The impact of rifaximin on inflammation and metabolism in alcoholic hepatitis: A randomized clinical trial

Antibiotics With or Without Rifaximin for Acute Hepatic Encephalopathy in Critically Ill Patients With Cirrhosis: A Double-Blind, Randomized Controlled (ARiE) Trial

INTRODUCTION

Critically ill patients with cirrhosis admitted to the intensive care unit (ICU) are usually on broad-spectrum antibiotics because of suspected infection or as a hospital protocol. It is unclear if additional rifaximin has any synergistic effect with broad-spectrum antibiotics in ICU patients with acute overt hepatic encephalopathy (HE).

METHODS

In this double-blind trial, patients with overt HE admitted to ICU were randomized to receive antibiotics (ab) alone or antibiotics with rifaximin (ab + r). Resolution (or 2 grade reduction) of HE, time to resolution of HE, in-hospital mortality, nosocomial infection, and changes in endotoxin levels were compared between the 2 groups. A subgroup analysis of patients with decompensated cirrhosis and acute-on-chronic liver failure was performed.

RESULTS

Baseline characteristics and severity scores were similar among both groups (92 in each group). Carbapenems and cephalosporin with beta-lactamase inhibitors were the most commonly used ab. On Kaplan-Meier analysis, 44.6% (41/92; 95% confidence interval [CI], 32-70.5) in ab-only arm and 46.7% (43/92; 95% CI, 33.8-63) in ab + r arm achieved the primary objective ( P = 0.84).Time to achieve the primary objective (3.65 ± 1.82 days and 4.11 ± 2.01 days; P = 0.27) and in-hospital mortality were similar among both groups (62% vs 50%; P = 0.13). Seven percent and 13% in the ab and ab + r groups developed nosocomial infections ( P = 0.21). Endotoxin levels were unaffected by rifaximin. Rifaximin led to lower in-hospital mortality (hazard ratio: 0.39 [95% CI, 0.2-0.76]) in patients with decompensated cirrhosis but not in patients with acute-on-chronic liver failure (hazard ratio: 0.99 [95% CI, 0.6-1.63]) because of reduced nosocomial infections.

DISCUSSION

Reversal of overt HE in those on ab was comparable with those on ab + r.

Gut-liver axis: Recent concepts in pathophysiology in alcohol-associated liver disease

The growing recognition of the role of the gut microbiome's impact on alcohol-associated diseases, especially in alcohol-associated liver disease, emphasizes the need to understand molecular mechanisms involved in governing organ-organ communication to identify novel avenues to combat alcohol-associated diseases. The gut-liver axis refers to the bidirectional communication and interaction between the gut and the liver. Intestinal microbiota plays a pivotal role in maintaining homeostasis within the gut-liver axis, and this axis plays a significant role in alcohol-associated liver disease. The intricate communication between intestine and liver involves communication between multiple cellular components in each organ that enable them to carry out their physiological functions. In this review, we focus on novel approaches to understanding how chronic alcohol exposure impacts the microbiome and individual cells within the liver and intestine, as well as the impact of ethanol on the molecular machinery required for intraorgan and interorgan communication.

Low sphingolipid levels predict poor survival in patients with alcohol-related liver disease

Background & Aims

Alcohol-related hepatitis (AH) and alcohol-related cirrhosis are grave conditions with poor prognoses. Altered hepatic lipid metabolism can impact disease development and varies between different alcohol-related liver diseases. Therefore, we aimed to investigate lipidomics and metabolomics at various stages of alcohol-related liver diseases and their correlation with survival.

Methods

Patients with newly diagnosed alcohol-related cirrhosis, who currently used alcohol (ALC-A), stable outpatients with decompensated alcohol-related cirrhosis with at least 8 weeks of alcohol abstinence (ALC), and patients with AH, were compared with each other and with healthy controls (HC). Circulating lipids and metabolites were analysed using HPLC and mass spectrometry.

Results

Forty patients with ALC, 95 with ALC-A, 30 with AH, and 42 HC provided plasma. Lipid levels changed according to disease severity, with generally lower levels in AH and cirrhosis than in the HC group; this was most pronounced for AH, followed by ALC-A. Nine out of 10 free fatty acids differed between cirrhosis groups by relative increases of 0.12-0.66 in ALC compared with the ALC-A group (p <0.0005). For metabolomics, total bile acids increased by 19.7, 31.3, and 80.4 in the ALC, ALC-A, and AH groups, respectively, compared with HC (all p <0.0001). Low sphingolipid ([d42:1] and [d41:1]) levels could not predict 180-day mortality (AUC = 0.73, p = 0.95 and AUC = 0.73, p = 0.95) more accurately than the model for end-stage liver disease score (AUC = 0.71), but did predict 90-day mortality (AUC d42:1 = 0.922, AUC d41:1 = 0.893; pd42:1 = 0.005, pd41:1 = 0.007) more accurately than the MELD score AUCMELD = 0.70, pMELD = 0.19).

Conclusions

Alcohol-related severe liver disease is characterised by low lipid levels progressing with severity of liver disease, especially low sphingomyelins, which also associate to poor prognoses.

Impact and implications

Lipidomics has the potential to diagnose and risk stratify patients with liver diseases. Lipidomics differed between patients with alcohol-related hepatitis and alcohol-related cirrhosis with and without recent alcohol use. Furthermore, lipidomics could predict short-term mortality and might be suitable as a prognostic tool in the future.

Clinical Trials Registration

Scientific Ethics Committee of the Capital Region of Denmark, journal no. H-21013476.

Past, Present, and Future Therapies for Alcohol-associated Hepatitis

PURPOSE

Alcohol-associated hepatitis (AH) is a unique presentation of cholestatic steatohepatitis with liver dysfunction and malaise preceded by heavy alcohol intake. Although AH exists on a spectrum, in its most severe form, 28-day mortality approaches 50%. Clinical trials of therapeutic interventions over the last 50 years have yielded few durable therapies, none of which convey benefit beyond the short term.

METHODS

A qualitative systematic review was performed via searches of PubMed, the International Clinical Trials Registry Platform, and ClinicalTrials.gov for therapeutic interventions for AH.

FINDINGS

Prior to 2005, clinical trial results for AH were identified within PubMed. From 2005 to the present, trials were well catalogued within online registries and included information regarding trial status (eg, complete, terminated, actively enrolling). Most clinical trials for AH have used existing medications broadly targeting pathogenic themes of AH (eg, inflammation, cell death) in an off-label manner. The trend of initially promising pilot studies answered by larger trials showing lack of efficacy or safety signals have ended the hopes of many new therapeutics. The emergence of theragnostics to identify patients who may benefit from existing therapies and trials of agents with novel mechanisms of action, including epigenetic modifications and hyaluronic acid signaling targeted to AH pathogenesis, are currently under investigation.

IMPLICATIONS

This review of AH treatments details the historical interventions and clinical trials that have led to the current treatment algorithm and active studies shaping the therapeutic pipeline for AH.

Intestinal Microbiotas and Alcoholic Hepatitis: Pathogenesis and Therapeutic Value

Alcoholic hepatitis (AH) is a rapidly progressing and severe stage of alcoholic liver disease, presenting a grim prognosis. Extensive research has elucidated several underlying mechanisms that contribute to the development of AH, including metabolic alterations, immune stimulation, and intestinal dysbiosis. These pathological changes intricately intertwine during the progression of AH. Notably, recent studies have increasingly highlighted the pivotal role of alterations in the intestinal microbiota in the pathogenesis of AH. Consequently, future investigations should place significant emphasis on exploring the dynamics of intestinal microbiota. In this comprehensive review, we consolidate the primary causes of AH while underscoring the influence of gut microbes. Furthermore, by examining AH treatment strategies, we delineate the potential therapeutic value of interventions targeting the gut microbiota. Given the existing limitations in AH treatment options, we anticipate that this review will contribute to forthcoming research endeavors aimed at advancing AH treatment modalities.

Gut Microbiome-Centered Therapies for Alcohol-Associated Liver Disease

Globally, liver disease caused by alcohol is becoming more prevalent each year. Misuse of alcohol causes a spectrum of liver diseases, such as liver steatosis, steatohepatitis, fibrosis, cirrhosis, and hepatocellular carcinoma. The cornerstone of treatment is abstinence from alcohol. In spite of this, available treatment for alcohol-associated liver disease (ALD) shows limited effectiveness currently. There are numerous ways in which alcohol disrupts the gut-liver axis, including dysbiosis of the gut microbiome, disruption of mucus and epithelial cell barriers, impaired production of antimicrobial molecules, and dysfunction of the immune system, causing translocation of viable microbes and microbial products to the liver and systemic circulation. Microbial exposure results in not only inflammation and progression of liver disease but also infections in late-stage ALD. This led scientists to focus their therapeutic strategies and targets for ALD on the gut microbiome. Throughout this review, we address the role of gut microbiome-centered therapeutic approaches for ALD focusing predominantly on randomized controlled trials. We will summarize the latest clinical trials using probiotics, antibiotics, and fecal microbial transplants in modulating the gut-liver axis and for improvement of ALD.

Rifaximin for prevention and treatment of hepatic encephalopathy in people with cirrhosis

BACKGROUND

Hepatic encephalopathy describes the spectrum of neuropsychiatric changes that may complicate the course of cirrhosis and detrimentally affect outcomes. Ammonia plays a key role in its development. Rifaximin is a non-absorbable antibiotic that inhibits urease-producing bacteria and reduces absorption of dietary and bacterial ammonia.

OBJECTIVES

To evaluate the beneficial and harmful effects of rifaximin versus placebo, no intervention, or non-absorbable disaccharides for: (i) the prevention of hepatic encephalopathy, and (ii) the treatment of minimal and overt hepatic encephalopathy, in people with cirrhosis, both when used alone and when combined with a non-absorbable disaccharide.

SEARCH METHODS

We searched the Cochrane Hepato-Biliary Group Clinical Trials Register, CENTRAL, MEDLINE, Embase, three other databases, the reference lists of identified papers, and relevant conference proceedings. We wrote to authors and pharmaceutical companies for information on other published, unpublished, or ongoing trials. Searches were performed to January 2023.

SELECTION CRITERIA

We included randomised clinical trials assessing prevention or treatment of hepatic encephalopathy with rifaximin alone, or with a non-absorbable disaccharide, versus placebo/no intervention, or a non-absorbable disaccharide alone.

DATA COLLECTION AND ANALYSIS

Six authors independently searched for studies, extracted data, and validated findings. We assessed the design, bias risk, and participant/intervention characteristics of the included studies. We assessed mortality, serious adverse events, health-related quality of life, hepatic encephalopathy, non-serious adverse events, blood ammonia, Number Connection Test-A, and length of hospital stay.

MAIN RESULTS

We included 41 trials involving 4545 people with, or at risk for, developing hepatic encephalopathy. We excluded 89 trials and identified 13 ongoing studies. Some trials involved participants with more than one type of hepatic encephalopathy or more than one treatment comparison. Hepatic encephalopathy was classed as acute (13 trials), chronic (7 trials), or minimal (8 trials), or else participants were considered at risk for its development (13 trials). The control groups received placebo (12 trials), no/standard treatment (1 trial), or a non-absorbable disaccharide (14 trials). Eighteen trials assessed rifaximin plus a non-absorbable disaccharide versus a non-absorbable disaccharide alone. We classified 11 trials as at high risk of overall bias for mortality and 28 for non-mortality outcomes, mainly due to lack of blinding, incomplete outcome data, and selective reporting. Compared to placebo/no intervention, rifaximin likely has no overall effect on mortality (risk ratio (RR) 0.83, 95% confidence interval (CI) 0.50 to 1.38; P = 48, I2 = 0%; 13 trials, 1007 participants; moderate-certainty evidence), and there may be no overall effect when compared to non-absorbable disaccharides (RR 0.99, 95% CI 0.49 to 1.97; P = 0.97, I2 = 0%; 10 trials, 786 participants; low-certainty evidence). However, there is likely a reduction in the overall risk of mortality when comparing rifaximin plus a non-absorbable disaccharide to a non-absorbable disaccharide alone (RR 0.69, 95% CI 0.55 to 0.86; number needed to treat for an additional beneficial outcome (NNTB) = 22; P = 0.001, I2 = 0%; 14 trials, 1946 participants; moderate-certainty evidence). There is likely no effect on the overall risk of serious adverse events when comparing rifaximin to placebo/no intervention (RR 1.05, 95% CI 0.83 to 1.32; P = 68, I2 = 0%; 9 trials, 801 participants; moderate-certainty evidence) and there may be no overall effect when compared to non-absorbable disaccharides (RR 0.97, 95% CI 0.66 to 1.40; P = 85, I2 = 0%; 8 trials, 681 participants; low-certainty evidence). However, there was very low-certainty evidence that use of rifaximin plus a non-absorbable disaccharide may be associated with a lower risk of serious adverse events than use of a non-absorbable disaccharide alone (RR 0.66, 95% CI 0.45 to 0.98; P = 0.04, I2 = 60%; 7 trials, 1076 participants). Rifaximin likely results in an overall effect on health-related quality of life when compared to placebo/no intervention (mean difference (MD) -1.43, 95% CI -2.87 to 0.02; P = 0.05, I2 = 81%; 4 trials, 214 participants; moderate-certainty evidence), and may benefit health-related quality of life in people with minimal hepatic encephalopathy (MD -2.07, 95% CI -2.79 to -1.35; P < 0.001, I2 = 0%; 3 trials, 176 participants). The overall effect on health-related quality of life when comparing rifaximin to non-absorbable disaccharides is very uncertain (MD -0.33, 95% CI -1.65 to 0.98; P = 0.62, I2 = 0%; 2 trials, 249 participants; very low-certainty evidence). None of the combined rifaximin/non-absorbable disaccharide trials reported on this outcome. There is likely an overall beneficial effect on hepatic encephalopathy when comparing rifaximin to placebo/no intervention (RR 0.56, 95% CI 0.42 to 0.77; NNTB = 5; P < 0.001, I2 = 68%; 13 trials, 1009 participants; moderate-certainty evidence). This effect may be more marked in people with minimal hepatic encephalopathy (RR 0.40, 95% CI 0.31 to 0.52; NNTB = 3; P < 0.001, I2 = 10%; 6 trials, 364 participants) and in prevention trials (RR 0.71, 95% CI 0.56 to 0.91; NNTB = 10; P = 0.007, I2 = 36%; 4 trials, 474 participants). There may be little overall effect on hepatic encephalopathy when comparing rifaximin to non-absorbable disaccharides (RR 0.85, 95% CI 0.69 to 1.05; P = 0.13, I2 = 0%; 13 trials, 921 participants; low-certainty evidence). However, there may be an overall beneficial effect on hepatic encephalopathy when comparing rifaximin plus a non-absorbable disaccharide to a non-absorbable disaccharide alone (RR 0.58, 95% CI 0.48 to 0.71; NNTB = 5; P < 0.001, I2 = 62%; 17 trials, 2332 participants; low-certainty evidence).

AUTHORS' CONCLUSIONS

Compared to placebo/no intervention, rifaximin likely improves health-related quality of life in people with minimal hepatic encephalopathy, and may improve hepatic encephalopathy, particularly in populations with minimal hepatic encephalopathy and when it is used for prevention. Rifaximin likely has no overall effect on mortality, serious adverse events, health-related quality of life, or hepatic encephalopathy compared to non-absorbable disaccharides. However, when used in combination with a non-absorbable disaccharide, it likely reduces overall mortality risk, the risk of serious adverse events, improves hepatic encephalopathy, reduces the length of hospital stay, and prevents the occurrence/recurrence of hepatic encephalopathy. The certainty of evidence for these outcomes is very low to moderate; further high-quality trials are needed.

Effect of Prophylactic Antibiotics on Mortality in Severe Alcohol-Related Hepatitis: A Randomized Clinical Trial

Importance

The benefits of prophylactic antibiotics for hospitalized patients with severe alcohol-related hepatitis are unclear.

Objective

To determine the efficacy of amoxicillin-clavulanate, compared with placebo, on mortality in patients hospitalized with severe alcohol-related hepatitis and treated with prednisolone.

Design, Setting, and Participants

Multicenter, randomized, double-blind clinical trial among patients with biopsy-proven severe alcohol-related hepatitis (Maddrey function score ≥32 and Model for End-stage Liver Disease [MELD] score ≥21) from June 13, 2015, to May 24, 2019, in 25 centers in France and Belgium. All patients were followed up for 180 days. Final follow-up occurred on November 19, 2019.

Intervention

Patients were randomly assigned (1:1 allocation) to receive prednisolone combined with amoxicillin-clavulanate (n = 145) or prednisolone combined with placebo (n = 147).

Main Outcome and Measures

The primary outcome was all-cause mortality at 60 days. Secondary outcomes were all-cause mortality at 90 and 180 days; incidence of infection, incidence of hepatorenal syndrome, and proportion of participants with a MELD score less than 17 at 60 days; and proportion of patients with a Lille score less than 0.45 at 7 days.

Results

Among 292 randomized patients (mean age, 52.8 [SD, 9.2] years; 80 [27.4%] women) 284 (97%) were analyzed. There was no significant difference in 60-day mortality between participants randomized to amoxicillin-clavulanate and those randomized to placebo (17.3% in the amoxicillin-clavulanate group and 21.3% in the placebo group [P = .33]; between-group difference, -4.7% [95% CI, -14.0% to 4.7%]; hazard ratio, 0.77 [95% CI, 0.45-1.31]). Infection rates at 60 days were significantly lower in the amoxicillin-clavulanate group (29.7% vs 41.5%; mean difference, -11.8% [95% CI, -23.0% to -0.7%]; subhazard ratio, 0.62; [95% CI, 0.41-0.91]; P = .02). There were no significant differences in any of the remaining 3 secondary outcomes. The most common serious adverse events were related to liver failure (25 in the amoxicillin-clavulanate group and 20 in the placebo group), infections (23 in the amoxicillin-clavulanate group and 46 in the placebo group), and gastrointestinal disorders (15 in the amoxicillin-clavulanate group and 21 in the placebo group).

Conclusion and Relevance

In patients hospitalized with severe alcohol-related hepatitis, amoxicillin-clavulanate combined with prednisolone did not improve 2-month survival compared with prednisolone alone. These results do not support prophylactic antibiotics to improve survival in patients hospitalized with severe alcohol-related hepatitis.

Trial Registration

ClinicalTrials.gov Identifier: NCT02281929.

Role of rifaximin in the management of alcohol-associated hepatitis: A systematic review and meta-analysis

BACKGROUND AND AIM

Alcohol-associated hepatitis (AAH) is an acute, inflammatory liver disease with severe short-term and long-term morbidity and mortality. AAH can lead to severe complications including hepatic failure, gastrointestinal bleeding, sepsis, and the development or decompensation of cirrhosis. Rifaximin is an antibiotic that reduces bacterial overgrowth and gut translocation, and it may have a role in decreasing systemic inflammation and infection in patients with AAH. Therefore, we conducted a systematic review and meta-analysis to evaluate the role of rifaximin in the management of AAH.

METHODS

A comprehensive search strategy was used to identify studies that met our inclusion criteria in Embase, MEDLINE (PubMed), Cochrane Library, Web of Science Core Collection, and Google Scholar. Outcomes of interest included rates of infection, 90-day mortality, and overall mortality between the rifaximin versus non-rifaximin group. Open Meta Analyst software was used to compute the results.

RESULTS

Three studies with a total of 162 patients were included in the final meta-analysis. Of the three studies, two were randomized control trials (RCTs), and one was a case-control study. There was a significantly lower rate of infection in the rifaximin group versus the non-rifaximin group (RR: 0.331, 95% CI: 0.159-0.689, I²  = 0%, P = 0.003). There was no significant difference in 90-day mortality in the rifaximin versus non-rifaximin group (RR: 0.743, 95% CI: 0.298-1.850, I²  = 24%, P = 0.523), nor was there a significant difference in overall mortality (RR: 0.624, 95% 95% CI: 0.299-1.3, I²  = 7.1%, P = 0.208).

CONCLUSIONS

The use of rifaximin in AAH is associated with a lower rate of infection rate than the non-rifaximin group. Additional research is needed to determine whether this effect is more pronounced in patients concurrently being treated with prednisolone. Differences in 90-day or overall mortality did not reach statistical significance. Further studies, particularly large randomized controlled trials, are needed to establish the role of rifaximin in AAH, especially as an adjunct therapy with prednisolone.

Potential therapies for acute-on-chronic liver failure

Acute-on-chronic liver failure (ACLF) is a syndrome that develops in approximately 30% of patients hospitalised with cirrhosis and is characterised by an acute decompensation of liver function associated with extra-hepatic organ failures and a high short-term mortality. At present, no specific therapies are available for ACLF, and current management is limited to treatment of the precipitating event and organ support. Given the high prevalence and high mortality of this severe liver disease, there is an urgent need for targeted treatments. There is increasing evidence of the important role played by systemic inflammation and immune dysfunction in the pathophysiology of ACLF and a better understanding of these immune processes is resulting in new therapeutic targets. The aim of this review is to present an overview of ongoing studies of potentially promising therapies and how they could be utilised in the management of ACLF.

Therapeutic targets in alcohol-associated liver disease: progress and challenges

Alcohol-associated liver disease (ALD) is a complex disease with rapidly increasing prevalence. Although there are promising therapeutic targets on the horizon, none of the newer targets is currently close to an Food and Drug Administration approval. Strategies are needed to overcome challenges in study designs and conducting clinical trials and provide impetus to the field of drug development in the landscape of ALD and alcoholic hepatitis. Management of ALD is complex and should include therapies to achieve and maintain alcohol abstinence, preferably delivered by a multidisciplinary team. Although associated with clear mortality benefit in select patients, the use of early liver transplantation still requires refinement to create uniformity in selection protocols across transplant centers. There is also a need for reliable noninvasive biomarkers for prognostication. Last but not the least, strategies are urgently needed to implement integrated multidisciplinary care models for treating the dual pathology of alcohol use disorder and of liver disease for improving the long-term outcomes of patients with ALD.

Role of gut bacterial and non-bacterial microbiota in alcohol-associated liver disease: Molecular mechanisms, biomarkers, and therapeutic prospective

Alcohol-associated liver disease (ALD) comprises a spectrum of liver diseases that include: steatosis to alcohol-associated hepatitis, cirrhosis, and ultimately hepatocellular carcinoma. The pathophysiology and potential underlying mechanisms for alcohol-associated liver disease are unclear. Moreover, the treatment of ALD remains a challenge. Intestinal microbiota include bacteria, fungi, and viruses, that are now known to be important in the development of ALD. Alcohol consumption can change the gut microbiota and function leading to liver disease. Given the importance of interactions between intestinal microbiota, alcohol, and liver injury, the gut microbiota has emerged as a potential biomarker and therapeutic target. This review focuses on the potential mechanisms by which the gut microbiota may be involved in the pathogenesis of ALD and explains how this can be translated into clinical management. We discuss the potential of utilizing the gut microbiota signature as a biomarker in ALD patients. Additionally, we present an overview of the prospect of modulating the intestinal microbiota for the management of ALD.