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Liver Biopsy in Patients With Alcohol-Associated Liver Disease With Acute-on-Chronic Liver Failure

  • Loretta Jophlin
    Affiliations
    Department of Gastroenterology and Hepatology, University of Louisville, Louisville, KY, USA
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  • Ashwani K. Singal
    Correspondence
    Address for correspondence:. Ashwani K. Singal, Professor of Medicine, University of South Dakota Sanford School of Medicine, Transplant Hepatologist and Chief Clinical Research Affairs, Avera McKennan University Hospital Transplant Institute, Sioux Falls, SD, 57105, USA. Tel.: +605 322-8545; fax: +605 322 8536.
    Affiliations
    Division of Gastroenterology and Hepatology, Department of Medicine, University of South Dakota Sanford School of Medicine, South Dakota, USA
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Published:August 13, 2021DOI:https://doi.org/10.1016/j.jceh.2021.08.009
      Patients with alcohol-associated liver disease may develop severe forms of presentation of acute-on-chronic liver failure, with a high risk for short-term mortality. Alcoholic hepatitis should be suspected among patients with alcohol-associated liver disease who present with acute-on-chronic liver failure. In this review, we discuss the need and feasibility of liver biopsy in the diagnosis of alcoholic hepatitis and predicting its prognosis among decompensated patients with alcohol-associated liver disease and acute-on-chronic liver failure.

      Keywords

      Abbreviations:

      AARC (Asia-Pacific ACLF Research Consortium), ACLF (acute-on-chronic liver failure), AH (alcoholic hepatitis), AHHS (alcoholic hepatitis histologic score), ALD (alcohol-associated liver disease), AUD (alcohol use disorder), DF (discriminant function), EtG (ethyl glucuronide), EUS (endoscopic ultrasound), NIAAA (National Institute on Alcoholism and Alcohol Abuse), PEth (phosphatidylethanol), SALVE (Study of Alcohol-related LiVer disease in Europe)
      Acute-on-chronic liver failure (ACLF) is a unique syndrome with sudden onset of hepatic decompensation among patients with chronic liver disease and/or cirrhosis. The criteria for diagnosis of ACLF are heterogeneous across the world,
      • Zaccherini G.
      • Weiss E.
      • Moreau R.
      Acute-on-chronic liver failure: definitions, pathophysiology and principles of treatment.
      ,
      • Singal A.K.
      • Kamath P.S.
      Acute on chronic liver failure in non-alcoholic fatty liver and alcohol associated liver disease.
      without consensus among the set of criteria proposed by different consortia (Table 1). However, the common factor connecting these definitions is a risk for high mortality irrespective of whichever criteria are used to define ACLF. For this review, we will exclude the ACLF definition proposed by the Chinese Group on the Study of Severe Hepatitis B as it focuses on hepatitis B virus-induced ACLF, and the criteria proposed by the North American Consortium for the Study of End-stage Liver Disease, as this definition only includes ACLF patients precipitated by infection. The Asia-Pacific ACLF Research Consortium (AARC) defines ACLF with the following set of criteria: serum bilirubin ≥5 mg/dL and INR ≥1.5 and development of clinical ascites and/or encephalopathy within 28 days in an individual with chronic liver disease or cirrhosis.
      • Sarin S.K.
      • Choudhury A.
      • Sharma M.K.
      • et al.
      Acute-on-chronic liver failure: consensus recommendations of the Asian Pacific association for the study of the liver (APASL): an update.
      The EASL-Chronic Liver Failure (CLIF) consortium defines ACLF in the presence of one or more of the six organ failures in an individual with cirrhosis.
      • Zaccherini G.
      • Weiss E.
      • Moreau R.
      Acute-on-chronic liver failure: definitions, pathophysiology and principles of treatment.
      A major difference is that EASL-CLIF proposes that the chronic component of ACLF be manifested by cirrhosis, whereas the AARC criteria include individuals with chronic liver disease with and without cirrhosis. In the EASL-CLIF CANONIC trial, ‘active alcoholism’ defined in individuals with active alcohol use within 3 months of presentation, was identified in 23% of subjects with ACLF and was strongly associated with ACLF severity.
      • Moreau R.
      • Jalan R.
      • Gines P.
      • et al.
      Acute-on-chronic liver failure is a distinct syndrome that develops in patients with acute decompensation of cirrhosis.
      Table 1Criteria to Define Acute-on-Chronic Liver Failure (ACLF) by Various Consortia.
      VariableAARCEASL-CLIFNACSELD
      Underlying liver diseaseCLD or cirrhosisCirrhosisCirrhosis
      Precipitating event/sAnyAnyOnly infection
      Liver failureBilirubin

      Ascites
      BilirubinNot included
      Renal failureCreatinine or RRTCreatinine or RRTOnly RRT
      Coagulation failureINRINRNot included
      Brain failureHE grade 3 or 4HE grade 3 or 4HE grade 3 or 4
      Respiratory failureNot includedPaO2/FiO2 <214

      Mechanical ventilation
      Mechanical ventilation
      Circulatory failureNot includedVasopressor/sMAP<60 or decrease in SBP by >40 mm Hg
      AARC: Asia-Pacific ACLF Research Consortium; CLIF: Chronic Liver Failure Consortium; NACSELD: North American Consortium for End-stage Liver Disease; CLD: Chronic Liver Disease; RRT: Renal Replacement Therapy; INR: International Normalized Ratio; HE: Hepatic Encephalopathy; MAP: Mean Arterial Pressure; SBP: Systolic Blood Pressure.

      Rationale in favor of liver biopsy for the detection of AH as a precipitant of ACLF

      ACLF in patients with alcohol-associated liver disease (ALD) could be due to acute alcoholic hepatitis (AH) superimposed on underlying advanced fibrosis or cirrhosis that is commonly present in these patients,
      • Singal A.K.
      • Louvet A.
      • Shah V.H.
      • Kamath P.S.
      Grand rounds: alcoholic hepatitis.
      ,
      • Sujan R.
      • Cruz-Lemini M.
      • Altamirano J.
      • et al.
      A validated score predicts acute kidney injury and survival in patients with alcoholic hepatitis.
      or be due to non-AH precipitants such as bacterial infection, gastrointestinal bleeding, drug-induced liver injury or toxic encephalopathy.
      • Singal A.K.
      • Kamath P.S.
      Acute on chronic liver failure in non-alcoholic fatty liver and alcohol associated liver disease.
      ,
      • Mookerjee R.P.
      • Lackner C.
      • Stauber R.
      • et al.
      The role of liver biopsy in the diagnosis and prognosis of patients with acute deterioration of alcoholic cirrhosis.
      • Gustot T.
      • Jalan R.
      Acute-on-chronic liver failure in patients with alcohol-related liver disease.
      • Singal A.K.
      • Arora S.
      • Wong R.J.
      • et al.
      Increasing burden of acute-on-chronic liver failure among alcohol-associated liver disease in the young population in the United States.
      Further, in a recent prospective study from the EASL-CLIF consortium, AH and/or bacterial infection were the most common precipitants of ACLF and were present in about 96% of patients with cirrhosis.
      • Trebicka J.
      • Fernandez J.
      • Papp M.
      • et al.
      PREDICT identifies precipitating events associated with the clinical course of acutely decompensated cirrhosis.
      The decision to make an accurate diagnosis of AH in an ACLF patient depends on whether the patient is eligible for specific AH treatment or for clinical trial enrollment.
      • Crabb D.W.
      • Bataller R.
      • Chalasani N.P.
      • et al.
      Standard definitions and common data elements for clinical trials in patients with alcoholic hepatitis: recommendation from the NIAAA alcoholic hepatitis consortia.
      • Mitchell M.C.
      • Friedman L.S.
      • McClain C.J.
      Medical management of severe alcoholic hepatitis: expert review from the clinical practice updates committee of the AGA Institute.
      • Singal A.K.
      • Bataller R.
      • Ahn J.
      • Kamath P.S.
      • Shah V.H.
      ACG clinical guideline: alcoholic liver disease.
      Corticosteroids are the only available specific pharmacological treatment for AH, with a short-term survival benefit of only about 50% for one month.
      • Singal A.K.
      • Bataller R.
      • Ahn J.
      • Kamath P.S.
      • Shah V.H.
      ACG clinical guideline: alcoholic liver disease.
      ,
      • Singh S.
      • Murad M.H.
      • Chandar A.K.
      • et al.
      Comparative effectiveness of pharmacological interventions for severe alcoholic hepatitis: a systematic review and network meta-analysis.
      Further, many severe AH patients may be ineligible for this therapy due to the presence of contraindications,
      • Singal A.K.
      • Salameh H.
      • Singal A.
      • et al.
      Management practices of hepatitis C virus infected alcoholic hepatitis patients: a survey of physicians.
      and even in eligible patients the response is observed in only 50–60% cases and cannot be predicted before initiation of treatment.
      • Louvet A.
      • Naveau S.
      • Abdelnour M.
      • et al.
      The Lille model: a new tool for therapeutic strategy in patients with severe alcoholic hepatitis treated with steroids.
      For example, a patient with ACLF in the ICU on mechanical ventilation, pressor, and dialysis would not be a candidate for corticosteroids or for enrollment in clinical trials evaluating newer therapeutic targets. In such cases, there is no need to obtain a liver biopsy to make a diagnosis of AH. In another scenario, a patient with coagulation failure and early encephalopathy not requiring ICU-level care may benefit from corticosteroid therapy if there are no contraindications. Such a patient would benefit from making an accurate diagnosis of AH. Among patients ineligible for steroids or clinical trials under consideration for early liver transplantation via an exception pathway (i.e. not requiring a minimum of six months abstinence), the treating physician may utilize liver biopsy for the diagnosis of AH on a case-by-case basis. For example, within the EASL-CLIF CANONIC prospective study, liver biopsy was performed in a minority, which limited accurate estimation of the true prevalence of AH in this study 4.

      Defining alcoholic hepatitis

      The definite diagnosis of AH requires a liver biopsy.
      • Singal A.K.
      • Louvet A.
      • Shah V.H.
      • Kamath P.S.
      Grand rounds: alcoholic hepatitis.
      ,
      • Axley P.
      • Russ K.
      • Singal A.K.
      Severe alcoholic hepatitis: atypical presentation with markedly elevated alkaline phosphatase.
      As it is invasive with risk of complications in patients with AH, especially those with ascites and/or coagulopathy,
      • Crabb D.W.
      • Bataller R.
      • Chalasani N.P.
      • et al.
      Standard definitions and common data elements for clinical trials in patients with alcoholic hepatitis: recommendation from the NIAAA alcoholic hepatitis consortia.
      ,
      • Rockey D.C.
      • Caldwell S.H.
      • Goodman Z.D.
      • Nelson R.C.
      • Smith A.D.
      American association for the study of liver D. Liver biopsy.
      biopsy is not performed by most centers and providers.
      • Singal A.K.
      • Salameh H.
      • Singal A.
      • et al.
      Management practices of hepatitis C virus infected alcoholic hepatitis patients: a survey of physicians.
      ,
      • Thursz M.R.
      • Richardson P.
      • Allison M.
      • et al.
      Prednisolone or pentoxifylline for alcoholic hepatitis.
      As such, the National Institute on Alcoholism and Alcohol Abuse (NIAAA) funded consortia using prospectively enrolled patients with AH developed criteria for the clinical diagnosis of AH.
      • Crabb D.W.
      • Bataller R.
      • Chalasani N.P.
      • et al.
      Standard definitions and common data elements for clinical trials in patients with alcoholic hepatitis: recommendation from the NIAAA alcoholic hepatitis consortia.
      These criteria are: onset of jaundice within 8 weeks (60 days) of last alcohol use, daily harmful alcohol use for 6 months or more, serum bilirubin (total) > 3.0 mg/dL, aspartate aminotransferase and alanine aminotransferase >50 and < 400 IU/L with aspartate aminotransferase/alanine aminotransferase >1.5, and exclusion of other causes of liver disease, including cholangitis and superimposed hepatocellular carcinoma. Of these criteria, the most challenging is inaccuracy and underreporting by the patient on alcohol consumption due to the social stigma associated with alcohol use disorder (AUD) and change in mental status due to alcohol withdrawal and/or hepatic encephalopathy.
      • Kranzler H.R.
      • Soyka M.
      Diagnosis and pharmacotherapy of alcohol use disorder: a review.
      ,
      • O'Connor E.A.
      • Perdue L.A.
      • Senger C.A.
      • et al.
      Screening and behavioral counseling interventions to reduce unhealthy alcohol use in adolescents and adults: updated evidence report and systematic review for the US preventive services task force.
      Self-reported information on alcohol use should be cross-checked with the family members, close friends, and other health-care providers.
      • Singal A.K.
      • Bataller R.
      • Ahn J.
      • Kamath P.S.
      • Shah V.H.
      ACG clinical guideline: alcoholic liver disease.
      ,
      • Mathurin P.
      • Lucey M.R.
      Liver transplantation in patients with alcohol-related liver disease: current status and future directions.
      In this regard, biomarkers of alcohol consumption can provide useful information and supplement the self-reported data.
      • Wozniak M.K.
      • Wiergowski M.
      • Namiesnik J.
      • Biziuk M.
      Biomarkers of alcohol consumption in body fluids - possibilities and limitations of application in toxicological analysis.
      Serum gamma-glutamyl transferase, AST, mean corpuscular volume, and carbohydrate-deficient transferrin are easily available but have low specificity to identify alcohol use.
      • Wozniak M.K.
      • Wiergowski M.
      • Namiesnik J.
      • Biziuk M.
      Biomarkers of alcohol consumption in body fluids - possibilities and limitations of application in toxicological analysis.
      • Staufer K.
      • Andresen H.
      • Vettorazzi E.
      • Tobias N.
      • Nashan B.
      • Sterneck M.
      Urinary ethyl glucuronide as a novel screening tool in patients pre- and post-liver transplantation improves detection of alcohol consumption.
      EASL Clinical Practice Guidelines on nutrition in chronic liver disease.
      Emerging biomarkers of alcohol metabolism like ethyl glucuronide (EtG) and phosphatidylethanol (PEth) are more accurate. Estimation of urinary level of EtG, a non-volatile water-soluble alcohol metabolite, can identify alcohol use over the last four days with a sensitivity of 62–89% and a specificity of 93–99%.
      • Singal A.K.
      • Bataller R.
      • Ahn J.
      • Kamath P.S.
      • Shah V.H.
      ACG clinical guideline: alcoholic liver disease.
      ,
      • Wozniak M.K.
      • Wiergowski M.
      • Namiesnik J.
      • Biziuk M.
      Biomarkers of alcohol consumption in body fluids - possibilities and limitations of application in toxicological analysis.
      • Staufer K.
      • Andresen H.
      • Vettorazzi E.
      • Tobias N.
      • Nashan B.
      • Sterneck M.
      Urinary ethyl glucuronide as a novel screening tool in patients pre- and post-liver transplantation improves detection of alcohol consumption.
      EASL Clinical Practice Guidelines on nutrition in chronic liver disease.
      • Fleming M.F.
      • Smith M.J.
      • Oslakovic E.
      • et al.
      Phosphatidylethanol detects moderate-to-heavy alcohol use in liver transplant recipients.
      PEth is a phospholipid metabolite of alcohol in the membrane of red blood cells and can identify the use of alcohol over the previous four weeks with a sensitivity of 90–99% and specificity of 100%.
      • Wozniak M.K.
      • Wiergowski M.
      • Namiesnik J.
      • Biziuk M.
      Biomarkers of alcohol consumption in body fluids - possibilities and limitations of application in toxicological analysis.
      ,
      EASL Clinical Practice Guidelines on nutrition in chronic liver disease.
      ,
      • Fleming M.F.
      • Smith M.J.
      • Oslakovic E.
      • et al.
      Phosphatidylethanol detects moderate-to-heavy alcohol use in liver transplant recipients.
      Given the rapid onset of ACLF (typically <4 weeks) and last alcohol drink required within 8 weeks of presentation, PEth may be cautiously used in these patients to determine if alcohol may be the precipitant.
      • Piano M.R.
      • Tiwari S.
      • Nevoral L.
      • Phillips S.A.
      Phosphatidylethanol levels are elevated and correlate strongly with AUDIT scores in young adult binge drinkers.
      ,
      • Simon T.W.
      Providing context for phosphatidylethanol as a biomarker of alcohol consumption with a pharmacokinetic model.
      Studies are needed to examine the utility of PEth for the diagnosis of AH. Another challenge in clinical diagnosis of AH is in excluding concomitant other causes of liver disease,
      • Russ K.B.
      • Chen N.W.
      • Kamath P.S.
      • Shah V.H.
      • Kuo Y.F.
      • Singal A.K.
      Alcohol use after liver transplantation is independent of liver disease etiology.
      especially chronic hepatitis C virus infection, which may be present in up to 25% of patients with chronic liver disease and/or cirrhosis.
      • Jamal M.M.
      • Saadi Z.
      • Morgan T.R.
      Alcohol and hepatitis C.
      • Singal A.K.
      • Anand B.S.
      Mechanisms of synergy between alcohol and hepatitis C virus.
      • Shoreibah M.
      • Anand B.S.
      • Singal A.K.
      Alcoholic hepatitis and concomitant hepatitis C virus infection.
      • Singal A.K.
      • Kuo Y.F.
      • Anand B.S.
      Hepatitis C virus infection in alcoholic hepatitis: prevalence patterns and impact on in-hospital mortality.
      It should be recognized that ALD and AH can occur at a lower amount of alcohol use in the presence of hepatitis C or B virus infections or other concomitant comorbidities such as obesity, type 2 diabetes mellitus, metabolic syndrome, or another chronic liver disease.
      • Altamirano J.
      • Michelena J.
      Alcohol consumption as a cofactor for other liver diseases.
      When all these criteria are met, it is reasonable to make a probable diagnosis of AH for specific pharmacological treatment with corticosteroids and/or inclusion in clinical trials. As the clinical diagnosis of AH may be inaccurate in 4–46% cases, especially when one or more of these criteria are not met,
      • Mookerjee R.P.
      • Lackner C.
      • Stauber R.
      • et al.
      The role of liver biopsy in the diagnosis and prognosis of patients with acute deterioration of alcoholic cirrhosis.
      ,
      • Hamid R.F.
      • Forrest E.H.
      Is histology required for the diagnosis of alcoholic hepatitis? a review of published randomized controlled trials.
      ,
      • Elphick D.A.
      • Dube A.K.
      • McFarlane E.
      • Jones J.
      • Gleeson D.
      Spectrum of liver histology in presumed decompensated alcoholic liver disease.
      such patients with possible AH should have a liver biopsy for making a diagnosis of definite AH. A liver biopsy may also be obtained depending on center or provider discretion among patients who qualify for a diagnosis of probable AH and meeting all the clinical criteria (Figure 1).
      Figure 1
      Figure 1Clinical criteria and role of liver biopsy for the diagnosis of alcoholic hepatitis (AH) among patients with alcohol-associated liver disease and acute-on-chronic liver failure (ACLF). ALT, alanine aminotransferase; AST, aspartate aminotransferase; GGT, Gamma-glutamyl transferase.

      Accuracy of clinical diagnosis of AH

      In a pooled dataset from 11 randomized clinical trials recruiting biopsy-proven AH patients, the accuracy of the clinical diagnosis of AH was 84.5%, and the accuracy increased to 96% among patients with bilirubin >4.7 mg/dL.
      • Hamid R.
      • Forrest E.H.
      Is histology required for the diagnosis of alcoholic hepatitis? a review of published randomised controlled trials.
      In a posthoc analysis of the largest randomized controlled trial in AH, the STOPAH trial, clinical diagnosis of AH was accurate in 80% of patients with severe AH (MELD score>20). This accuracy of clinical diagnosis increased to 100% in patients undergoing liver biopsy examination before administration of corticosteroids and baseline MELD score of ≥25.
      • Forrest E.
      • Petts G.
      • Austin A.
      • et al.
      The diagnostic and prognostic significance of liver histology in alcoholic hepatitis.
      In another study, white cell and platelet counts were helpful in making a more accurate diagnosis of AH.
      • Roth N.C.
      • Saberi B.
      • Macklin J.
      • et al.
      Prediction of histologic alcoholic hepatitis based on clinical presentation limits the need for liver biopsy.
      ,
      • Hardy T.
      • Wells C.
      • Kendrick S.
      • et al.
      White cell count and platelet count associate with histological alcoholic hepatitis in jaundiced harmful drinkers.
      For example, in a study on 68 patients with ALD and receiving liver biopsy (35 with AH on liver biopsy), white cell count <5.95 and platelet count <86 provided an 83% negative predictive value for excluding the diagnosis of AH, and white cell count of >10.95 and platelet count of >147.5 had a 100% positive predictive value in the diagnosis of AH.
      • Hardy T.
      • Wells C.
      • Kendrick S.
      • et al.
      White cell count and platelet count associate with histological alcoholic hepatitis in jaundiced harmful drinkers.

      Liver biopsy: technique and findings

      A transjugular approach is recommended to obtain the liver tissue, especially among patients with ascites and/or coagulopathy.
      • Singal A.K.
      • Louvet A.
      • Shah V.H.
      • Kamath P.S.
      Grand rounds: alcoholic hepatitis.
      ,
      • Singal A.K.
      • Bataller R.
      • Ahn J.
      • Kamath P.S.
      • Shah V.H.
      ACG clinical guideline: alcoholic liver disease.
      ,
      • Axley P.
      • Russ K.
      • Singal A.K.
      Severe alcoholic hepatitis: atypical presentation with markedly elevated alkaline phosphatase.
      ,
      • Rockey D.C.
      • Caldwell S.H.
      • Goodman Z.D.
      • Nelson R.C.
      • Smith A.D.
      American association for the study of liver D. Liver biopsy.
      ,
      • Lucey M.R.
      • Mathurin P.
      • Morgan T.R.
      Alcoholic hepatitis.
      Safety of liver biopsy in patients with decompensated liver disease especially those with ACLF, is also a concern. In an early report, open liver biopsy performed for the diagnosis of AH had 58% mortality related to biopsy.
      • Greenwood S.M.
      • Leffler C.T.
      • Minkowitz S.
      The increased mortality rate of open liver biopsy in alcoholic hepatitis.
      However, larger studies reported later have shown that a transjugular liver biopsy had acceptable success with low morbidity or mortality.
      • Kalambokis G.
      • Manousou P.
      • Vibhakorn S.
      • et al.
      Transjugular liver biopsy--indications, adequacy, quality of specimens, and complications--a systematic review.
      In a systematic review of 64 studies on 7649 subjects with any liver disease and undergoing transjugular liver biopsy, minor and major complications were reported in 6.5% and 0.6%, respectively. With a mortality rate of 0.09% in this pooled analysis, the outcomes were superior at centers with experience of performing >100 transjugular biopsies. With a median of three passes through the liver, the success rate in obtaining adequate tissue was 97%, which could provide a definite histological diagnosis in 96% of cases.
      • Kalambokis G.
      • Manousou P.
      • Vibhakorn S.
      • et al.
      Transjugular liver biopsy--indications, adequacy, quality of specimens, and complications--a systematic review.
      It should be recognized that the transjugular biopsy may only be available in specialized tertiary centers, as the technique requires expertise and infrastructure. Endoscopic ultrasound (EUS) guided liver biopsy is being increasingly used for liver biopsy, and allows for sampling of the right and left liver lobes.
      • Khurana S.
      • Butt W.
      • Khara H.S.
      • et al.
      Bi-lobar liver biopsy via EUS enhances the assessment of disease severity in patients with non-alcoholic steatohepatitis.
      While EUS-guided liver biopsy has a diagnostic yield comparable to the transjugular approach,
      • Mohan B.P.
      • Shakhatreh M.
      • Garg R.
      • Ponnada S.
      • Adler D.G.
      Efficacy and safety of EUS-guided liver biopsy: a systematic review and meta-analysis.
      ,
      • Bhogal N.
      • Lamb B.
      • Arbeiter B.
      • et al.
      Safety and adequacy of endoscopic ultrasound-guided random liver biopsy in comparison with transjugular and percutaneous approaches.
      these studies are limited with their retrospective design and inclusion of only 0–15% of patients with AH and/or cirrhosis. Clinical trials comparing the diagnostic yield, tissue quality, and safety of EUS-guided liver biopsy in AH patients are currently underway (Clinical trial identifier NCT04235855).
      When a liver biopsy is performed, the pathologist should examine for specific findings of AH such as macrovesicular steatosis, lobular neutrophils, hepatocyte injury with ballooning degeneration, and/or Mallory-Denk bodies, bilirubinostasis, and fibrosis in a pericellular or sinusoidal pattern (i.e. chicken wire fibrosis) (Figure 2).
      • Singal A.K.
      • Louvet A.
      • Shah V.H.
      • Kamath P.S.
      Grand rounds: alcoholic hepatitis.
      ,
      • Axley P.
      • Russ K.
      • Singal A.K.
      Severe alcoholic hepatitis: atypical presentation with markedly elevated alkaline phosphatase.
      ,
      • Lucey M.R.
      • Mathurin P.
      • Morgan T.R.
      Alcoholic hepatitis.
      ,
      • Arab J.P.
      • Roblero J.P.
      • Altamirano J.
      • et al.
      Alcohol-related liver disease: clinical practice guidelines by the Latin American association for the study of the liver (ALEH).
      Identification of underlying cirrhosis is important as its presence in AH patients negatively impacts the patient survival. However, there is interobserver variability of 42–100% in detection and staging of fibrosis on liver biopsy, including 15–20% sampling variation on the identification of cirrhosis on a liver biopsy.
      • Altamirano J.
      • Miquel R.
      • Katoonizadeh A.
      • et al.
      A histologic scoring system for prognosis of patients with alcoholic hepatitis.
      • Dubois M.
      • Sciarra A.
      • Trepo E.
      • et al.
      Histologic parameter score does not predict short-term survival in severe alcoholic hepatitis.
      • Horvath B.
      • Allende D.
      • Xie H.
      • et al.
      Interobserver variability in scoring liver biopsies with a diagnosis of alcoholic hepatitis.
      It is reported that the majority of AH patients have underlying cirrhosis, although the prevalence rates have varied from 30 to 100% in different series.
      • Singal A.K.
      • Louvet A.
      • Shah V.H.
      • Kamath P.S.
      Grand rounds: alcoholic hepatitis.
      ,
      • Sujan R.
      • Cruz-Lemini M.
      • Altamirano J.
      • et al.
      A validated score predicts acute kidney injury and survival in patients with alcoholic hepatitis.
      ,
      • Shetty S.
      • Venkatakrishnan L.
      • Krishanveni J.
      • Kumari S.
      Transjugular liver biopsy in severe alcoholic hepatitis.
      Figure 2
      Figure 2Liver biopsy findings of severe alcoholic hepatitis. Macrovesicular steatosis with Mallory hyaline (panel 1), intracanalicular and ductular cholestasis (panel 2), and neutrophilic infiltration of lobules and hepatocytes (panel 3), and advanced bridging fibrosis to evolving cirrhosis (panel 4). (Adapted from: Axley et al. J Clin Transl Hepatol 2017; 5: 1–2).
      The literature is conflicting regarding the role of liver biopsy in the diagnosis of AH.
      • Elphick D.A.
      • Dube A.K.
      • McFarlane E.
      • Jones J.
      • Gleeson D.
      Spectrum of liver histology in presumed decompensated alcoholic liver disease.
      ,
      • Roth N.C.
      • Saberi B.
      • Macklin J.
      • et al.
      Prediction of histologic alcoholic hepatitis based on clinical presentation limits the need for liver biopsy.
      ,
      • Greenwood S.M.
      • Leffler C.T.
      • Minkowitz S.
      The increased mortality rate of open liver biopsy in alcoholic hepatitis.
      ,
      • Shetty S.
      • Venkatakrishnan L.
      • Krishanveni J.
      • Kumari S.
      Transjugular liver biopsy in severe alcoholic hepatitis.
      • Bird G.L.
      Investigation of alcoholic liver disease.
      • Dhanda A.D.
      • Collins P.L.
      • McCune C.A.
      Is liver biopsy necessary in the management of alcoholic hepatitis?.
      • Haiar J.
      • Singal A.K.
      Editorial: liver biopsy in alcoholic hepatitis-more clarity on when it may be needed.
      One of the reasons for variability in the diagnosis of AH using liver biopsy is an interobserver variability between pathologists on specific findings of AH. For instance, bilirubinostasis has intraobserver agreement ranging from 52 to 86%.
      • Altamirano J.
      • Miquel R.
      • Katoonizadeh A.
      • et al.
      A histologic scoring system for prognosis of patients with alcoholic hepatitis.
      • Dubois M.
      • Sciarra A.
      • Trepo E.
      • et al.
      Histologic parameter score does not predict short-term survival in severe alcoholic hepatitis.
      • Horvath B.
      • Allende D.
      • Xie H.
      • et al.
      Interobserver variability in scoring liver biopsies with a diagnosis of alcoholic hepatitis.
      Similarly, interobserver variability has been reported for mega mitochondria (20%–46%)
      • Altamirano J.
      • Miquel R.
      • Katoonizadeh A.
      • et al.
      A histologic scoring system for prognosis of patients with alcoholic hepatitis.
      • Dubois M.
      • Sciarra A.
      • Trepo E.
      • et al.
      Histologic parameter score does not predict short-term survival in severe alcoholic hepatitis.
      • Horvath B.
      • Allende D.
      • Xie H.
      • et al.
      Interobserver variability in scoring liver biopsies with a diagnosis of alcoholic hepatitis.
      and hepatic steatosis (43–89%).
      • Roth N.C.
      • Saberi B.
      • Macklin J.
      • et al.
      Prediction of histologic alcoholic hepatitis based on clinical presentation limits the need for liver biopsy.
      ,
      • Horvath B.
      • Allende D.
      • Xie H.
      • et al.
      Interobserver variability in scoring liver biopsies with a diagnosis of alcoholic hepatitis.
      Of the various histological findings of AH, the agreement between pathologists is excellent for cholestasis, modest for neutrophilic lobular infiltration, and poor for mega mitochondria, with kappa statistics of 0.86, 0.6, and 0.46, respectively.
      • Altamirano J.
      • Miquel R.
      • Katoonizadeh A.
      • et al.
      A histologic scoring system for prognosis of patients with alcoholic hepatitis.
      In another study, the kappa statistics for agreement between pathologists on the interpretation of liver biopsy for histological findings of AH was 0.89 for steatosis, 0.60 for portal fibrosis, 0.65 for lobular inflammation, and 0.40 for hepatocyte ballooning.
      • Roth N.C.
      • Saberi B.
      • Macklin J.
      • et al.
      Prediction of histologic alcoholic hepatitis based on clinical presentation limits the need for liver biopsy.
      A recent study by the Study of Alcohol-related LiVer disease in Europe (SALVE) Histopathology Group on a multicenter cohort of 445 patients with ALD aimed at developing and validating a scoring system (SALVE grade) for ALD showed kappa statistics of 0.88 for steatosis and 0.66 for neutrophilic lobular infiltration.
      • Lackner C.
      • Stauber R.E.
      • Davies S.
      • et al.
      Development and prognostic relevance of a histologic grading and staging system for alcohol-related liver disease.
      The study showed that histological features of AH (hepatocyte ballooning and neutrophilic lobular infiltration) and severe cirrhosis (fibrosis assessment based on NASH CRN and Laennec’s staging systems) predicted survival and decompensation events in the short-term.
      • Lackner C.
      • Stauber R.E.
      • Davies S.
      • et al.
      Development and prognostic relevance of a histologic grading and staging system for alcohol-related liver disease.
      The histological findings should be interpreted in light of the clinical data, as histological findings of AH have been reported without the clinical phenotype of AH,
      • Mookerjee R.P.
      • Lackner C.
      • Stauber R.
      • et al.
      The role of liver biopsy in the diagnosis and prognosis of patients with acute deterioration of alcoholic cirrhosis.
      and have been known to be present in explants of liver transplant recipients for alcohol-associated cirrhosis after abstaining from alcohol for ≥6 months.
      • Wells J.T.
      • Said A.
      • Agni R.
      • et al.
      The impact of acute alcoholic hepatitis in the explanted recipient liver on outcome after liver transplantation.
      ,
      • Tome S.
      • Martinez-Rey C.
      • Gonzalez-Quintela A.
      • et al.
      Influence of superimposed alcoholic hepatitis on the outcome of liver transplantation for end-stage alcoholic liver disease.
      For accurate interpretation of histological findings of AH, at least five portal triads should be present, and the histology be independently interpreted by at least two pathologists with expertise in liver pathology. As the histological findings may change quickly after treatment with corticosteroids,
      • Forrest EP G.
      • Austin A.
      • Lloyd K.
      • et al.
      The diagnostic and prognostic significance of liver histology in alcoholic hepatitis.
      the liver tissue should ideally be examined before administration of corticosteroids. It may often be needed to send out the frozen sections to specialized centers with expertise in reading the liver tissue for findings of AH. This is often feasible as the histological findings of AH can persist for several months after alcohol cessation, thus providing a wide diagnostic window.
      • Hamid R.F.
      • Forrest E.H.
      Is histology required for the diagnosis of alcoholic hepatitis? a review of published randomized controlled trials.
      ,
      • Elphick D.A.
      • Dube A.K.
      • McFarlane E.
      • Jones J.
      • Gleeson D.
      Spectrum of liver histology in presumed decompensated alcoholic liver disease.
      ,
      • Wells J.T.
      • Said A.
      • Agni R.
      • et al.
      The impact of acute alcoholic hepatitis in the explanted recipient liver on outcome after liver transplantation.
      ,
      • Tome S.
      • Martinez-Rey C.
      • Gonzalez-Quintela A.
      • et al.
      Influence of superimposed alcoholic hepatitis on the outcome of liver transplantation for end-stage alcoholic liver disease.

      The prognostic role of liver biopsy in AH and ACLF

      Histological findings of AH have been used to estimate disease prognosis and response to medical treatment. In one study on AH patients recruited from multiple centers, the alcoholic hepatitis histologic score (AHHS) had a receiver operating characteristic value of 0.77 in predicting 90-day mortality, with mortality rates of 3%, 19%, and 51% at AHHS 0–3, 4–5, and 6–9 respectively.
      • Altamirano J.
      • Miquel R.
      • Katoonizadeh A.
      • et al.
      A histologic scoring system for prognosis of patients with alcoholic hepatitis.
      AHHS includes bilirubinostasis, fibrosis (presence and degree correlate with more severe disease), mega mitochondria, and neutrophilic infiltration (presence and degree correlate with less severe disease). Although increased serum white-blood-cell count confers a higher risk of mortality and acute kidney injury in patients with AH,
      • Sujan R.
      • Cruz-Lemini M.
      • Altamirano J.
      • et al.
      A validated score predicts acute kidney injury and survival in patients with alcoholic hepatitis.
      ,
      • Michelena J.
      • Altamirano J.
      • Abraldes J.G.
      • et al.
      Systemic inflammatory response and serum lipopolysaccharide levels predict multiple organ failure and death in alcoholic hepatitis.
      ,
      • Forrest E.H.
      • Evans C.D.
      • Stewart S.
      • et al.
      Analysis of factors predictive of mortality in alcoholic hepatitis and derivation and validation of the Glasgow alcoholic hepatitis score.
      neutrophilic infiltration within the liver lobules appears to have mixed effects. On the one hand, neutrophils are thought to cause persistent oxidative stress
      • Das S.
      • Maras J.S.
      • Hussain M.S.
      • et al.
      Hyperoxidized albumin modulates neutrophils to induce oxidative stress and inflammation in severe alcoholic hepatitis.
      and hepatic inflammation due to the formation of neutrophil extracellular traps,
      • Bukong T.N.
      • Cho Y.
      • Iracheta-Vellve A.
      • et al.
      Abnormal neutrophil traps and impaired efferocytosis contribute to liver injury and sepsis severity after binge alcohol use.
      however, they may also be hepato-protective due to their ability to clear necrotic hepatocytes and promote hepatic regeneration secondary to the release of hepatocyte growth factor.
      • Taieb J.
      • Delarche C.
      • Paradis V.
      • et al.
      Polymorphonuclear neutrophils are a source of hepatocyte growth factor in patients with severe alcoholic hepatitis.
      While the utility of AHHS in predicting mortality has been replicated in few other studies,
      • Forrest EP G.
      • Austin A.
      • Lloyd K.
      • et al.
      The diagnostic and prognostic significance of liver histology in alcoholic hepatitis.
      ,
      • Dubois M.
      • Sciarra A.
      • Trépo E.
      • et al.
      Histologic parameter score does not predict short-term survival in severe alcoholic hepatitis.
      the AHHS was not superior to the clinical non-invasive assessment, including MELD and modified discriminant function (DF) scores.
      • Altamirano J.
      • Miquel R.
      • Katoonizadeh A.
      • et al.
      A histologic scoring system for prognosis of patients with alcoholic hepatitis.
      ,
      • Forrest EP G.
      • Austin A.
      • Lloyd K.
      • et al.
      The diagnostic and prognostic significance of liver histology in alcoholic hepatitis.
      For individuals with moderate AH (MELD <21), the AHHS cut-off value of 5 has utility to discriminate 72% and 94% survival rates at 90 days.
      • Altamirano J.
      • Miquel R.
      • Katoonizadeh A.
      • et al.
      A histologic scoring system for prognosis of patients with alcoholic hepatitis.
      Further work is needed to determine if liver biopsy findings have a better prediction of disease severity and patient survival among patients with moderate AH (MELD 11–20) or DF < 32.
      Of the individual components of AH, bilirubinostasis has been shown to predict bacterial infections, sepsis, and mortality.
      • Altamirano J.
      • Miquel R.
      • Katoonizadeh A.
      • et al.
      A histologic scoring system for prognosis of patients with alcoholic hepatitis.
      ,
      • Katoonizadeh A.
      • Laleman W.
      • Verslype C.
      • et al.
      Early features of acute-on-chronic alcoholic liver failure: a prospective cohort study.
      The role of histology in predicting response to steroids remains controversial, with ballooning degeneration and Mallory-Denk bodies being associated with non-response to corticosteroids in one study,
      • Shasthry S.M.
      • Rastogi A.
      • Bihari C.
      • et al.
      Histological activity score on baseline liver biopsy can predict non-response to steroids in patients with severe alcoholic hepatitis.
      and lack of correlation of the AHHS in another study.
      • Altamirano J.
      • Miquel R.
      • Katoonizadeh A.
      • et al.
      A histologic scoring system for prognosis of patients with alcoholic hepatitis.
      More studies are needed to determine how liver biopsy can be utilized to guide treatment and inform prognosis in AH and ACLF.

      Non-invasive modalities

      Given the limitations of liver biopsy as described above, liquid liver biopsy with non-invasive biomarkers has emerged for the diagnosis of AH and predicting its prognosis
      • Shabangu C.S.
      • Huang J.F.
      • Hsiao H.H.
      • Yu M.L.
      • Chuang W.L.
      • Wang S.C.
      Liquid biopsy for the diagnosis of viral hepatitis, fatty liver steatosis, and alcoholic liver diseases.
      ,
      • Singal A.K.
      • Bailey S.M.
      Cellular abnormalities and emerging biomarkers in alcohol-associated liver disease.
      For example, levels of circulating extracellular vesicles have been shown to be three-fold elevated among patients with AH compared to healthy individuals.
      • Verma V.K.
      • Li H.
      • Wang R.
      • et al.
      Alcohol stimulates macrophage activation through caspase-dependent hepatocyte derived release of CD40L containing extracellular vesicles.
      In another study on AH patients, elevated levels of circulating exosomes and sphingolipid cargo within these vesicles improved the accuracy of the MELD score in predicting patient survival.
      • Sehrawat T.S.
      • Arab J.P.
      • Liu M.
      • et al.
      Circulating extracellular vesicles carrying sphingolipid cargo for the diagnosis and dynamic risk profiling of alcoholic hepatitis.
      Cytokeratin-18 released as a result of hepatocyte injury and its cleaved and uncleaved forms (M65 and M30) have also shown potential for diagnosis of AH, predicting prognosis, and response to medical treatment.
      • Atkinson S.R.
      • Grove J.I.
      • Liebig S.
      • et al.
      In severe alcoholic hepatitis, serum keratin-18 fragments are diagnostic, prognostic, and theragnostic biomarkers.
      Over the last few years, several other biomarkers have been derived for non-invasive diagnosis of AH and predicting prognosis in these patients. These biomarkers have been derived from: (a) serum: malondialdehyde,
      • Perez-Hernandez O.
      • Gonzalez-Reimers E.
      • Quintero-Platt G.
      • et al.
      Malondialdehyde as a prognostic factor in alcoholic hepatitis.
      osteopontin,
      • Morales-Ibanez O.
      • Dominguez M.
      • Ki S.H.
      • et al.
      Human and experimental evidence supporting a role for osteopontin in alcoholic hepatitis.
      CCL-20,
      • Singal A.K.
      • Bailey S.M.
      Cellular abnormalities and emerging biomarkers in alcohol-associated liver disease.
      ,
      • Affo S.
      • Morales-Ibanez O.
      • Rodrigo-Torres D.
      • et al.
      CCL20 mediates lipopolysaccharide induced liver injury and is a potential driver of inflammation and fibrosis in alcoholic hepatitis.
      and IL-6
      • Rachakonda V.
      • Gabbert C.
      • Raina A.
      • et al.
      Stratification of risk of death in severe acute alcoholic hepatitis using a panel of adipokines and cytokines.
      ; (b) stool: changes in the gut microbiota
      • Puri P.
      • Liangpunsakul S.
      • Christensen J.E.
      • et al.
      The circulating microbiome signature and inferred functional metagenomics in alcoholic hepatitis.
      ; (c) breath: trimethylamine, pentane, 2-propranolol, acetone, acetaldehyde, and ethanol
      • Hanouneh I.A.
      • Zein N.N.
      • Cikach F.
      • et al.
      The breathprints in patients with liver disease identify novel breath biomarkers in alcoholic hepatitis.
      ; (d) peripheral blood mononuclear cells: mitochondrial function and oxygen consumption rate
      • Singal A.K.
      • Bailey S.M.
      Cellular abnormalities and emerging biomarkers in alcohol-associated liver disease.
      ,
      • Chacko B.K.
      • Kramer P.A.
      • Ravi S.
      • et al.
      The Bioenergetic Health Index: a new concept in mitochondrial translational research.
      ; and (e) isolated DNA: genetic polymorphisms of patatin-like phospholipase domain protein 3 (PNPLA3), TM6SF2, MBOAT7, and HSD17B13.
      • Salameh H.
      • Raff E.
      • Erwin A.
      • et al.
      PNPLA3 gene polymorphism is associated with predisposition to and severity of alcoholic liver disease.
      • Liangpunsakul S.
      • Beaudoin J.J.
      • Shah V.H.
      • et al.
      Interaction between the patatin-like phospholipase domain-containing protein 3 genotype and coffee drinking and the risk for acute alcoholic hepatitis.
      • Atkinson S.R.
      • Way M.J.
      • McQuillin A.
      • Morgan M.Y.
      • Thursz M.R.
      Homozygosity for rs738409:G in PNPLA3 is associated with increased mortality following an episode of severe alcoholic hepatitis.
      • Kirpich I.A.
      • Warner D.R.
      • Feng W.
      • et al.
      Mechanisms, biomarkers and targets for therapy in alcohol-associated liver injury: from Genetics to nutrition: summary of the ISBRA 2018 symposium.
      Among patients with decompensated ALD and ACLF, there should be a low threshold for suspecting AH. Although the clinical diagnosis of AH has improved using the criteria proposed by the NIAAA, a liver biopsy may be needed among patients with uncertain clinical diagnoses. A transjugular route is preferred in these sick patients with ascites and/or coagulopathy. While data are conflicting on the role of liver biopsy in predicting disease severity and patient survival, several non-invasive biomarkers are emerging. Lack of validation, technical difficulties, lack of widespread availability, and high cost, however, limit their current use in routine clinical practice.
      • Singal A.K.
      • Bailey S.M.
      Cellular abnormalities and emerging biomarkers in alcohol-associated liver disease.
      ,
      • Kirpich I.A.
      • Warner D.R.
      • Feng W.
      • et al.
      Mechanisms, biomarkers and targets for therapy in alcohol-associated liver injury: from Genetics to nutrition: summary of the ISBRA 2018 symposium.
      In conclusion, liver biopsy should be considered on a case-by-case basis for ALD patients presenting with ACLF and a possible or probable diagnosis of AH. Clearly, the data gathered from ongoing clinical trials will be useful to further substantiate the role of liver biopsy for the diagnosis of AH and predicting its prognosis. The clinical trajectories of patients with biopsy-proven, definite AH in the setting of ACLF should define the role of liver biopsy in guiding therapy and prognosis of patients with ALD and ACLF.

      Credit authorship contribution statement

      Loretta Jophlin developed the initial draft and searched the literature for the review. AKS reviewed the draft and added intellectual content to the review. Both the authors reviewed and approved the final draft.

      Conflicts of interest

      The authors have none to declare.

      Source of funding

      None.

      References

        • Zaccherini G.
        • Weiss E.
        • Moreau R.
        Acute-on-chronic liver failure: definitions, pathophysiology and principles of treatment.
        JHEP Rep. 2021; 3: 100176
        • Singal A.K.
        • Kamath P.S.
        Acute on chronic liver failure in non-alcoholic fatty liver and alcohol associated liver disease.
        Transl Gastroenterol Hepatol. 2019; 4: 74
        • Sarin S.K.
        • Choudhury A.
        • Sharma M.K.
        • et al.
        Acute-on-chronic liver failure: consensus recommendations of the Asian Pacific association for the study of the liver (APASL): an update.
        Hepatol Int. 2019; 13: 353-390
        • Moreau R.
        • Jalan R.
        • Gines P.
        • et al.
        Acute-on-chronic liver failure is a distinct syndrome that develops in patients with acute decompensation of cirrhosis.
        Gastroenterology. 2013; 144 (1437 e1421-1429): 1426-1437
        • Singal A.K.
        • Louvet A.
        • Shah V.H.
        • Kamath P.S.
        Grand rounds: alcoholic hepatitis.
        J Hepatol. 2018; 69: 534-543
        • Sujan R.
        • Cruz-Lemini M.
        • Altamirano J.
        • et al.
        A validated score predicts acute kidney injury and survival in patients with alcoholic hepatitis.
        Liver Transpl. 2018; 24: 1655-1664
        • Mookerjee R.P.
        • Lackner C.
        • Stauber R.
        • et al.
        The role of liver biopsy in the diagnosis and prognosis of patients with acute deterioration of alcoholic cirrhosis.
        J Hepatol. 2011; 55: 1103-1111
        • Gustot T.
        • Jalan R.
        Acute-on-chronic liver failure in patients with alcohol-related liver disease.
        J Hepatol. 2019; 70: 319-327
        • Singal A.K.
        • Arora S.
        • Wong R.J.
        • et al.
        Increasing burden of acute-on-chronic liver failure among alcohol-associated liver disease in the young population in the United States.
        Am J Gastroenterol. 2020; 115: 88-95
        • Trebicka J.
        • Fernandez J.
        • Papp M.
        • et al.
        PREDICT identifies precipitating events associated with the clinical course of acutely decompensated cirrhosis.
        J Hepatol. 2021; 74: 1097-1108
        • Crabb D.W.
        • Bataller R.
        • Chalasani N.P.
        • et al.
        Standard definitions and common data elements for clinical trials in patients with alcoholic hepatitis: recommendation from the NIAAA alcoholic hepatitis consortia.
        Gastroenterology. 2016; 150: 785-790
        • Mitchell M.C.
        • Friedman L.S.
        • McClain C.J.
        Medical management of severe alcoholic hepatitis: expert review from the clinical practice updates committee of the AGA Institute.
        Clin Gastroenterol Hepatol. 2017; 15: 5-12
        • Singal A.K.
        • Bataller R.
        • Ahn J.
        • Kamath P.S.
        • Shah V.H.
        ACG clinical guideline: alcoholic liver disease.
        Am J Gastroenterol. 2018; 113: 175-194
        • Singh S.
        • Murad M.H.
        • Chandar A.K.
        • et al.
        Comparative effectiveness of pharmacological interventions for severe alcoholic hepatitis: a systematic review and network meta-analysis.
        Gastroenterology. 2015; 149 (e912): 958-970
        • Singal A.K.
        • Salameh H.
        • Singal A.
        • et al.
        Management practices of hepatitis C virus infected alcoholic hepatitis patients: a survey of physicians.
        World J Gastrointest Pharmacol Ther. 2013; 4: 16-22
        • Louvet A.
        • Naveau S.
        • Abdelnour M.
        • et al.
        The Lille model: a new tool for therapeutic strategy in patients with severe alcoholic hepatitis treated with steroids.
        Hepatology. 2007; 45: 1348-1354
        • Axley P.
        • Russ K.
        • Singal A.K.
        Severe alcoholic hepatitis: atypical presentation with markedly elevated alkaline phosphatase.
        J Clin Transl Hepatol. 2017; 5: 414-415
        • Rockey D.C.
        • Caldwell S.H.
        • Goodman Z.D.
        • Nelson R.C.
        • Smith A.D.
        American association for the study of liver D. Liver biopsy.
        Hepatology. 2009; 49: 1017-1044
        • Thursz M.R.
        • Richardson P.
        • Allison M.
        • et al.
        Prednisolone or pentoxifylline for alcoholic hepatitis.
        N Engl J Med. 2015; 372: 1619-1628
        • Kranzler H.R.
        • Soyka M.
        Diagnosis and pharmacotherapy of alcohol use disorder: a review.
        J Am Med Assoc. 2018; 320: 815-824
        • O'Connor E.A.
        • Perdue L.A.
        • Senger C.A.
        • et al.
        Screening and behavioral counseling interventions to reduce unhealthy alcohol use in adolescents and adults: updated evidence report and systematic review for the US preventive services task force.
        J Am Med Assoc. 2018; 320: 1910-1928
        • Mathurin P.
        • Lucey M.R.
        Liver transplantation in patients with alcohol-related liver disease: current status and future directions.
        Lancet Gastroenterol Hepatol. 2020; 5: 507-514
        • Wozniak M.K.
        • Wiergowski M.
        • Namiesnik J.
        • Biziuk M.
        Biomarkers of alcohol consumption in body fluids - possibilities and limitations of application in toxicological analysis.
        Curr Med Chem. 2019; 26: 177-196
        • Staufer K.
        • Andresen H.
        • Vettorazzi E.
        • Tobias N.
        • Nashan B.
        • Sterneck M.
        Urinary ethyl glucuronide as a novel screening tool in patients pre- and post-liver transplantation improves detection of alcohol consumption.
        Hepatology. 2011; 54: 1640-1649
      1. EASL Clinical Practice Guidelines on nutrition in chronic liver disease.
        J Hepatol. 2019; 70: 172-193
        • Fleming M.F.
        • Smith M.J.
        • Oslakovic E.
        • et al.
        Phosphatidylethanol detects moderate-to-heavy alcohol use in liver transplant recipients.
        Alcohol Clin Exp Res. 2017; 41: 857-862
        • Piano M.R.
        • Tiwari S.
        • Nevoral L.
        • Phillips S.A.
        Phosphatidylethanol levels are elevated and correlate strongly with AUDIT scores in young adult binge drinkers.
        Alcohol Alcohol. 2015; 50: 519-525
        • Simon T.W.
        Providing context for phosphatidylethanol as a biomarker of alcohol consumption with a pharmacokinetic model.
        Regul Toxicol Pharmacol. 2018; 94: 163-171
        • Russ K.B.
        • Chen N.W.
        • Kamath P.S.
        • Shah V.H.
        • Kuo Y.F.
        • Singal A.K.
        Alcohol use after liver transplantation is independent of liver disease etiology.
        Alcohol Alcohol. 2016; 51: 698-701
        • Jamal M.M.
        • Saadi Z.
        • Morgan T.R.
        Alcohol and hepatitis C.
        Dig Dis. 2005; 23: 285-296
        • Singal A.K.
        • Anand B.S.
        Mechanisms of synergy between alcohol and hepatitis C virus.
        J Clin Gastroenterol. 2007; 41: 761-772
        • Shoreibah M.
        • Anand B.S.
        • Singal A.K.
        Alcoholic hepatitis and concomitant hepatitis C virus infection.
        World J Gastroenterol. 2014; 20: 11929-11934
        • Singal A.K.
        • Kuo Y.F.
        • Anand B.S.
        Hepatitis C virus infection in alcoholic hepatitis: prevalence patterns and impact on in-hospital mortality.
        Eur J Gastroenterol Hepatol. 2012; 24: 1178-1184
        • Altamirano J.
        • Michelena J.
        Alcohol consumption as a cofactor for other liver diseases.
        Clin Liver Dis (Hoboken). 2013; 2: 72-75
        • Hamid R.F.
        • Forrest E.H.
        Is histology required for the diagnosis of alcoholic hepatitis? a review of published randomized controlled trials.
        Gut. 2011; 60 (A233-A233)
        • Elphick D.A.
        • Dube A.K.
        • McFarlane E.
        • Jones J.
        • Gleeson D.
        Spectrum of liver histology in presumed decompensated alcoholic liver disease.
        Am J Gastroenterol. 2007; 102: 780-788
        • Hamid R.
        • Forrest E.H.
        Is histology required for the diagnosis of alcoholic hepatitis? a review of published randomised controlled trials.
        Gut. 2011; 60
        • Forrest E.
        • Petts G.
        • Austin A.
        • et al.
        The diagnostic and prognostic significance of liver histology in alcoholic hepatitis.
        Aliment Pharmacol Ther. 2021; 53: 426-431
        • Roth N.C.
        • Saberi B.
        • Macklin J.
        • et al.
        Prediction of histologic alcoholic hepatitis based on clinical presentation limits the need for liver biopsy.
        Hepatol Commun. 2017; 1: 1070-1084
        • Hardy T.
        • Wells C.
        • Kendrick S.
        • et al.
        White cell count and platelet count associate with histological alcoholic hepatitis in jaundiced harmful drinkers.
        BMC Gastroenterol. 2013; 13: 55
        • Lucey M.R.
        • Mathurin P.
        • Morgan T.R.
        Alcoholic hepatitis.
        N Engl J Med. 2009; 360: 2758-2769
        • Greenwood S.M.
        • Leffler C.T.
        • Minkowitz S.
        The increased mortality rate of open liver biopsy in alcoholic hepatitis.
        Surg Gynecol Obstet. 1972; 134: 600-604
        • Kalambokis G.
        • Manousou P.
        • Vibhakorn S.
        • et al.
        Transjugular liver biopsy--indications, adequacy, quality of specimens, and complications--a systematic review.
        J Hepatol. 2007; 47: 284-294
        • Khurana S.
        • Butt W.
        • Khara H.S.
        • et al.
        Bi-lobar liver biopsy via EUS enhances the assessment of disease severity in patients with non-alcoholic steatohepatitis.
        Hepatol Int. 2019; 13: 323-329
        • Mohan B.P.
        • Shakhatreh M.
        • Garg R.
        • Ponnada S.
        • Adler D.G.
        Efficacy and safety of EUS-guided liver biopsy: a systematic review and meta-analysis.
        Gastrointest Endosc. 2019; 89 (e233): 238-246
        • Bhogal N.
        • Lamb B.
        • Arbeiter B.
        • et al.
        Safety and adequacy of endoscopic ultrasound-guided random liver biopsy in comparison with transjugular and percutaneous approaches.
        Endosc Int Open. 2020; 8: E1850-E1854
        • Arab J.P.
        • Roblero J.P.
        • Altamirano J.
        • et al.
        Alcohol-related liver disease: clinical practice guidelines by the Latin American association for the study of the liver (ALEH).
        Ann Hepatol. 2019; 18: 518-535
        • Altamirano J.
        • Miquel R.
        • Katoonizadeh A.
        • et al.
        A histologic scoring system for prognosis of patients with alcoholic hepatitis.
        Gastroenterology. 2014; 146 (e1231-1236): 1231-1239
        • Dubois M.
        • Sciarra A.
        • Trepo E.
        • et al.
        Histologic parameter score does not predict short-term survival in severe alcoholic hepatitis.
        United European Gastroenterol J. 2020; 8: 1003-1012
        • Horvath B.
        • Allende D.
        • Xie H.
        • et al.
        Interobserver variability in scoring liver biopsies with a diagnosis of alcoholic hepatitis.
        Alcohol Clin Exp Res. 2017; 41: 1568-1573
        • Shetty S.
        • Venkatakrishnan L.
        • Krishanveni J.
        • Kumari S.
        Transjugular liver biopsy in severe alcoholic hepatitis.
        Indian J Gastroenterol. 2017; 36: 23-26
        • Bird G.L.
        Investigation of alcoholic liver disease.
        Baillieres Clin Gastroenterol. 1993; 7: 663-682
        • Dhanda A.D.
        • Collins P.L.
        • McCune C.A.
        Is liver biopsy necessary in the management of alcoholic hepatitis?.
        World J Gastroenterol. 2013; 19: 7825-7829
        • Haiar J.
        • Singal A.K.
        Editorial: liver biopsy in alcoholic hepatitis-more clarity on when it may be needed.
        Aliment Pharmacol Ther. 2021; 53: 630-631
        • Lackner C.
        • Stauber R.E.
        • Davies S.
        • et al.
        Development and prognostic relevance of a histologic grading and staging system for alcohol-related liver disease.
        J Hepatol. Jun 11, 2021; (S0168-8278(21)00402-5)https://doi.org/10.1016/j.jhep.2021.05.029
        • Wells J.T.
        • Said A.
        • Agni R.
        • et al.
        The impact of acute alcoholic hepatitis in the explanted recipient liver on outcome after liver transplantation.
        Liver Transpl. 2007; 13: 1728-1735
        • Tome S.
        • Martinez-Rey C.
        • Gonzalez-Quintela A.
        • et al.
        Influence of superimposed alcoholic hepatitis on the outcome of liver transplantation for end-stage alcoholic liver disease.
        J Hepatol. 2002; 36: 793-798
        • Forrest EP G.
        • Austin A.
        • Lloyd K.
        • et al.
        The diagnostic and prognostic significance of liver histology in alcoholic hepatitis.
        Aliment Pharmacol Ther. 2020; 52 (Epub)
        • Michelena J.
        • Altamirano J.
        • Abraldes J.G.
        • et al.
        Systemic inflammatory response and serum lipopolysaccharide levels predict multiple organ failure and death in alcoholic hepatitis.
        Hepatology. 2015; 62: 762-772
        • Forrest E.H.
        • Evans C.D.
        • Stewart S.
        • et al.
        Analysis of factors predictive of mortality in alcoholic hepatitis and derivation and validation of the Glasgow alcoholic hepatitis score.
        Gut. 2005; 54: 1174-1179
        • Das S.
        • Maras J.S.
        • Hussain M.S.
        • et al.
        Hyperoxidized albumin modulates neutrophils to induce oxidative stress and inflammation in severe alcoholic hepatitis.
        Hepatology. 2017; 65: 631-646
        • Bukong T.N.
        • Cho Y.
        • Iracheta-Vellve A.
        • et al.
        Abnormal neutrophil traps and impaired efferocytosis contribute to liver injury and sepsis severity after binge alcohol use.
        J Hepatol. 2018; 69: 1145-1154
        • Taieb J.
        • Delarche C.
        • Paradis V.
        • et al.
        Polymorphonuclear neutrophils are a source of hepatocyte growth factor in patients with severe alcoholic hepatitis.
        J Hepatol. 2002; 36: 342-348
        • Dubois M.
        • Sciarra A.
        • Trépo E.
        • et al.
        Histologic parameter score does not predict short-term survival in severe alcoholic hepatitis.
        United European Gastroenterol J. 2020 Nov; 8 (2050640620949737): 1003-1012
        • Katoonizadeh A.
        • Laleman W.
        • Verslype C.
        • et al.
        Early features of acute-on-chronic alcoholic liver failure: a prospective cohort study.
        Gut. 2010; 59: 1561-1569
        • Shasthry S.M.
        • Rastogi A.
        • Bihari C.
        • et al.
        Histological activity score on baseline liver biopsy can predict non-response to steroids in patients with severe alcoholic hepatitis.
        Virchows Arch. 2018; 472: 667-675
        • Shabangu C.S.
        • Huang J.F.
        • Hsiao H.H.
        • Yu M.L.
        • Chuang W.L.
        • Wang S.C.
        Liquid biopsy for the diagnosis of viral hepatitis, fatty liver steatosis, and alcoholic liver diseases.
        Int J Mol Sci. 2020; 21
        • Singal A.K.
        • Bailey S.M.
        Cellular abnormalities and emerging biomarkers in alcohol-associated liver disease.
        Gene Expr. 2018; 19: 49-60
        • Verma V.K.
        • Li H.
        • Wang R.
        • et al.
        Alcohol stimulates macrophage activation through caspase-dependent hepatocyte derived release of CD40L containing extracellular vesicles.
        J Hepatol. 2016; 64: 651-660
        • Sehrawat T.S.
        • Arab J.P.
        • Liu M.
        • et al.
        Circulating extracellular vesicles carrying sphingolipid cargo for the diagnosis and dynamic risk profiling of alcoholic hepatitis.
        Hepatology. 2021; 73: 571-585
        • Atkinson S.R.
        • Grove J.I.
        • Liebig S.
        • et al.
        In severe alcoholic hepatitis, serum keratin-18 fragments are diagnostic, prognostic, and theragnostic biomarkers.
        Am J Gastroenterol. 2020; 115: 1857-1868
        • Perez-Hernandez O.
        • Gonzalez-Reimers E.
        • Quintero-Platt G.
        • et al.
        Malondialdehyde as a prognostic factor in alcoholic hepatitis.
        Alcohol Alcohol. 2017; 52: 305-310
        • Morales-Ibanez O.
        • Dominguez M.
        • Ki S.H.
        • et al.
        Human and experimental evidence supporting a role for osteopontin in alcoholic hepatitis.
        Hepatology. 2013; 58: 1742-1756
        • Affo S.
        • Morales-Ibanez O.
        • Rodrigo-Torres D.
        • et al.
        CCL20 mediates lipopolysaccharide induced liver injury and is a potential driver of inflammation and fibrosis in alcoholic hepatitis.
        Gut. 2014; 63: 1782-1792
        • Rachakonda V.
        • Gabbert C.
        • Raina A.
        • et al.
        Stratification of risk of death in severe acute alcoholic hepatitis using a panel of adipokines and cytokines.
        Alcohol Clin Exp Res. 2014; 38: 2712-2721
        • Puri P.
        • Liangpunsakul S.
        • Christensen J.E.
        • et al.
        The circulating microbiome signature and inferred functional metagenomics in alcoholic hepatitis.
        Hepatology (Baltimore, Md.). 2018; 67: 1284-1302
        • Hanouneh I.A.
        • Zein N.N.
        • Cikach F.
        • et al.
        The breathprints in patients with liver disease identify novel breath biomarkers in alcoholic hepatitis.
        Clin Gastroenterol Hepatol. 2014; 12: 516-523
        • Chacko B.K.
        • Kramer P.A.
        • Ravi S.
        • et al.
        The Bioenergetic Health Index: a new concept in mitochondrial translational research.
        Clin Sci (Lond). 2014; 127: 367-373
        • Salameh H.
        • Raff E.
        • Erwin A.
        • et al.
        PNPLA3 gene polymorphism is associated with predisposition to and severity of alcoholic liver disease.
        Am J Gastroenterol. 2015; 110: 846-856
        • Liangpunsakul S.
        • Beaudoin J.J.
        • Shah V.H.
        • et al.
        Interaction between the patatin-like phospholipase domain-containing protein 3 genotype and coffee drinking and the risk for acute alcoholic hepatitis.
        Hepatol Commun. 2018; 2: 29-34
        • Atkinson S.R.
        • Way M.J.
        • McQuillin A.
        • Morgan M.Y.
        • Thursz M.R.
        Homozygosity for rs738409:G in PNPLA3 is associated with increased mortality following an episode of severe alcoholic hepatitis.
        J Hepatol. 2017; 67: 120-127
        • Kirpich I.A.
        • Warner D.R.
        • Feng W.
        • et al.
        Mechanisms, biomarkers and targets for therapy in alcohol-associated liver injury: from Genetics to nutrition: summary of the ISBRA 2018 symposium.
        Alcohol (Fayetteville, N.Y.). 2020; 83: 105-114