Only in the darkness can you see the stars: Severe alcoholic hepatitis and higher grades of acute-on-chronic liver failure

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

BACKGROUND

Severe alcohol-associated hepatitis (SAH) patients with infections have a high short-term mortality rate. Gut microbiota dysbiosis plays an important role in the pathogenesis of SAH. Preliminary studies have demonstrated long-term benefits with healthy donor fecal microbiota transplantation (FMT). Data on FMT compared with pentoxifylline for SAH and relevant gut microbial changes are lacking in literature.

METHODS

From January 2019 to February 2021, retrospective analysis of a single hospital's records revealed 47 SAH patients undergoing FMT (100 mL/day via nasoduodenal tube for 7 days) and 25 matched patients receiving pentoxifylline (400 mg/8 h for 28 days). The primary end point was a 6-month survival rate. Secondary end points included incidence of ascites, hepatic encephalopathy, infections, acute kidney injury, and gut microbiota changes between post-therapy groups. Biomarker discovery and network analysis were also performed to identify significant taxa of gut microbiota in post-treatment groups in retrospectively stored stool samples.

RESULTS

All were males. The 6-month survival rate was higher in the patients undergoing FMT than in patients receiving pentoxifylline (83.0% vs 56.0%, P = 0.012). At the end of 6-month follow-up, the incidences of clinically significant ascites (56.0% vs 25.5%, P = 0.011), hepatic encephalopathy (40.0% vs 10.6%, P = 0.003), and critical infections (52.0% vs 14.9%, P < 0.001) in patients administered pentoxifylline were significantly higher than those in patients treated with FMT. At 3 months, biomarker analysis revealed a significant abundance of Bifidobacterium and Eggerthella in the FMT group and the pentoxifylline group, respectively. At 6 months, Bifidobacterium in the FMT group and pathogenic Aerococcaceae in the pentoxifylline group were notable. Network analysis showed beneficial taxa (Bifidobacterium) as a central influencer in those undergoing FMT at 6 months.

CONCLUSIONS

Healthy donor FMT improved survival rate and reduced liver-related complications compared with pentoxifylline. These clinical benefits were associated with favorable modulation of intestinal bacterial communities. Difficult-to-treat SAH patients may be safely bridged to transplantation using FMT. Controlled trials evaluating long-term outcomes are an unmet need.

The Mechanisms of Systemic Inflammatory and Immunosuppressive Acute-on-Chronic Liver Failure and Application Prospect of Single-Cell Sequencing

Acute-on-chronic liver failure (ACLF) is a complex clinical syndrome, and patients often have high short-term mortality. It occurs with intense systemic inflammation, often accompanied by a proinflammatory event (such as infection or alcoholic hepatitis), and is closely related to single or multiple organ failure. Liver inflammation begins when innate immune cells (such as Kupffer cells (KCs)) are activated by binding of pathogen-associated molecular patterns (PAMPs) from pathogenic microorganisms or damage-associated molecular patterns (DAMPs) of host origin to their pattern recognition receptors (PRRs). Activated KCs can secrete inflammatory factors as well as chemokines and recruit bone marrow-derived cells such as neutrophils and monocytes to the liver to enhance the inflammatory process. Bacterial translocation may contribute to ACLF when there are no obvious precipitating events. Immunometabolism plays an important role in the process (including mitochondrial dysfunction, amino acid metabolism, and lipid metabolism). The late stage of ACLF is mainly characterized by immunosuppression. In this process, the dysfunction of monocyte and macrophage is reflected in the downregulation of HLA-DR and upregulation of MER tyrosine kinase (MERTK), which weakens the antigen presentation function and reduces the secretion of inflammatory cytokines. We also describe the specific function of bacterial translocation and the gut-liver axis in the process of ACLF. Finally, we also describe the transcriptomics in HBV-ACLF and the recent progress of single-cell RNA sequencing as well as its potential application in the study of ACLF in the future, in order to gain a deeper understanding of ACLF in terms of single-cell gene expression.

Gut Microbiome and Alcohol-associated Liver Disease

Changes in gut microbiota (GM) may be associated with the causation and progression of multiple liver diseases such as metabolic-associated liver disease, alcohol-associated liver disease (ALD), alcohol-associated hepatitis (AH), primary biliary cholangitis, primary sclerosing cholangitis, autoimmune liver disease, and most importantly, complications of cirrhosis and portal hypertension such as hepatic encephalopathy (HE), infection, and hepatocellular carcinoma. ALD includes simple steatosis, steatohepatitis, AH, cirrhosis, and acute-on-chronic liver failure. Alcohol consumption is associated with GM changes even before ALD development, and continued alcohol intake results in progressive dysbiosis and development of clinical events such as AH, infection, and HE. The composition and function of GM, specific changes in bacterial communities, and the functional metabolism of GM are affected in the spectrum of ALD, as revealed using high-throughput sequencing. It was reported in preliminary studies that modulation of disrupted GM improves adverse clinical events and ameliorates disease progression in ALD. In this review, we exhaustively discuss the preclinical and clinical studies on GM in ALD and critically discuss GM modulation and its effects based on various human and animal models of ALD.

Long-term Outcomes of Stool Transplant in Alcohol-associated Hepatitis-Analysis of Clinical Outcomes, Relapse, Gut Microbiota and Comparisons with Standard Care

BACKGROUND

Healthy donor fecal microbiota transplantation (FMT) was preliminarily shown to have clinical benefits in hepatic encephalopathy (HE), severe alcohol-associated hepatitis (SAH), and alcohol use disorder. However, the long-term outcomes of FMT and the gut microbiota (GM) changes in patients with SAH are unknown.

METHODS

Patients with SAH who underwent FMT (N = 35) or standard of care (SoC, N = 26) from May 2017 to June 2018 were included, and their stored stool samples were analyzed prospectively. Clinical outcomes, including infections, hospitalizations, critical illness, alcohol relapse, and survival, were evaluated. Metagenomic analysis was undertaken to identify the relative abundances (Ras) and significant taxa at baseline and post-therapy (up to three years) among survivors between the two groups.

RESULTS

At follow-up, the incidences of ascites, HE, infections, and major hospitalizations were significantly higher in the SoC than in the FMT group (P < 0.05). Alcohol relapse was lower (28.6% versus 53.8%), and the time to relapse was higher in the FMT than in the SoC group (P = 0.04). Three-year survival was higher in the FMT than in the SoC group (65.7% versus 38.5%, P = 0.052). Death due to sepsis was significantly higher in the SoC group (N = 13/16, 81.2%; P = 0.008). GM analysis showed a significant increase in the RA of Bifidobacterium and a reduction in the RA of Acinetobacter in the FMT group. Beyond one to two years, the RA of Porphyromonas was significantly higher and that of Bifidobacterium was lower in the SoC than in the FMT group.

CONCLUSIONS

In terms of treatment for patients with SAH, healthy donor FMT is associated with significantly lesser ascites, infections, encephalopathy, and alcohol relapse (with a trend toward higher survival rates) than SoC, associated with beneficial GM modulation. Larger controlled studies on FMT are an unmet need.

Gut Barrier and Microbiota in Cirrhosis

Gut microbiota and their homeostatic functions are central to the maintenance of the intestinal mucosal barrier. The gut barrier functions as a structural, biological, and immunological barrier, preventing local and systemic invasion and inflammation of pathogenic taxa, resulting in the propagation or causation of organ-specific (liver disease) or systemic diseases (sepsis) in the host. In health, commensal bacteria are involved in regulating pathogenic bacteria, sinister bacterial products, and antigens; and help control and kill pathogenic organisms by secreting antimicrobial metabolites. Gut microbiota also participates in the extraction, synthesis, and absorption of nutrient metabolites, maintains intestinal epithelial integrity and regulates the development, homeostasis, and function of innate and adaptive immune cells. Cirrhosis is associated with local and systemic immune, vascular, and inflammatory changes directly or indirectly linked to perturbations in quality and quantity of intestinal microbiota and intestinal mucosal integrity. Dysbiosis and gut barrier dysfunction are directly involved in the pathogenesis of compensated cirrhosis and the type and severity of complications in decompensated cirrhosis, such as bacterial infections, encephalopathy, extrahepatic organ failure, and progression to acute on chronic liver failure. This paper reviews the normal gut barrier, gut barrier dysfunction, and dysbiosis-associated clinical events in patients with cirrhosis. The role of dietary interventions, antibiotics, prebiotics, probiotics, synbiotics, and healthy donor fecal microbiota transplantation (FMT) to modulate the gut microbiota for improving patient outcomes is further discussed.

Low Volume Plasma Exchange and Low Dose Steroid Improve Survival in Patients With Alcohol-Related Acute on Chronic Liver Failure and Severe Alcoholic Hepatitis - Preliminary Experience

Background

Alcohol-related acute on chronic liver failure (A-ACLF) patients have high short-term mortality and are poor candidates for steroid therapy. Plasma exchange (PLEX) improves survival in ACLF patients. We analyzed our experience with low volume PLEX (50% of plasma volume exchanged per session) and low dose steroids to treat A-ACLF patients.

Methods

We retrospectively compared the efficacy of low volume PLEX and low-dose steroids with standard medical treatment (SMT) in A-ACLF patients treated at our center between November 2017 to June 2019. The primary study outcome was one-year survival.

Results

Twenty-one A-ACLF patients in PLEX group [age 40 (29-56) years, median (range); MELD score 31 (29-46)] and 29 A-ACLF patients in SMT group [age 41.5 (28-63) years, MELD score 37 (21-48)] were studied. All 50 study patients had severe alcoholic hepatitis [mDF 84.7 (50-389)]. PLEX group patients had 3 (1-7) PLEX sessions with 1.5 (1.4-1.6) liters of plasma exchanged per session and oral Prednisolone 20 mg daily, tapered over 1 month. Kaplan Meier analysis showed better survival over 1 year in the PLEX group compared to the SMT group (P = 0.03). There was renal dysfunction in 10 patients in the PLEX group, which normalized in six patients after PLEX.

Conclusion

In this preliminary report, compared to SMT, low volume PLEX and low dose steroid improved survival over one year in A-ACLF patients with severe alcoholic hepatitis. In patients with renal dysfunction, 60% showed improvement in renal function with PLEX. Studies with a larger number of patients are needed to validate these results.

Update on diagnosis and management of sepsis in cirrhosis: Current advances

Sepsis and septic shock are catastrophic disease entities that portend high mortality in patients with cirrhosis. In cirrhosis, hemodynamic perturbations, immune dysregulation, and persistent systemic inflammation with altered gut microbiota in the background of portal hypertension enhance the risk of infections and resistance to antimicrobials. Patients with cirrhosis develop recurrent life-threatening infections that progress to multiple organ failure. The definition, pathophysiology, and treatment options for sepsis have been ever evolving. In this exhaustive review, we discuss novel advances in the understanding of sepsis, describe current and future biomarkers and scoring systems for sepsis, and delineate newer modalities and adjuvant therapies for the treatment of sepsis from existing literature to extrapolate the same concerning the management of sepsis in cirrhosis. We also provide insights into the role of gut microbiota in initiation and progression of sepsis and finally, propose a treatment algorithm for management of sepsis in patients with cirrhosis.

Acute-on-chronic liver failure: definition, prognosis and management

Acute-on-chronic liver failure (ACLF) is a recently described entity in chronic liver disease defined by acute hepatic decompensation, organ failure and a high risk of short-term mortality (usually less than 4 weeks). This condition is distinct from acute liver failure and stable progression of cirrhosis in numerous ways, including triggering precipitant factors, systemic inflammation, rapid progression and a potential for recovery. While a clear definition of ACLF has been forwarded from a large European Consortium study, some heterogeneity remains in how patients present and the types of organ failure, depending on whether they are described in Asian or European studies. Active alcoholism, acute alcoholic hepatitis and infections are the most frequent precipitants for ACLF. Underpinning the pathophysiology of ACLF is a state of persistent inflammation and immune dysfunction, collectively driving a systematic inflammatory response syndrome and an increased propensity to sepsis. Prevention and early treatment of organ failure are key in influencing survival. Given increasing organ shortage and more marginal grafts, liver transplantation is a limited resource and emphasises the need for new therapies to improve ACLF outcomes. Recent data indicate that liver transplantation has encouraging outcomes even in patients with advanced ACLF if patients are carefully selected during the permissive window of clinical presentation. ACLF remains a significant challenge in the field of hepatology, with considerable research and resource being channelled to improve upon the definition, prognostication, treatment and unravelling of mechanistic drivers. This Review discusses updates in ACLF definition, prognosis and management.

Severe alcoholic hepatitis: current perspectives

Severe acute alcoholic hepatitis (AH) is a catastrophic disease in the natural history of alcoholic liver disease with a very high 180-day mortality. It can present as acute on chronic liver failure with worse prognosis in the presence of infections and higher grades of liver disease severity. The clinical scenario involves a patient with a recent history of heavy alcohol consumption within three months of presentation with jaundice and characteristic liver enzyme elevation pattern with coagulopathy, hepatic encephalopathy, variceal bleeding and sepsis that results in extrahepatic organ failures. Several liver disease severities and therapy response indicators are in clinical use. Even though not approved, the only recommended treatment option for patients with severe AH is corticosteroids, which is without long term survival benefit. Novel efficacious treatment options awaiting high-quality multi-center studies include liver transplantation (involves strict selection criteria), growth factor therapy and fecal microbiota transplantation. In this exhaustive review, we discuss the definitions, disease severity, histopathology, and treatment options – past, present, and future, in patients with severe alcoholic hepatitis.