Clinical outcomes and gut microbiota analysis of severe alcohol-associated hepatitis patients undergoing healthy donor fecal transplant or pentoxifylline therapy: single-center experience from Kerala

Acute-on-chronic liver failure (ACLF): the 'Kyoto Consensus'-steps from Asia

Acute-on-chronic liver failure (ACLF) is a condition associated with high mortality in the absence of liver transplantation. There have been various definitions proposed worldwide. The first consensus report of the working party of the Asian Pacific Association for the Study of the Liver (APASL) set in 2004 on ACLF was published in 2009, and the "APASL ACLF Research Consortium (AARC)" was formed in 2012. The AARC database has prospectively collected nearly 10,500 cases of ACLF from various countries in the Asia-Pacific region. This database has been instrumental in developing the AARC score and grade of ACLF, the concept of the 'Golden Therapeutic Window', the 'transplant window', and plasmapheresis as a treatment modality. Also, the data has been key to identifying pediatric ACLF. The European Association for the Study of Liver-Chronic Liver Failure (EASL CLIF) and the North American Association for the Study of the End Stage Liver Disease (NACSELD) from the West added the concepts of organ failure and infection as precipitants for the development of ACLF and CLIF-Sequential Organ Failure Assessment (SOFA) and NACSELD scores for prognostication. The Chinese Group on the Study of Severe Hepatitis B (COSSH) added COSSH-ACLF criteria to manage hepatitis b virus-ACLF with and without cirrhosis. The literature supports these definitions to be equally effective in their respective cohorts in identifying patients with high mortality. To overcome the differences and to develop a global consensus, APASL took the initiative and invited the global stakeholders, including opinion leaders from Asia, EASL and AASLD, and other researchers in the field of ACLF to identify the key issues and develop an evidence-based consensus document. The consensus document was presented in a hybrid format at the APASL annual meeting in Kyoto in March 2024. The 'Kyoto APASL Consensus' presented below carries the final recommendations along with the relevant background information and areas requiring future studies.

Modulating the microbiome in chronic liver diseases - current evidence on the role of fecal microbiota transplantation

INTRODUCTION

The gut microbiota has a complex relationship with the human host and is key to maintaining health. Disruption of the healthy diverse gut microbial milieu plays an important role in the pathogenesis of several diseases including Clostridioides difficile infection (CDI), inflammatory bowel disease, irritable bowel syndrome, alcohol-related liver disease and metabolic-dysfunction associated steatotic liver disease (MASLD). Fecal microbiota transplantation (FMT) is highly effective in treating CDI, though its utility in other diseases is still being explored.

AREAS COVERED

In this narrative review, we explore the role of gut microbiota in liver diseases, focusing on key changes in the microbial composition and function. We summarize current evidence on the role of FMT, identifying gaps in current research and outlining future directions for investigation. We comprehensively searched PubMed through 15 October 2024 to identify relevant studies.

EXPERT OPINION

While data from available studies shows promise, more research is necessary before we can use FMT for liver diseases. Key areas that require further study are - determining the optimal FMT regimen for each disease, establishing efficacy and safety with larger clinical trials, ensuring safe and equitable access to the FMT product and mechanistic insights into the reasons for success or failure of FMT.

Alcohol-associated liver disease: Emerging therapeutic strategies

The large and growing burden of alcohol-associated liver disease-and the considerable burden of morbidity and mortality associated with it-has been a drive toward ongoing research into novel strategies for its treatment, with a particular focus upon alcohol-associated hepatitis (AH). Management of alcohol-use disorder forms the central pillar of alcohol-associated liver disease care, with evidence-based psychological and pharmacological approaches being well established, and certain models demonstrating improved clinical outcomes when hepatology and addiction services are co-located. Corticosteroids have previously been used somewhat indiscriminately in patients with severe AH, but effective tools now exist to assess early response (and limit futile ongoing exposure). Techniques to predict risk of corticosteroid-related infection are also available, although current clinical strategies to mitigate this risk are limited. A variety of novel therapeutic approaches to AH are at different phases of trials and evidence gathering, with some of the most promising signals related to cytokine manipulation, epigenetic modulation, and targeting of the gut microbiota (ie, by means of fecal microbiota transplant). While remaining an ongoing source of debate, early liver transplant in severe AH has grown in interest and acceptability over the past decade as evidence supporting its efficacy builds, in the process challenging paradigms about mandatory pretransplant sobriety periods. However, uncertainty remains regarding the optimal selection criteria, and whether liver transplant has a role for only a highly limited proportion of patients with AH or more widespread application. This review aims to provide an overview of this fast-moving field.

3PM-guided innovation in treatments of severe alcohol-associated hepatitis utilizing fecal microbiota transplantation

Rationale

Severe alcohol-associated hepatitis (SAH) is the most critical, acute, inflammatory phenotype within the alcohol-associated liver disease (ALD) spectrum, characterized by high 30- and 90-day mortality. Since several decades, corticosteroids (CS) are the only approved pharmacotherapy offering highly limited survival benefits. Contextually, there is an evident demand for 3PM innovation in the area meeting patients' needs and improving individual outcomes. Fecal microbiota transplantation (FMT) has emerged as one of the new potential therapeutic options. In this study, we aimed to address the crucial 3PM domains in order to assess (i) the impact of FMT on mortality in SAH patients beyond CS, (ii) to identify factors associated with the outcome to be improved (iii) the prediction of futility, (iv) prevention of suboptimal individual outcomes linked to increased mortality, and (v) personalized allocation of therapy.

Methods

We conducted a prospective study (NCT04758806) in adult patients with SAH who were non-responders (NR) to or non-eligible (NE) for CS between January 2018 and August 2022. The intervention consisted of five 100 ml of FMT, prepared from 30 g stool from an unrelated healthy donor and frozen at - 80 °C, administered daily to the upper gastrointestinal (GI) tract. We evaluated the impact of FMT on 30- and 90-day mortality which we compared to the control group selected by the propensity score matching and treated by the standard of care; the control group was derived from the RH7 registry of patients hospitalized at the liver unit (NCT04767945). We have also scrutinized the FMT outcome against established and potential prognostic factors for SAH - such as the model for end-stage liver disease (MELD), Maddrey Discriminant Function (MDF), acute-on-chronic liver failure (ACLF), Liver Frailty Index (LFI), hepatic venous-portal pressure gradient (HVPG) and Alcoholic Hepatitis Histologic Score (AHHS) - to see if the 3PM method assigns them a new dimension in predicting response to therapy, prevention of suboptimal individual outcomes, and personalized patient management.

Results

We enrolled 44 patients with SAH (NR or NE) on an intention-to-treat basis; we analyzed 33 patients per protocol for associated factors (after an additional 11 being excluded for receiving less than 5 doses of FMT), and 31 patients by propensity score matching for corresponding individual outcomes, respectively. The mean age was 49.6 years, 11 patients (33.3%) were females. The median MELD score was 29, and ACLF of any degree had 27 patients (81.8%). FMT improved 30-day mortality (p = 0.0204) and non-significantly improved 90-day mortality (p = 0.4386). Univariate analysis identified MELD ≥ 30, MDF ≥ 90, and ACLF grade > 1 as significant predictors of 30-day mortality, (p = 0.031; p = 0.014; p = 0.034). Survival was not associated with baseline LFI, HVPG, or AHHS.

Conclusions and recommendations in the framework of 3PM

In the most difficult-to-treat sub-cohort of patients with SAH (i.e., NR/NE), FMT improved 30-day mortality. Factors associated with benefit included MELD ≤ 30, MDF ≤ 90, and ACLF < 2. These results support the potential of gut microbiome as a therapeutic target in the context of 3PM research and vice versa - to use 3PM methodology as the expedient unifying template for microbiome research. The results allow for immediate impact on the innovative concepts of (i) personalized phenotyping and stratification of the disease for the clinical research and practice, (ii) multilevel predictive diagnosis related to personalized/precise treatment allocation including evidence-based (ii) prevention of futile and sub-optimally effective therapy, as well as (iii) targeted prevention of poor individual outcomes in patients with SAH. Moreover, our results add to the existing evidence with the potential to generate new research along the SAH's pathogenetic pathways such as diverse individual susceptibility to alcohol toxicity, host-specific mitochondrial function and systemic inflammation, and the role of gut dysbiosis thereof.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13167-024-00381-5.

A comprehensive review of diagnosis and management of alcohol-associated hepatitis

Alcohol-associated hepatitis is an extreme form of alcohol-related liver disease associated with high short-term mortality. Currently, there are no authorized therapies for the treatment of severe alcohol-associated hepatitis. Important diagnostic steps for alcohol-associated hepatitis include recognizing the presence of an alcohol use disorder, distinguishing alcohol-related liver disease from metabolic-dysfunction-associated steatotic liver disease, ruling out alternative causes of acute hepatitis, confirming the diagnosis with validated criteria or a liver biopsy, and using the model for end-stage liver disease score to predict clinical outcome and initiate therapy. Due to the lack of other effective therapy options, corticosteroids continue to be used as initial treatment for patients with severe alcohol-associated hepatitis. Patients who do not improve while on steroid treatment and are ideal candidates should be considered for curative liver transplantation as soon as possible. Avoiding unnecessary and ineffective pharmacological and interventional therapy can help to keep costs down. If a patient is not a good candidate for a transplant or is rapidly deteriorating in health due to a condition such as acute or chronic liver failure, a salvage/bridge to transplant should be pursued through enrolment in a clinical trial program. The role of healthy donor stool transplant and targeted bacteriophage therapy seems promising, pending prospective controlled trials.

Clinical outcomes and associated bacterial and fungal microbiota changes after high dose probiotic therapy for severe alcohol-associated hepatitis: An observational study

Alcohol-associated hepatitis (AH) is a critical condition with high mortality rates and is worsened by infections. Organ failure is strongly associated with intestinal dysbiosis. Emerging research suggests that gut microbiota modulation with probiotics can improve AH outcomes. This study investigated the clinical and microbiome effects of high-dose probiotic infusion (HDPI) compared with corticosteroid therapy (CST) and fecal microbiota transplantation (FMT) in severe AH. Patients with biopsy-proven severe-AH were enrolled from March 2019 to June 2020 and matched for age and disease severity. The patients received HDPI (n = 20), FMT (n = 16), or CST (n = 14). HDPI consists of a potent probiotic mix delivered via a nasoduodenal tube for 6 days. The primary outcome was survival at 90-days. Stool samples were subjected to 16S and 18S rRNA sequencing to assess significant bacterial and fungal taxa and their interactions at baseline and post treatment. At 90-days, survival rates were 55%, 64.3%, and 87.5% (HDPI, CST, respectively). HDPI did not beneficially impact bacterial alpha-diversity but significantly altered beta-diversity. Notably, the number of pathogenic bacteria, such as Bilophila and Roseburia increased. Fungal analysis revealed no significant changes in alpha diversity, but significant dissimilarities in beta diversity post-HDPI. New fungal genera such as Basidiomycota and Phragmoplastophyta have emerged, with significant deleterious expansion in fungal communities and damaging modifications between fungal-bacterial interactions. HDPI failed to outperform CST in improving the clinical outcomes of patients with severe AH. While HDPI influenced both bacterial and fungal microbiomes, it also led to the persistence of pathogenic communities. FMT showed superior survival outcomes, highlighting the urgent need for further controlled trials.

Emerging Pharmacologic Treatments for Alcohol-Associated Hepatitis: Current Status and Future Landscape

Several treatments have shown efficacy in preliminary alcohol-associated hepatitis trials. Interleukin-22 improved Model of End-stage Liver Disease score and aminotransferases in a phase II trial. The endogenous cholesterol derivative, larsucosterol, improved outcomes in a multi-center United States or European phase II trial. The antioxidants N-acetylcysteine and metadoxine improved survival in large trials. Trials from India report improved survival with granulocyte-colony stimulating factor, as well as improved outcome among patients receiving fecal microbiota transfer. Translational studies suggest that phage treatment of cytolytic Enterococcus faecalis may reduce liver injury.

Impact of fecal microbiota transplantation in severe alcoholic hepatitis: A systematic review and meta-analysis

Background and Aim

Severe alcoholic hepatitis (SAH) is a serious condition with few treatments. By modifying the gut-liver axis, fecal microbiota transplantation (FMT) was proposed as a treatment for SAH. The purpose of this meta-analysis was to evaluate the efficacy of FMT versus the standard of care (SOC) in improving SAH patient survival rates.

Methods

A thorough search of electronic databases was conducted till September 2023. The survival rates of SAH patients undergoing FMT versus SOC were compared. Using Review Manager 5.4, odds ratios (ORs) with 95% confidence intervals (CIs) were calculated.

Results

The meta-analysis consisted of six studies with a total of 371 patients with SAH. Patients who received FMT had significantly higher survival rates at 1 and 3 months compared to those who received SOC, with pooled OR of 2.91 (95% CI: 1.56-5.42, P = 0.0008) and 3.07 (95% CI: 1.81-5.20, P < 0.0001), respectively. However, the survival advantage disappeared after 6 months (OR: 2.96, 95% CI: 0.99-8.85, P = 0.05) and 1 year of follow-up (OR: 1.81, 95% CI: 0.44-7.46, P = 0.41).

Conclusion

This meta-analysis highlights the potential of FMT to significantly improve short-term survival rates in SAH patients. However, the survival benefit did not last 6-12 months. These findings call for additional research into the effectiveness of FMT over the long term, along with strategies for extending the survival benefit.

Fecal microbiota transplantation: current challenges and future landscapes

SUMMARYGiven the importance of gut microbial homeostasis in maintaining health, there has been considerable interest in developing innovative therapeutic strategies for restoring gut microbiota. One such approach, fecal microbiota transplantation (FMT), is the main "whole gut microbiome replacement" strategy and has been integrated into clinical practice guidelines for treating recurrent Clostridioides difficile infection (rCDI). Furthermore, the potential application of FMT in other indications such as inflammatory bowel disease (IBD), metabolic syndrome, and solid tumor malignancies is an area of intense interest and active research. However, the complex and variable nature of FMT makes it challenging to address its precise functionality and to assess clinical efficacy and safety in different disease contexts. In this review, we outline clinical applications, efficacy, durability, and safety of FMT and provide a comprehensive assessment of its procedural and administration aspects. The clinical applications of FMT in children and cancer immunotherapy are also described. We focus on data from human studies in IBD in contrast with rCDI to delineate the putative mechanisms of this treatment in IBD as a model, including colonization resistance and functional restoration through bacterial engraftment, modulating effects of virome/phageome, gut metabolome and host interactions, and immunoregulatory actions of FMT. Furthermore, we comprehensively review omics technologies, metagenomic approaches, and bioinformatics pipelines to characterize complex microbial communities and discuss their limitations. FMT regulatory challenges, ethical considerations, and pharmacomicrobiomics are also highlighted to shed light on future development of tailored microbiome-based therapeutics.

The Impact of Probiotic Bifidobacterium on Liver Diseases and the Microbiota

Recent studies have shown the promising potential of probiotics, especially the bacterial genus Bifidobacterium, in the treatment of liver diseases. In this work, a systematic review was conducted, with a focus on studies that employed advanced Next Generation Sequencing (NGS) technologies to explore the potential of Bifidobacterium as a probiotic for treating liver pathologies such as Non-Alcoholic Fatty Liver Disease (NAFLD), Non-Alcoholic Steatohepatitis (NASH), Alcoholic Liver Disease (ALD), Cirrhosis, and Hepatocelullar Carcinoma (HCC) and its impact on the microbiota. Our results indicate that Bifidobacterium is a safe and effective probiotic for treating liver lesions. It successfully restored balance to the intestinal microbiota and improved biochemical and clinical parameters in NAFLD, ALD, and Cirrhosis. No significant adverse effects were identified. While more research is needed to establish its efficacy in treating NASH and HCC, the evidence suggests that Bifidobacterium is a promising probiotic for managing liver lesions.

Role of fecal microbiota transplant in management of hepatic encephalopathy: Current trends and future directions

Fecal microbiota transplantation (FMT) offers a potential treatment avenue for hepatic encephalopathy (HE) by leveraging beneficial bacterial displacement to restore a balanced gut microbiome. The prevalence of HE varies with liver disease severity and comorbidities. HE pathogenesis involves ammonia toxicity, gut-brain communication disruption, and inflammation. FMT aims to restore gut microbiota balance, addressing these factors. FMT's efficacy has been explored in various conditions, including HE. Studies suggest that FMT can modulate gut microbiota, reduce ammonia levels, and alleviate inflammation. FMT has shown promise in alcohol-associated, hepatitis B and C-associated, and non-alcoholic fatty liver disease. Benefits include improved liver function, cognitive function, and the slowing of disease progression. However, larger, controlled studies are needed to validate its effectiveness in these contexts. Studies have shown cognitive improvements through FMT, with potential benefits in cirrhotic patients. Notably, trials have demonstrated reduced serious adverse events and cognitive enhancements in FMT arms compared to the standard of care. Although evidence is promising, challenges remain: Limited patient numbers, varied dosages, administration routes, and donor profiles. Further large-scale, controlled trials are essential to establish standardized guidelines and ensure FMT's clinical applications and efficacy. While FMT holds potential for HE management, ongoing research is needed to address these challenges, optimize protocols, and expand its availability as a therapeutic option for diverse hepatic conditions.

The gut-liver axis in hepatobiliary diseases

Recent advances in the analysis of intestinal bacteria have led to reports of variations in intestinal bacterial levels among hepatobiliary diseases. The mechanisms behind the changes in intestinal bacteria in various hepatobiliary diseases include the abnormal composition of intestinal bacteria, weakening of the intestinal barrier, and bacterial translocation outside the intestinal tract, along with their metabolites, but many aspects remain unresolved. Further research employing clinical studies and animal models is expected to clarify the direct relationship between intestinal bacteria and hepatobiliary diseases and to validate the utility of intestinal bacteria as a diagnostic biomarker and potential therapeutic target. This review summarizes the involvement of the microbiota in the pathogenesis of hepatobiliary diseases via the gut-liver axis.

The Role of Bifidobacterium in Liver Diseases: A Systematic Review of Next-Generation Sequencing Studies

The physiopathology of liver diseases is complex and can be caused by various factors. Bifidobacterium is a bacterial genus commonly found in the human gut microbiome and has been shown to influence the development of different stages of liver diseases significantly. This study investigated the relationship between the Bifidobacterium genus and liver injury. In this work, we performed a systematic review in major databases using the key terms "Bifidobacterium", "ALD", "NAFLD", "NASH", "cirrhosis", and "HCC" to achieve our purpose. In total, 31 articles were selected for analysis. In particular, we focused on studies that used next-generation sequencing (NGS) technologies. The studies focused on assessing Bifidobacterium levels in the diseases and interventional aimed at examining the therapeutic potential of Bifidobacterium in the mentioned conditions. Overall, the abundance of Bifidobacterium was reduced in hepatic pathologies. Low levels of Bifidobacterium were associated with harmful biochemical and physiological parameters, as well as an adverse clinical outcome. However, interventional studies using different drugs and treatments were able to increase the abundance of the genus and improve clinical outcomes. These results strongly support the hypothesis that changes in the abundance of Bifidobacterium significantly influence both the pathophysiology of hepatic diseases and the related clinical outcomes. In addition, our critical assessment of the NGS methods and related statistical analyses employed in each study highlights concerns with the methods used to define the differential abundance of Bifidobacterium, including potential biases and the omission of relevant information.

Significant gut microbiota related to patterns of drinking and alcohol relapse in patients with alcoholic hepatitis undergoing stool transplant or corticosteroid therapy

Alcohol-induced gut microbiota (GM) alterations are linked to alcohol use disorder (AUD) pathogenesis. Healthy donor stool transplant (fecal microbiota transplant [FMT]) reduced alcohol desire and improved clinical outcomes in small animal and human studies. Baseline and post-therapy-related GM changes in a real-world cohort with severe alcohol-related liver disease and AUD, patterns of drinking, and relapse have not been studied. We prospectively analyzed retrospective clinical data and stored samples to examine GM alterations in a cohort of severe alcohol-associated hepatitis (SAH) patients who underwent FMT or corticosteroid treatment followed for at least 12 months. The GM changes at baseline in the context of a pattern of drinking (binge vs. every day) and baseline and post-treatment alcohol relapse status (relapser vs. non-relapser). We identified 28 patients on FMT and 25 on corticosteroids who survived 1 year post-treatment. After necessary exclusions, the final cohort for various grouped GM analysis included 16 patients in the FMT arm and 14 on corticosteroids. Pedobacter and Streptophyta species at the commencement of treatment predicted alcohol relapse in steroid-ineligible patients receiving FMT and steroid-treated patients, respectively. At 6-12 months post-FMT, non-relapsers had elevated short-chain fatty acid-producing bacterial taxa linked with lower alcohol cravings. Alcohol relapse was significantly more in those on steroid therapy and was associated with the upregulation of the nucleotide metabolism pathway related to ethanol metabolism. We demonstrate pertinent baseline and post-treatment intestinal bacterial alterations that impact patterns of AUD patterns and relapse in SAH patients in the context of the therapy offered.

From-Toilet-to-Freezer: A Review on Requirements for an Automatic Protocol to Collect and Store Human Fecal Samples for Research Purposes

The composition, viability and metabolic functionality of intestinal microbiota play an important role in human health and disease. Studies on intestinal microbiota are often based on fecal samples, because these can be sampled in a non-invasive way, although procedures for sampling, processing and storage vary. This review presents factors to consider when developing an automated protocol for sampling, processing and storing fecal samples: donor inclusion criteria, urine-feces separation in smart toilets, homogenization, aliquoting, usage or type of buffer to dissolve and store fecal material, temperature and time for processing and storage and quality control. The lack of standardization and low-throughput of state-of-the-art fecal collection procedures promote a more automated protocol. Based on this review, an automated protocol is proposed. Fecal samples should be collected and immediately processed under anaerobic conditions at either room temperature (RT) for a maximum of 4 h or at 4 °C for no more than 24 h. Upon homogenization, preferably in the absence of added solvent to allow addition of a buffer of choice at a later stage, aliquots obtained should be stored at either -20 °C for up to a few months or -80 °C for a longer period-up to 2 years. Protocols for quality control should characterize microbial composition and viability as well as metabolic functionality.