-on-chronic liver failure (ACLF) is defined by acute decompensation, organ failure and a high risk of short-term mortality. This condition is characterized by an overwhelming systemic inflammatory response. Despite treating the precipitating event, intensive monitoring and organ support, clinical deterioration can occur with very poor outcomes. During the last decades, several extracorporeal liver support systems have been developed to try to reduce ongoing liver injury and provide an improved environment for the liver to regenerate or as a bridging therapy until liver transplantation. Several clinical trials have been performed to evaluate the clinical efficacy of extracorporeal liver support systems, but no clear impact on survival has been proven. DIALIVE is a novel extracorporeal liver support device that has been built to specifically address the pathophysiological derangements responsible for the development of ACLF by replacing dysfunctional albumin and removing pathogen and damage-associated molecular patterns (PAMPs and DAMPs). In phase II clinical trial, DIALIVE appears to be safe, and it seems to be associated with a faster time to the resolution of ACLF compared with standard medical treatment. Even in patients with severe ACLF, liver transplantation saves lives and there is clear evidence of transplant benefit. Careful selection of patients is required to attain good results from liver transplantation, but many questions remain unanswered. In this review, we describe the current perspectives on the use of extracorporeal liver support and liver transplantation for ACLF patients.

Artificial Intelligence: An Emerging Tool for Studying Drug-Induced Liver Injury

Drug-induced liver injury (DILI) is a complex and potentially severe adverse reaction to drugs, herbal products or dietary supplements. DILI can mimic other liver diseases clinical presentation, and currently lacks specific diagnostic biomarkers, which hinders its diagnosis. In some cases, DILI may progress to acute liver failure. Given its public health risk, novel methodologies to enhance the understanding of DILI are crucial. Recently, the increasing availability of larger datasets has highlighted artificial intelligence (AI) as a powerful tool to construct complex models. In this review, we summarise the evidence about the use of AI in DILI research, explaining fundamental AI concepts and its subfields. We present findings from AI-based approaches in DILI investigations for risk stratification, prognostic evaluation and causality assessment and discuss the adoption of natural language processing (NLP) and large language models (LLM) in the clinical setting. Finally, we explore future perspectives and challenges in utilising AI for DILI research.

A novel KEAP1 inhibitor, tiliroside, activates NRF2 to protect against acetaminophen-induced oxidative stress and acute liver injury

BACKGROUND

Acetaminophen-induced acute liver injury (AILI) is one of the common causes of abrupt liver failure in numerous nations. Several previous studies revealed that tiliroside, a glycoside flavonoid, exerts neuroprotective and renal protective effects. However, whether it has hepatoprotective effects is not known. The objective of this research is to examine whether tiliroside can protect against AILI.

METHODS

AILI mouse and cell models were performed to evaluate the protective effects of tiliroside. Molecular docking, cellular thermal shift assay, immunoprecipitation, and RNA-seq were performed to analyze the possible mechanisms of tiliroside.

RESULTS

In vivo, tiliroside attenuated AILI in mice significantly, as evidenced by lower ALT and AST levels. Molecular docking, cellular thermal shift assay, and RNA-seq analysis revealed that tiliroside promoted the activation of nuclear factor erythroid 2-related factor 2 (NRF2) and the expression of its downstream genes through disruption of the NRF2-KEAP1 protein-protein interaction to inhibit KEAP1-mediated ubiquitination and degradation of NRF2, thereby inhibiting oxidative stress in the livers of AILI mice. Furthermore, hepatocyte-specific knockout of NRF2 greatly attenuated the hepatic-protective effects of tiliroside in mice. In vitro, tiliroside protected against acetaminophen-induced oxidative stress on cultured hepatocytes through activation of NRF2. In addition, NRF2 knockout markedly blunted the protection effects of tiliroside, suggesting that NRF2 mediates the hepatic-protective effects of tiliroside.

CONCLUSIONS

Our study demonstrated that tiliroside could protect against AILI by activating the KEAP1/NRF2 pathway, which primarily inhibits the processing of oxidative stress and cell death. Our results suggest that tiliroside could serve as a potential agent for the clinical treatment of AILI.

Potential Biomarkers and Therapeutic Targets in Hepatitis B Virus-related Acute Liver Failure: Interplay of the Ferroptosis, Autophagy and Immune Responses

Hepatitis B virus-related acute liver failure (HBV-ALF) is characterized by a high fatality rate, its pathogenesis remains unclear and the therapeutic efficacy is limited. Ferroptosis which closely related to autophagy may be an underlying mechanism of HBV-ALF. The aim of this study was to identify key ferroptosis- and autophagy-related genes and pathways and provide insight into potential therapeutic approaches for HBV-ALF. We accessed the GSE14668 and GSE96851 datasets from the Gene Expression Omnibus (GEO) database and focused on differentially expressed genes (DEGs), ferroptosis-related DEGs (FRGs) and autophagy-related DEGs (ARGs). Hub genes were subsequently analyzed for enrichment, protein‒protein interactions (PPIs), and different immunological microenvironments, and potential hub gene were identified using MCC method and LASSO. Gene-targeted drugs were from the DGIdb and DrugBank databases.A total of 1462 DEGs were identified (726 upregulated and 736 downregulated). Enriched pathways included amino acid metabolism and immune and inflammatory responses, potentially serving as biomarkers for ALF pathogenesis. After integration with the FerrDb and HADb databases, 55 FRGs and 45 ARGs were identified. Thirteen hub genes (SLC7A11, HMOX1, G6PD, RRM2, KIF20A, HELLS, GPT2, GLS2, SPP1, CCR2, DCN, IRS1, and IGF1) were identified which closely associated with the immune microenvironment. Interplay among these genes occurred primarily through HMOX1. Moreover, we identified several hub gene-targeted drugs that may be effective in HBV-ALF treatment, such as riluzole, acetylcysteine, NADH and Vitamin E.Thirteen hub genes may play crucial roles in HBV-ALF progression, particularly, the HMOX1. Furthermore, drug target exploration offered promising avenues for therapeutic intervention in patients with HBV-ALF.

Paracetamol did not improve the analgesic efficacy with regional block after video assisted thoracoscopic surgery: a randomized controlled trial

BACKGROUND

Various analgesic techniques have been applied, the pain after video assisted thoracic surgery (VATS) is still challenging for anesthesiologists. Paracetamol provide analgesic efficacy in many surgeries. However, clinical evidence in the lung surgery with regional block remain limited. This monocentric double-blind randomized controlled trial investigates the efficacy of paracetamol after VATS with regional block.

METHODS

A total of 90 patients were randomized to receive paracetamol (1 g) or normal saline. Erector Spinae Plane Block and Intercostal Nerve block were applied during the surgery. The Visual Analogue Scales (VAS) pain score was measured in the PACU as well as 6, 12, 24, and 48 h postoperatively. And the total dose of rescue analgesics administered to patients in morphine milligram equivalents (MME), satisfaction score, length of hospital stays, and incidence of nausea and vomiting were also recorded.

RESULTS

The VAS pain score at each time point, the primary endpoint, did not differ between the groups (3.09 ± 2.14 vs. 2.53 ± 1.67, p = 0.174 at PACU; 4.56 ± 2.80 vs. 4.06 ± 2.46, p = 0.368 at 6 h; 3.07 ± 1.98 vs. 3.44 ± 2.48, p = 0.427 at 12 h; 2.10 ± 2.00 vs. 2.49 ± 2.07, p = 0.368 at 24 h; and 1.93 ± 1.76 vs. 2.39 ± 1.97, p = 0.251 at 48 h postoperatively). Satisfaction scores (4.37 ± 0.76 vs. 4.14 ± 0.88, p = 0.201), nausea (35.6% vs. 37.8%, p = 0.827), hypotension (2.2% vs. 0.0%, p = 0.317), and bradycardia (6.7% vs. 2.2%, p = 0.309) were also reported at similar rates.

CONCLUSIONS

The analgesic efficacy of one gram of paracetamol with ESPB and ICNB after VATS was not proven. Thus, caution should be exercised when prescribing paracetamol for pain control during VATS.

TRIAL REGISTRATION

this trial was registered on Clinical Research Information Service (CRIS), Republic of Korea (KCT0008710). Registration date: 17/08/2023.

Liver Xenotransplantation: A Path to Clinical Reality

Liver xenotransplantation has emerged as a potential solution to the shortage of deceased human donor organs and is now becoming a reality due to recent developments in genetic engineering and immunosuppressive therapy. Early efforts using non-human primates and genetically modified pigs faced significant challenges such as thrombocytopenia and graft rejection. Understanding the mechanism behind those challenges and using novel genetically engineered pigs enabled researchers to overcome some of the hurdles, but more research is needed. However, new advances might allow pig liver xenotransplantation to potentially serve as a bridge to liver allotransplantation or allow native liver regeneration in the near future.

The emerging role of alternatively activated macrophages to treat acute liver injury

Acute liver injury (ALI) has a clear requirement for novel therapies. One emerging option is the use of alternatively activated macrophages (AAMs); a distinct subtype of macrophage with a role in liver injury control and repair. In this comprehensive review, we provide an overview of the current limited options for ALI, and the potential advantages offered by AAMs. We describe the evidence supporting their use from in vitro studies, pre-clinical animal studies, and human clinical trials. We suggest why the first evidence for the clinical use of AAMs is likely to be found in acetaminophen toxicity, and discuss the specific evidence for AAM use in this population, as well as potential applications for AAMs in other patient populations. The key domains by which the performance of AAMs for the treatment of ALI will be assessed are identified, and remaining challenges to the successful delivery of AAMs to clinic are explored.

Liver transplantation in acute liver failure

ABO-compatible Orthotopic Liver Transplantation (OLT) is the standard treatment for patients with acute liver failure (ALF) who meet the criteria for poor prognosis. Contraindications to liver transplantation may be related to the presence of severe medical or psychiatric comorbidities, or to an unstable clinical state incompatible with transplantation. Early mortality predictive scores and factors have been developed to identify futile transplantations that exacerbate organ shortage. However, these scores are not sufficiently reliable to contraindicate transplantation. Auxiliary liver transplantation, two-stage transplantation (total hepatectomy with portal-caval anastomosis followed by delayed orthotopic liver transplantation), ABO-incompatible liver transplantation, living-donor transplantation, and living-auxiliary liver donor transplantation are alternatives to OLT. The selection of appropriate techniques must fulfill specific criteria. ABO-incompatible transplantation remains an exception, even though immunosuppressive strategies have improved prognosis. The overall survival and graft survival rates at 1 and 5 years after liver transplantation for ALF are 79 % and 72 % in Europe, and 84 % and 73 % in the United States, respectively. The survival rate has significantly improved in recent years.

The role of exosomal lncRNAs in acetaminophen-induced induced liver injury in SD rats

Background

Drug-induced liver injury (DILI) is a leading cause of drug development failures during clinical trials and post-market introduction. Current biomarkers, such as ALT and AST, lack the necessary specificity and sensitivity needed for accurate detection. Exosomes, which protect LncRNAs from RNase degradation, could provide reliable and easily accessible options for biomarkers.

Materials and methods

RNA-sequencing was used to identify differentially expressed LncRNAs (DE-LncRNAs), followed by isolation of LncRNAs from plasma exosomes in this study. Exosome characterization was conducted by transmission electron microscopy (TEM), nanoparticle tracking analysis (NTA), and Western blot (WB). Bioinformatics analysis included functional enrichment and co-expression network analysis. Five rat models were established, and quantitative real-time PCR was used to verify the specificity and sensitivity of two candidate exosomal LncRNAs.

Results

The APAP-induced hepatocellular injury model was successfully established for RNA-sequencing, leading to the identification of several differentially expressed exosomal LncRNAs. Eight upregulated exosomal DE-LncRNAs were selected for validation. Among them, NONRATT018001.2 (p < 0.05) and MSTRG.73954.4 (p < 0.05) exhibited a more than 2-fold increase in expression levels. In hepatocellular injury and intrahepatic cholestasis models, both NONRATT018001.2 and MSTRG.73954.4 showed earlier increases compared to serum biomarkers ALT and AST. However, no histological changes were observed until the final time point. In the fatty liver model, NONRATT018001.2 and MSTRG.73954.4 increased earlier than ALT and AST at 21 days. By the 7th day, minor steatosis was evident in liver tissue, while the expression levels of the two candidate exosomal LncRNAs exceeded 2 and 4 times, respectively. In the hepatic fibrosis model, NONRATT018001.2 and MSTRG.73954.4 showed increases at every time point. By the 49th day, hepatocellular necrosis and fibrosis were observed in the liver tissue, with NONRATT018001.2 showing an increase of more than 8 times. The specificity of the identified exosomal DE-LncRNAs was verified using a myocardial injury model and they showed no significant differences between the case and control groups.

Conclusion

NONRATT018001.2 and MSTRG.73954.4 hold potential as biomarkers for distinguishing different types of organ injury induced by drugs, particularly enabling early prediction of liver injury. Further experiments, such as siRNA interference or gene knockout, are warranted to explore the underlying mechanisms of these LncRNAs.

Establishing a predictive nomogram for 21‑day transplant-free survival in drug-induced liver failure

BACKGROUND

The high prevalence of drug-induced liver failure (DILF) have drawn great attention from clinicians.

AIM

To further delineate the clinical features of DILF and develop an easily applicable nomogram, based on readily-discernable clinical data, to predict transplant-free survival (TFS) at different time points.

METHODS

202 DILF patients were enrolled between January 2016 and December 2022, and were followed up from DILF diagnosis to death, liver transplantation, or 91 days afterward, whichever came first. The primary endpoint, though, was 21-day TFS. Clinical data was collected from all patients, and independent risk factors associated with death/liver transplantation was identified using both uni- and multi-variate Cox regression analyses.

RESULTS

Independent risk factors incorporated into the predictive nomogram are neutrophils (HR = 1.148, 95% CI = 1.048-1.257), prothrombin time (HR = 1.048, 95% CI = 1.017-1.080), albumin (HR = 0.880, 95% CI = 0.823-0.941), acute kidney injury (HR = 2.487, 95% CI = 1.134-5.452), and hepatic encephalopathy (HR = 3.378, 95% CI = 1.744-6.543). The resulting nomogram was highly predictive, with an area under the curve of 0.947 for 21-day TFS.

CONCLUSIONS

Compared to existing models, such as the Model for End-Stage Liver Disease score, the predictive nomogram is more accurate, only requires easily-measurable clinical and laboratory metrics, as well as being able to directly calculate TFS at various time points.

Advanced strategies for intensive care management of acute liver failure

Acute liver failure (ALF) is defined as the loss of hepatic function in conjunction with hepatic encephalopathy and coagulopathy. There is histological evidence of profound hepatocyte damage. If it is not aggressively managed, ALF can be fatal within a few days. It is a rare disease, often occurring in patients without prior liver disease. Despite numerous causes, ALF usually presents as acute liver necrosis with a clinical picture that includes cognitive dysfunction, increased aminotransferases, and severe coagulopathy. It is essential to distinguish between ALF and acute-on-chronic liver failure (ACLF). Causes for ALF include paracetamol Acute liver failure (ALF) is characterized by acute liver dysfunction associated with overdose, right heart failure (ischemic liver injury), viral hepatitis (A, B, D and E), autoimmune hepatitis and drug-induced liver injury (including some herbal and nutritional supplements). In developed countries, the prevalence of ALF is 1:1,000,000. Survival rates have increased due to improved ICU management.

Liver assistive devices in acute liver failure: Current use and future directions

Acute liver failure (ALF) is a rare syndrome where rapid deterioration of liver function occurs after an acute insult in a patient without prior chronic liver disease and leads to jaundice, hepatic encephalopathy (HE), and oftentimes multiorgan failure (MOF). At this time, the only definitive treatment for ALF is LT but some patients, particularly APAP-induced ALF patients, may have ongoing regenerative capacity of the liver and may not require LT with ongoing supportive management. As a result, extracorporeal liver support (ECLS) has been a topic of interest both as a bridge to LT and as a bridge to spontaneous recovery and aims to remove damaging toxins that further aggravate liver failure, stimulate regeneration of the liver, and improve pathophysiologic consequences of liver failure. There are currently two categories of ECLS (artificial and bioartificial). Artificial ECLS does not incorporate active hepatocytes and are based on the principles of filtration and adsorption and includes renal replacement therapy (RRT), plasma adsorption including plasma exchange and Prometheus (Fractionated Plasma Separation and Adsorption), and albumin dialysis including MARS (Molecular Adsorbent Recirculating System) and SPAD (Single Pass Albumin Dialysis). Bioartificial ECLS incorporates active hepatocytes (human or porcine in origin) to improve liver detoxification capacity and to support hepatic synthetic function and includes ELAD (Extracorporeal Liver Assist Device) and HepatAssist.

Liver transplantation for Wilson disease: Current knowledge and future perspectives

Liver transplantation currently represents a therapeutic option for patients with Wilson disease presenting with end-stage liver disease or acute liver failure. Indeed, it has been associated with excellent postoperative survival curves in view of young age at transplant and absence of recurrence. Attention has shifted over the past decades to a wise expansion of indications for liver transplantation. Evidence has emerged supporting the transplantation of carefully selected patients with primarily neuropsychiatric symptoms and compensated cirrhosis. The rationale behind this approach is the potential for surgery to improve copper homeostasis and consequently ameliorate neuropsychiatric symptoms. However, several questions remain unanswered, such as how to establish thresholds for assessing pretransplant neuropsychiatric impairment, how to standardize preoperative neurological assessments, and how to define postoperative outcomes for patients meeting these specific criteria. Furthermore, a disease-specific approach will be proposed both for the liver transplant evaluation of candidates with Wilson disease and for patient care during the transplant waiting period, highlighting the peculiarities of this systemic disease.

Severely Hyperammonemic Acute Liver Failure due to Paracetamol Overdose: The Impact of High-Intensity Continuous Renal Replacement Therapy

INTRODUCTION

Paracetamol (acetaminophen)-induced acute liver failure (ALF) with severe hyperammonemia (ammonia >100 µmol⋅L-1) is a life-threatening condition. A strategy based on high-intensity continuous renal replacement therapy (CRRT) without early (up to day seven) transplantation may enable clinicians to safely identify which patients can recover and survive and which patients require transplantation.

METHODS

We conducted a single-center, retrospective cohort study of patients with severely hyperammonemic paracetamol-induced ALF. The primary outcome was early transplant-free survival.

RESULTS

We studied 84 patients (median age: 38; female sex: 79 [85%]) over a 12-year period (median ammonia level at ICU admission: 153 µmol⋅L-1; median peak aspartate aminotransferase (AST): 10,029 U⋅L-1; median lactate: 5.0 mmol⋅L-1; and median INR: 4.4) and 55 (65%) with King's College criteria for transplantation. Overall, 87% received high-intensity CRRT (92% in 2020-2023). Median CRRT intensity was 54 mL⋅kg-1⋅hr-1 within the first 48 h and increased by 1.8 mL⋅kg-1⋅hr-1 per year during the study period (p = 0.002). Transplant-free survival to day 7 was 86% in 2011-2023 and 96% in 2020-2023. Overall, only 4 patients were transplanted and only 1 (4%) in 2020-2023. On multivariable Cox analysis, factors independently associated with failure to achieve day seven transplant-free survival were higher APACHE III score (HR = 1.05, 95% CI: 1.02-1.08), higher lactate (HR = 1.27, 95% CI: 1.12-1.44), and lower platelet count at ICU admission (HR = 0.85, 95% CI: 0.78-0.93) and the median effluent dose applied within the first 48 h of ICU admission (HR = 0.67, 95% CI: 0.46-0.98).

CONCLUSIONS

Early transplant-free survival is achievable in most patients with paracetamol-induced ALF and severe hyperammonemia with a treatment based on high-intensity CRRT. Such transplant-free survival increased over time together with increased CRRT dose.

Outcomes of patients with acute liver failure not listed for liver transplantation: A cohort analysis

BACKGROUND

Acute liver failure (ALF) is a rare condition leading to morbidity and mortality. Liver transplantation (LT) is often required, but patients are not always listed for LT. There is a lack of data regarding outcomes in these patients. Our aim is to describe outcomes of patients with ALF not listed for LT and to compare this with those listed for LT.

METHODS

Retrospective analysis of all nonlisted patients with ALF enrolled in the Acute Liver Failure Study Group (ALFSG) registry between 1998 and 2018. The primary outcome was 21-day mortality. Multivariable logistic regression was done to identify factors associated with 21-day mortality. The comparison was then made with patients with ALF listed for LT.

RESULTS

A total of 1672 patients with ALF were not listed for LT. The median age was 41 (IQR: 30-54). Three hundred seventy-one (28.9%) patients were too sick to list. The most common etiology was acetaminophen toxicity (54.8%). Five hundred fifty-eight (35.7%) patients died at 21 days. After adjusting for relevant covariates, King's College Criteria (adjusted odds ratio: 3.17, CI 2.23-4.51), mechanical ventilation (adjusted odds ratio: 1.53, CI: 1.01-2.33), and vasopressors (adjusted odds ratio: 2.10, CI: 1.43-3.08) (p < 0.05 for all) were independently associated with 21-day mortality. Compared to listed patients, nonlisted patients had higher mortality (35.7% vs. 24.3%). Patients deemed not sick enough had greater than 95% survival, while those deemed too sick still had >30% survival.

CONCLUSIONS

Despite no LT, the majority of patients were alive at 21 days. Survival was lower in nonlisted patients. Clinicians are more accurate in deeming patients not sick enough to require LT as opposed to deeming patients too sick to survive.

Liver transplantation for acute liver failure and acute-on-chronic liver failure

Acute liver failure (ALF) and acute-on-chronic liver (ACLF) are distinct phenotypes of liver failure and, thus, need to be compared and contrasted for appropriate management. There has been a significant improvement in the outcomes of these patients undergoing liver transplantation (LT). Survival post-LT for ALF and ACLF ranges between 90% and 95% and 80% and 90% at 1 year, futility criteria have been described in both ALF and ACLF where organ failures define survival. Plasma exchange and continuous renal replacement therapy may serve as bridging therapies. Identifying the futility of LT is as necessary as the utility of LT in patients with ALF and ACLF. The role of regenerative therapies such as granulocyte colony-stimulating factors in ACLF and hepatocyte and xenotransplantation in both conditions remains uncertain. Measures to increase the donor pool through increasing deceased donor transplants in Asian countries, living donations in Western countries, auxiliary liver transplants, and ABO-incompatible liver transplants are necessary to improve the survival of these patients. In this review, we discuss the similarities and differences in clinical characteristics and the timing and outcomes of LT for ALF and ACLF, briefly highlighting the role of bridging therapies and providing an overview of recent advances in the management of ALF and ACLF.

Cefepime-Induced Mixed Hepatocellular and Cholestatic Liver Injury: A Case Report

Drug-induced liver injury (DILI) presents significant diagnostic challenges, particularly in patients with multiple comorbidities. We report a case involving a 72-year-old female treated with cefepime for urosepsis, who developed markedly elevated liver enzymes after two weeks of therapy. After excluding other potential causes, including viral hepatitis, ischemia, and autoimmune hepatitis, cefepime-induced mixed pattern liver injury was determined to be the likely etiology of the elevated liver enzymes. This case underscores the importance of considering DILI in the differential diagnosis and emphasizes the necessity for vigilant monitoring and early recognition, particularly in elderly patients.

Multiscale X-ray phase-contrast CT uncovers adaptive changes and compensatory mechanisms of circulatory pathways during acute liver injury

Intrahepatic circulation is essential for the repair of acute liver injury (ALI); however, very limited information is available concerning changes in the circulatory pathways during ALI. Therefore, multi-scale X-ray phase-contrast CT combined with three-dimensional (3D) visualization is used to quantitatively analyze the intrahepatic circulation pathway (including the hepatic vein, portal vein and hepatic sinusoid) in the mouse model via the intraperitoneal injection of carbon tetrachloride (CCl4) from acute injury to recovery. The results demonstrate that the liver still preserves some vessel-like channels accessed to the central vein when the injury causes the severe collapse of the hepatic sinusoids that cannot be observed in two-dimensional pathologic slices. Moreover, angiogenesis is observed in the terminal branches of the hepatic vein and portal vein. Additionally, we extend the two-dimensional primary lobule to a 3D model and find that the sinusoids in zone III have the most severe injury. The sinusoids in different zones also show changes in parameters such as density and mean diameter during the ALI. In conclusion, phase-contrast CT can reveal the intact vascular system within the liver lobes, thus providing critical information for studying the mechanisms involved in the evolution of circulatory structures from damage to repair.

A Rare Case of Life-Threatening Jaundice Caused by Epstein-Barr Virus Infection and Secondary Cold Agglutinin Syndrome Successfully Treated with Rituximab

Background

Jaundice and hyperbilirubinemia are common clinical problems characterized by the presence of bile pigments in the blood and their deposition in body tissues. This clinical condition can be associated with a broad spectrum of potential benign and malignant causes, including hepatic inflammation, biliary obstruction, impaired bilirubin conjugation and bilirubin overproduction Therefore, the hyperbilirubinemia diagnostic work-up sometimes can be highly challenging and its therapeutic management can require a multidisciplinary approach.

Case Report

We report on a unique case of life-threatening jaundice and hepatic failure in a 20-year-old female who presented to the emergency room with complaints of fever, constant left abdominal pain and generalized profuse fatigue. A complete and detailed medical history, multiple tests for various infection, radiologic investigations and histological tests were performed in order to clarify the etiology of that rapidly progressive clinical condition. Based on the results, the patient jaundice was caused by an Epstein-Barr virus (EBV) infection and secondary cold agglutinin syndrome. Given the rare and complex diagnosis, multiple clinical specialists were asked to carry out the best patient management.

Conclusion

This rare case highlights how challenging the differential diagnosis and treatment of hyperbilirubinemia can be, presenting a unique case of life-threatening multifactorial hepatic failure treated successfully with rituximab.

Acacetin, a Natural Flavone with Potential in Improving Liver Disease Based on Its Anti-Inflammation, Anti-Cancer, Anti-Infection and Other Effects

Liver disease is a global public problem, and the cost of its therapy is a large financial burden to governments. It is well known that drug therapy plays a critical role in the treatment of liver disease. However, present drugs are far from meeting clinical needs. Lots of efforts have been made to find novel agents to treat liver disease in the past several decades. Acacetin is a dihydroxy and monomethoxy flavone, named 5,7-dihydroxy-4'-methoxyflavone, which can be found in diverse plants. It has been reported that acacetin exhibits multiple pharmacological activities, including anti-cancer, anti-inflammation, anti-virus, anti-obesity, and anti-oxidation. These studies indicate the therapeutic potential of acacetin in liver disease. This review discussed the comprehensive information on the pathogenesis of liver disease (cirrhosis, viral hepatitis, drug-induced liver injury, and hepatocellular carcinoma), then introduced the biological source, structural features, and pharmacological properties of acacetin, and the possible application in preventing liver disease along with the pharmacokinetic and toxicity of acacetin, and future research directions. We systemically summarized the latest research progress on the potential therapeutic effect of acacetin on liver disease and existing problems. Based on the present published information, the natural flavone acacetin is an anticipated candidate agent for the treatment of liver disease.

Artemether ameliorates acetaminophen-induced liver injury through Nrf2 pathway

Acetaminophen (APAP) overdose is a prevalent cause of clinical pharmacological liver injury worldwide. Artemether (ART), a first-line antimalarial drug, has demonstrated hepatoprotective activity. However, its effect on APAP-induced acute liver injury (AILI) remains unclear. In this study, we investigated whether ART can protect against AILI and examined its underlying mechanisms. In vivo, ART mitigated APAP-induced liver histological changes, including mitochondrial damage, hepatocyte necrosis, hepatocyte apoptosis, and inflammatory infiltration. Additionally, ART reduced serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels in APAP-induced mice. ART also activated the Nrf2-HO-1/GPX4 signaling pathway, exerting antioxidant effects in both in vitro and in vivo models of AILI. To confirm Nrf2 as a target of ART in vivo, we pretreated C57BL/6 mice with the Nrf2 inhibitor, ML385. The results indicated that inhibiting Nrf2 diminishes the protective effect of ART against AILI. Overall, our findings suggest that ART's protective effect against AILI is mediated through the Nrf2-related antioxidant pathway.

Hepsin as a potential therapeutic target for alleviating acetaminophen-induced hepatotoxicity via gap-junction regulation and oxidative stress modulation

Acetaminophen (APAP) overdose is a leading cause of drug-induced liver damage, highlighting the limitations of current emergency treatments that primarily involve administering the glutathione precursor N-acetylcysteine and supportive therapy. This study highlights the essential protective role of the type II transmembrane serine protease (TTSP), hepsin, in mitigating acetaminophen-induced liver injury, particularly through its regulation of gap junction (GJ) abundance in response to reactive oxygen stress in the liver. We previously reported that reduced levels of activated hepatocyte growth factor and the c-Met receptor tyrosine kinase-both of which are vital for maintaining cellular redox balance-combined with increased expression of GJ proteins in hepsin-deficient mice. Here, we show that hepsin deficiency in mice exacerbates acetaminophen toxicity compared to wild-type mice, leading to more severe liver pathology, elevated oxidative stress, and greater mortality within 6 h after exposure. Administering hepsin had a protective effect in both mouse models, reducing hepatotoxicity by modulating GJ abundance. Additionally, transcriptome analysis and a functional GJ inhibitor have highlighted hepsin's mechanism for managing oxidative stress. Combining hepsin with relatively low doses of N-acetylcysteine had a synergistic effect that was more efficacious than high-dose N-acetylcysteine alone. Our results illustrate the crucial role of hepsin in modulating the abundance of hepatic GJs and reducing oxidative stress, thereby offering early protection against acetaminophen-induced hepatotoxicity and a new, combination approach. Emerging as a promising therapeutic target, hepsin holds potential for combination therapy with N-acetylcysteine, paving the way for novel approaches in managing drug-induced liver injury.

Early brain neuroinflammatory and metabolic changes identified by dual tracer microPET imaging in mice with acute liver injury

Background

Acute liver injury (ALI) that progresses into acute liver failure (ALF) is a life-threatening condition with an increasing incidence and associated costs. Acetaminophen (N-acetyl-p-aminophenol, APAP) overdosing is among the leading causes of ALI and ALF in the Northern Hemisphere. Brain dysfunction defined as hepatic encephalopathy is one of the main diagnostic criteria for ALF. While neuroinflammation and brain metabolic alterations significantly contribute to hepatic encephalopathy, their evaluation at early stages of ALI remained challenging. To provide insights, we utilized post-mortem analysis and non-invasive brain micro positron emission tomography (microPET) imaging of mice with APAP-induced ALI.

Methods

Male C57BL/6 mice were treated with vehicle or APAP (600 mg/kg, i.p.). Serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), liver damage (using H&E staining), hepatic and serum IL-6 levels, and hippocampal IBA1 (using immunolabeling) were evaluated at 24h and 48h. Vehicle and APAP treated animals also underwent microPET imaging utilizing a dual tracer approach, including [11C]-peripheral benzodiazepine receptor ([11C]PBR28) to assess microglia/astrocyte activation and [18F]-fluoro-2-deoxy-2-D-glucose ([18F]FDG) to assess energy metabolism. Brain images were pre-processed and evaluated using conjunction and individual tracer uptake analysis.

Results

APAP-induced ALI and hepatic and systemic inflammation were detected at 24h and 48h by significantly elevated serum ALT and AST levels, hepatocellular damage, and increased hepatic and serum IL-6 levels. In parallel, increased microglial numbers, indicative for neuroinflammation were observed in the hippocampus of APAP-treated mice. MicroPET imaging revealed overlapping increases in [11C]PBR28 and [18F]FDG uptake in the hippocampus, thalamus, and habenular nucleus indicating microglial/astroglial activation and increased energy metabolism in APAP-treated mice (vs. vehicle-treated mice) at 24h. Similar significant increases were also found in the hypothalamus, thalamus, and cerebellum at 48h. The individual tracer uptake analyses (APAP vs vehicle) at 24h and 48h confirmed increases in these brain areas and indicated additional tracer- and region-specific effects including hippocampal alterations.

Conclusion

Peripheral manifestations of APAP-induced ALI in mice are associated with brain neuroinflammatory and metabolic alterations at relatively early stages of disease progression, which can be non-invasively evaluated using microPET imaging and conjunction analysis. These findings support further PET-based investigations of brain function in ALI/ALF that may inform timely therapeutic interventions.

Acute liver failure: A practical update

Acute liver failure is a rare and dynamic condition, with a broad aetiology and an incompletely understood pathophysiology. Management of this life-threatening disease requires critical care and organ support and frequently early liver transplantation. Proper identification, prevention and treatment of complications such as intracranial hypertension and sepsis are critical to optimising outcomes. The identification of the cause of acute liver failure and the prompt initiation of the aetiological treatment can also improve prognosis. Survival has progressively improved in parallel to advances in medical treatment. Intracranial hypertension complicating hepatic encephalopathy is less frequent than in the past and intracranial pressure monitoring now relies on non-invasive techniques. Current prognostic models have good accuracy to identify patients who will die without liver transplantation but are not able to identify those in whom transplantation is futile. New prognostic markers to select patients for transplantation are still in the pipeline. Therapeutic plasma exchange and, in some centers, early renal replacement therapy are well established treatments for the disease. The use of other artificial liver devices in clinical practice is not supported by evidence. This review is intended to provide a clinical update on the management of acute liver failure, incorporating the most recent advances in the field.

A High-Throughput Microphysiological Liver Chip System to Model Drug-Induced Liver Injury Using Human Liver Organoids

Background and Aims

Drug-induced liver injury (DILI) is a major failure mode in pharmaceutical development. This study aims to address the limitations of existing preclinical models by assessing a high-throughput, microfluidic liver-on-a-chip system, termed "Curio Barrier Liver Chips," and its capacity to recapitulate the effects of chronic hepatotoxic drug treatment through metabolic and phenotypic characterization.

Methods

Curio Barrier liver chips (Curiochips), fabricated in an 8 × 2 well configuration, were utilized to establish three dimensional liver organoid cultures. Human-induced pluripotent stem cells were differentiated into human liver organoids, and their viability, liver-specific functions, and pharmacological responses were assessed over 28 days.

Results

The Curiochips successfully maintained liver physiology and function, showing strong albumin secretion and cytochrome (CYP) P450 activities for 28 days. Unlike traditional models requiring millimolar drug concentrations to detect hepatotoxicity, this platform showed increased sensitivity for acetaminophen and fialuridine at micromolar concentrations. In situ differentiation of foregut spheroids to liver organoids was also achieved, further simplifying the establishment of liver chips. Furthermore, the chips demonstrated viability, function, and DILI responsiveness for 28 days, making this an improved model for studying idiosyncratic DILI with prolonged drug exposure and high-throughput capabilities compared to other available systems or primary human hepatocytes.

Conclusion

The Curiochips offer an advanced, miniaturized in vitro model for early-stage drug development and a sensitive, responsive, and cost-effective means to detect direct hepatotoxicity. Induced pluripotent stem cell liver organoids, in conjunction with the Curiochip, deliver a high-throughput platform with robust functionality and pharmacological responsiveness that make it a promising tool for improving the prediction and understanding of DILI risk prediction, especially with prolonged drug exposure. The model also opens new avenues for research in other chronic liver diseases.

Severe Acute Liver Injury After Hepatotoxic Medication Initiation in Real-World Data

IMPORTANCE

Current approaches to classify the hepatotoxic potential of medications are based on cumulative case reports of acute liver injury (ALI), which do not consider the size of the exposed population. There is little evidence from real-world data (data relating to patient health status and/or the delivery of health care routinely collected from sources outside of a research setting) on incidence rates of severe ALI after initiation of medications, accounting for duration of exposure.

OBJECTIVE

To identify the most potentially hepatotoxic medications based on real-world incidence rates of severe ALI and to examine how these rates compare with categorization based on case reports.

DESIGN, SETTING, AND PARTICIPANTS

This series of cohort studies obtained data from the US Department of Veterans Affairs on persons without preexisting liver or biliary disease who initiated a suspected hepatotoxic medication in the outpatient setting between October 1, 2000, and September 30, 2021. Data were analyzed from June 2020 to November 2023.

EXPOSURES

Outpatient initiation of any one of 194 medications with 4 or more published reports of hepatotoxicity.

MAIN OUTCOMES AND MEASURES

Hospitalization for severe ALI, defined by either inpatient: (1) alanine aminotransferase level greater than 120 U/L plus total bilirubin level greater than 2.0 mg/dL or (2) international normalized ratio of 1.5 or higher plus total bilirubin level greater than 2.0 mg/dL recorded within the first 2 days of admission. Acute or chronic liver or biliary disease diagnosis recorded during follow-up or as a discharge diagnosis of a hospitalization for severe ALI resulted in censoring. This study calculated age- and sex-adjusted incidence rates of severe ALI and compared observed rates with hepatotoxicity categories based on cumulative published case reports.

RESULTS

The study included 7 899 888 patients across 194 medication cohorts (mean [SD] age, 64.4 [16.4] years, 7 305 558 males [92.5%], 4 354 136 individuals [55.1%] had polypharmacy). Incidence rates of severe ALI ranged from 0 events per 10 000 person-years (candesartan, minocycline) to 86.4 events per 10 000 person-years (stavudine). Seven medications (stavudine, erlotinib, lenalidomide or thalidomide, chlorpromazine, metronidazole, prochlorperazine, and isoniazid) exhibited rates of 10.0 or more events per 10 000 person-years, and 10 (moxifloxacin, azathioprine, levofloxacin, clarithromycin, ketoconazole, fluconazole, captopril, amoxicillin-clavulanate, sulfamethoxazole-trimethoprim, and ciprofloxacin) had rates between 5.0 and 9.9 events per 10 000 person-years. Of these 17 medications with the highest observed rates of severe ALI, 11 (64%) were not included in the highest hepatotoxicity category when based on case reports.

CONCLUSIONS AND RELEVANCE

In this study, incidence rates of severe ALI using real-world data identified the most potentially hepatotoxic medications and can serve as a tool to investigate hepatotoxicity safety signals obtained from case reports. Case report counts did not accurately reflect the observed rates of severe ALI after medication initiation.

Effect of ferroptosis inhibitors in a murine model of acetaminophen-induced liver injury

Liver injury caused by acetaminophen (APAP) overdose is the leading cause of acute liver failure in western countries. The mode of APAP-induced cell death has been controversially discussed with ferroptosis emerging as a more recent hypothesis. Ferroptosis is characterized by ferrous iron-catalyzed lipid peroxidation (LPO) causing cell death, which can be prevented by the lipophilic antioxidants ferrostatin-1 and UAMC-3203. To assess the efficacy of these ferroptosis inhibitors, we used two murine models of APAP hepatotoxicity, APAP overdose alone or in combination with FeSO4 in fasted male C57BL/6J mice. APAP triggered severe liver injury in the absence of LPO measured as hepatic malondialdehyde (MDA) levels. In contrast, ferrous iron co-treatment aggravated APAP-induced liver injury and caused extensive LPO. Standard doses of ferrostatin-1 did not affect MDA levels or the injury in both models. In contrast, UAMC-3203 partially protected in both models and reduced LPO in the presence of ferrous iron. However, UAMC-3203 attenuated the translocation of phospho-JNK through downregulation of the mitochondrial anchor protein Sab resulting in reduced mitochondrial dysfunction and liver injury. Thus, APAP toxicity does not involve ferroptosis under normal conditions. The lack of effects of ferroptosis inhibitors in the pathophysiology indicates that ferroptosis signaling pathways are not relevant therapeutic targets.

Necrotic Liver Lesion Resolution: Another Mode of Liver Regeneration

The liver has the great ability to regenerate after partial resection or injury, and the mechanisms underlying liver regeneration have been extensively investigated. Interestingly, acute liver injuries triggered by various etiologies are associated with the formation of necrotic lesions, and such necrotic lesions are also rapidly resolved. However, how necrotic liver lesions are repaired has not been carefully investigated until recently. In this review, we briefly summarize the spatiotemporal process of necrotic liver lesion resolution in several liver injury models including immune-mediated liver injury and drug-induced liver injury. The roles of liver nonparenchymal cells and infiltrating immune cells in controlling necrotic liver lesion resolution are discussed, which may help identify potential therapies for acute liver injury and failure.

Preoperative risk evaluation and optimization for patients with liver disease

The prevalence of liver disease is rising and more patients with liver disease are considered for surgery each year. Liver disease poses many potential complications to surgery; therefore, assessing perioperative risk and optimizing a patient's liver health is necessary to decrease perioperative risk. Multiple scoring tools exist to help quantify perioperative risk and can be used in combination to best educate patients prior to surgery. In this review, we go over the various scoring tools and provide a guide for clinicians to best assess and optimize perioperative risk based on the etiology of liver disease.

No Significant Beneficial Effects of Intravenous N-Acetylcysteine on Patient Outcome in Non-Paracetamol Acute Liver Failure: A Meta-Analysis of Randomized Controlled Trials

Acute liver failure is a life-threatening organ dysfunction with systemic organ involvement and is associated with significant mortality and morbidity unless specific management is undertaken. This meta-analysis aimed to assess the effects of intravenous N-acetylcysteine (NAC) on mortality and the length of hospital stay in patients with non-acetaminophen acute liver failure. Two hundred sixty-six studies from four databases were screened, and four randomized control trials were included in the final analysis. Our results could not demonstrate increased overall survival (OR 0.70, 95% CI [0.34, 1.44], p = 0.33) or transplant-free survival (OR 0.90, 95% CI [0.25, 3.28], p = 0.87) in patients treated with intravenous NAC. We observed an increased overall survival in adult patients treated with NAC (OR 0.59, 95% CI [0.35, 0.99], p = 0.05) compared to pediatric patients, but whether this is attributed to the age group or higher intravenous dose administered remains unclear. We did not observe a decreased length of stay in NAC-treated patients (OR -5.70, 95% CI [-12.44, 1.05], p = 0.10). In conclusion, our meta-analysis could not demonstrate any significant benefits on overall and transplant-free patient survival in non-acetaminophen ALF. Future research should also focus on specific etiologies of ALF that may benefit most from the use of NAC.

Acute liver failure: Management update and prognosis

Acute liver failure is a rare but serious syndrome, with an incidence of approximately 2,000 to 3,000 cases per year in North America. Its pathophysiology and clinical course vary, depending on the cause of the primary liver injury, and can lead to high morbidity and mortality or the need for liver transplantation, despite available therapies. This syndrome involves excessive activation of the immune system, with damage in other organs, contributing to its high mortality rate. The most accepted definition includes liver injury with hepatic encephalopathy and coagulopathy within the past 26 weeks in a patient with no previous liver disease. The main causes are paracetamol poisoning, viral hepatitis, and drug-induced liver injury, among others. Identifying the cause is crucial, given that it influences prognosis and treatment. Survival has improved with supportive measures, intensive therapy, complication prevention, and the use of medications, such as N-acetylcysteine. Liver transplantation is a curative option for nonresponders to medical treatment, but adequate evaluation of transplantation timing is vital for improving results. Factors such as patient age, underlying cause, and severity of organ failure influence the post-transplant outcomes and survival.

Role of Gut Microecology in the Pathogenesis of Drug-Induced Liver Injury and Emerging Therapeutic Strategies

Drug-induced liver injury (DILI) is a common clinical pharmacogenic disease. In the United States and Europe, DILI is the most common cause of acute liver failure. Drugs can cause hepatic damage either directly through inherent hepatotoxic properties or indirectly by inducing oxidative stress, immune responses, and inflammatory processes. These pathways can culminate in hepatocyte necrosis. The role of the gut microecology in human health and diseases is well recognized. Recent studies have revealed that the imbalance in the gut microecology is closely related to the occurrence and development of DILI. The gut microecology plays an important role in liver injury caused by different drugs. Recent research has revealed significant changes in the composition, relative abundance, and distribution of gut microbiota in both patients and animal models with DILI. Imbalance in the gut microecology causes intestinal barrier destruction and microorganism translocation; the alteration in microbial metabolites may initiate or aggravate DILI, and regulation and control of intestinal microbiota can effectively mitigate drug-induced liver injury. In this paper, we provide an overview on the present knowledge of the mechanisms by which DILI occurs, the common drugs that cause DILI, the gut microbiota and gut barrier composition, and the effects of the gut microbiota and gut barrier on DILI, emphasizing the contribution of the gut microecology to DILI.

Continuous renal replacement therapy and survival in acute liver failure: A systematic review and meta-analysis

OBJECTIVE

Acute liver failure (ALF) is a rare syndrome leading to significant morbidity and mortality. An important cause of mortality is cerebral edema due to hyperammonemia. Different therapies for hyperammonemia have been assessed including continuous renal replacement therapy (CRRT). We conducted a systematic review and meta-analysis to determine the efficacy of CRRT in ALF patients.

MATERIALS AND METHODS

We searched MEDLINE, EMBASE, Cochrane Library, and Web of Science. Inclusion criteria included adult patients admitted to an ICU with ALF. Intervention was the use of CRRT for one or more indications with the comparator being standard care without the use of CRRT. Outcomes of interest were overall survival, transplant-free survival (TFS), mortality and changes in serum ammonia levels.

RESULTS

In total, 305 patients underwent CRRT while 1137 patients did not receive CRRT. CRRT was associated with improved overall survival [risk ratio (RR) 0.83, 95% confidence interval (CI) 0.70-0.99, p-value 0.04, I2 = 50%] and improved TFS (RR 0.65, 95% CI 0.49-0.85, p-value 0.002, I2 = 25%). There was a trend towards higher mortality with no CRRT (RR 1.24, 95% CI 0.84-1.81, p-value 0.28, I2 = 37%). Ammonia clearance data was unable to be pooled and was not analyzable.

CONCLUSION

Use of CRRT in ALF patients is associated with improved overall and transplant-free survival compared to no CRRT.

The thrombopoietin mimetic JNJ-26366821 reduces the late injury and accelerates the onset of liver recovery after acetaminophen-induced liver injury in mice

Acetaminophen (APAP)-induced hepatotoxicity is comprised of an injury and recovery phase. While pharmacological interventions, such as N-acetylcysteine (NAC) and 4-methylpyrazole (4-MP), prevent injury there are no therapeutics that promote recovery. JNJ-26366821 (TPOm) is a novel thrombopoietin mimetic peptide with no sequence homology to endogenous thrombopoietin (TPO). Endogenous thrombopoietin is produced by hepatocytes and the TPO receptor is present on liver sinusoidal endothelial cells in addition to megakaryocytes and platelets, and we hypothesize that TPOm activity at the TPO receptor in the liver provides a beneficial effect following liver injury. Therefore, we evaluated the extent to which TPOm, NAC or 4-MP can provide a protective and regenerative effect in the liver when administered 2 h after an APAP overdose of 300 mg/kg in fasted male C57BL/6J mice. TPOm did not affect protein adducts, oxidant stress, DNA fragmentation and hepatic necrosis up to 12 h after APAP. In contrast, TPOm treatment was beneficial at 24 h, i.e., all injury parameters were reduced by 42-48%. Importantly, TPOm enhanced proliferation by 100% as indicated by PCNA-positive hepatocytes around the area of necrosis. When TPOm treatment was delayed by 6 h, there was no effect on the injury, but a proliferative effect was still evident. In contrast, 4MP and NAC treated at 2 h after APAP significantly attenuated all injury parameters at 24 h but failed to enhance hepatocyte proliferation. Thus, TPOm arrests the progression of liver injury by 24 h after APAP and accelerates the onset of the proliferative response which is essential for liver recovery.

The chemokine CXCL14 is a novel early prognostic biomarker for poor outcome in acetaminophen-induced acute liver failure

BACKGROUND AND AIMS

Patients with acetaminophen-induced acute liver failure are more likely to die while on the liver transplant waiting list than those with other causes of acute liver failure. Therefore, there is an urgent need for prognostic biomarkers that can predict the need for liver transplantation early after an acetaminophen overdose.

APPROACH AND RESULTS

We evaluated the prognostic potential of plasma chemokine C-X-C motif ligand 14 (CXCL14) concentrations in patients with acetaminophen (APAP) overdose (n=50) and found that CXCL14 is significantly higher in nonsurviving patients compared to survivors with acute liver failure ( p < 0.001). Logistic regression and AUROC analyses revealed that CXCL14 outperformed the MELD score, better discriminating between nonsurvivors and survivors. We validated these data in a separate cohort of samples obtained from the Acute Liver Failure Study Group (n = 80), where MELD and CXCL14 had similar AUC (0.778), but CXCL14 demonstrated higher specificity (81.2 vs. 52.6) and positive predictive value (82.4 vs. 65.4) for death or need for liver transplantation. Next, combining the patient cohorts and using a machine learning training/testing scheme to mimic the clinical scenario, we found that CXCL14 outperformed MELD based on AUC (0.821 vs. 0.787); however, combining MELD and CXCL14 yielded the best AUC (0.860).

CONCLUSIONS

We find in 2 independent cohorts of acetaminophen overdose patients that circulating CXCL14 concentration is a novel early prognostic biomarker for poor outcomes, which may aid in guiding decisions regarding patient management. Moreover, our findings reveal that CXCL14 performs best when measured soon after patient presentation to the clinic, highlighting its importance for early warning of poor prognosis.

Interplay Between Drug-Induced Liver Injury and Gut Microbiota: A Comprehensive Overview

Drug-induced liver injury is a prevalent severe adverse event in clinical settings, leading to increased medical burdens for patients and presenting challenges for the development and commercialization of novel pharmaceuticals. Research has revealed a close association between gut microbiota and drug-induced liver injury in recent years. However, there has yet to be a consensus on the specific mechanism by which gut microbiota is involved in drug-induced liver injury. Gut microbiota may contribute to drug-induced liver injury by increasing intestinal permeability, disrupting intestinal metabolite homeostasis, and promoting inflammation and oxidative stress. Alterations in gut microbiota were found in drug-induced liver injury caused by antibiotics, psychotropic drugs, acetaminophen, antituberculosis drugs, and antithyroid drugs. Specific gut microbiota and their abundance are associated closely with the severity of drug-induced liver injury. Therefore, gut microbiota is expected to be a new target for the treatment of drug-induced liver injury. This review focuses on the association of gut microbiota with common hepatotoxic drugs and the potential mechanisms by which gut microbiota may contribute to the pathogenesis of drug-induced liver injury, providing a more comprehensive reference for the interaction between drug-induced liver injury and gut microbiota.

Cell Death in Liver Disease and Liver Surgery

Cell death is crucial for maintaining tissue balance and responding to diseases. However, under pathological conditions, the surge in dying cells results in an overwhelming presence of cell debris and the release of danger signals. In the liver, this gives rise to hepatic inflammation and hepatocellular cell death, which are key factors in various liver diseases caused by viruses, toxins, metabolic issues, or autoimmune factors. Both clinical and in vivo studies strongly affirm that hepatocyte death serves as a catalyst in the progression of liver disease. This advancement is characterized by successive stages of inflammation, fibrosis, and cirrhosis, culminating in a higher risk of tumor development. In this review, we explore pivotal forms of cell death, including apoptosis, pyroptosis, and necroptosis, examining their roles in both acute and chronic liver conditions, including liver cancer. Furthermore, we discuss the significance of cell death in liver surgery and ischemia-reperfusion injury. Our objective is to illuminate the molecular mechanisms governing cell death in liver diseases, as this understanding is crucial for identifying therapeutic opportunities aimed at modulating cell death pathways.

Acetaminophen-induced liver injury at therapeutic doses in a young adult: a case report

Acetaminophen causes volume-dependent hepatotoxicity; however, hepatotoxicity may also occur with acetaminophen administered at normal doses. We encountered a case of allergic liver damage in a 17-year-old girl receiving acetaminophen at a regular dose. The patient was diagnosed using the Roussel Uclaf Causality Assessment Method (RUCAM) and the diagnostic scale of the Digestive Disease Week Japan 2004 workshop. She tested positive for acetaminophen on a drug-induced lymphocyte stimulation test, and liver biopsy results confirmed the diagnosis of acetaminophen-induced liver injury. Despite administering acetaminophen at normal doses, hepatotoxicity may occur, which warrants further exploration.