Biomarkers in Alcoholic Liver Disease
Year: 2025
Type: article
Abstract: Chronic alcohol consumption leads to oxidative stress and inflammation within the liver. Alcohol metabolism by alcohol dehydrogenase and microsomal ethanol oxidizing system generates toxic metabolites (e.g., acetaldehyde), triggering hepatocellular injury. Repetitive injury cycles may progress from fatty change (steatosis) to steatohepatitis, eventually resulting in fibrosis and cirrhosis. Biomarkers serve as early detection of subclinical liver damage,distinguishing alcoholic from non-alcoholic causes and monitoring disease progression and response to therapy. There are some conventional biomarkers used to diagnose alcoholic liver disease. Among them aspartate aminotransferase (AST) and alanine aminotransferase (ALT) ratio play a crucial role for diagnosis. Acute liver disease (ALD) classically presents with an AST to ALT ratio of ≥2:1. Mechanism lies behind it is Alcohol-induced deficiency of pyridoxine (vitamin B6) leads to low ALT, while mitochondrial damage elevates AST preferentially. It is an useful clue but not entirely specific. Absolute transaminase levels typically remain <300 IU/L in ALD. Higher levels suggest an alternate or additional acute hepatic insult. Another biomarker is gamma-glutamyl transferase (GGT). Chronic alcohol exposure upregulates GGT enzymes, sensitive to biliary epithelial and hepatocyte injury. It is elevated in ALD but lacks specificity, useful with other markers or suspicion of ongoing alcohol intake. Mean corpuscular volume (MCV) is an indirect marker. Alcohol’s toxic effects and folate deficiency cause macrocytosis. It is elevated in 50%–80% of chronic heavy alcohol users. MCV may normalize with sustained abstinence. Serum bilirubin I s also important for liver function assessment. Both conjugated and unconjugated bilirubin levels may rise. Hyperbilirubinemia correlates with severity. Sustained elevated bilirubin indicates poor prognosis. Prothrombin time (PT)/international normalized ratio (INR) reflects hepatic synthetic capacity. Prolonged PT/INR distinguishes mild from severe ALD. It guides therapy decisions. There are some emerging and additional biomarkers used now-a-days, among them Cytokeratin-18 (CK-18) and Its Fragments plays a vital role. It reflects hepatocyte apoptosis and necrosis, may predict severity in alcoholic hepatitis (ongoing validation). Chronic inflammation drives ALD progression. Inflammatory Mediators (e.g., TNF-α, IL-6) play a vital role to assess the progression. They have potential role in guiding targeted therapies (not yet standard practice). Fibrosis Markers (e.g., Hyaluronic Acid, Procollagen III Peptide) are the noninvasive fibrosis panels, helps to assist in staging of fibrosis. It reduces the need for repeated liver biopsies. Diagnostic strategies incorporating biomarkers are followed in ALD patient’s management. So initial screening starts with comprehensive metabolic panel, CBC, coagulation profile, and liver enzymes followed by calculating AST/ALT ratio, note MCV, assess GGT. After that alcohol use screening (clinical history, CAGE or AUDIT questionnaires), serum CDT if indicated, have to be done. Imaging studies are useful to exclude other pathologies. There are some prognostic scoring systems are used like Maddrey’s discriminant function (DF): DF = 4.6 × [PT (in seconds) − Control PT] + total bilirubin (mg/dL). Score ≥32 suggests severe disease. Another is model for end-stage liver disease Score which incorporates creatinine, bilirubin, and INR for transplant prioritization. Last is the liver biopsy which is seldomly done now-a-days. It is indicated in certain scenarios. Histopathology findings reveal Mallory bodies, neutrophilic infiltration, pericentral fibrosis. Finally for clinical management and monitoring we have to determine disease severity by high bilirubin, elevated PT/INR, and low albumin indicate advanced dysfunction. Corticosteroids or pentoxifylline considered in severe cases when Maddrey’s DF ≥ 32. For ongoing assessment abstinence from Alcohol should be the Primary intervention. Therefore overall disease progress is tracked via biomarkers (e.g., GGT, CDT). Another concern is Nutritional support which is done by Protein supplementation, vitamin correction. MCV, RBC folate, and LFTs to be monitored regularly, specifically periodic AST, ALT, GGT, bilirubin, and INR assessments. Also imaging surveillance for cirrhosis complications is also important for follow-up. Now for future prospects some Novel biomarkers like microRNAs are under investigation. Recently there is growing acceptance of noninvasive fibrosis markers for easy assessment and patient’s compliance. As to conclude, biomarkers are vital for diagnosing, staging, and managing alcoholic liver disease. Traditional markers like AST (with its characteristic ALT ratio), GGT, bilirubin, PT/INR, and MCV are routinely employed. Emerging markers hold promise for enhancing prognostication and early detection. Integrating biomarkers with comprehensive clinical evaluation, alcohol cessation, and supportive measures tailored to liver injury severity forms the cornerstone of ALD management. Strategies must be individualized, considering disease severity, comorbidities, and patient adherence. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.
Author: Sreemanta Madhab Baruah
Institution: Assam Medical College
Language: English
Subfield: Pathology and Forensic Medicine
Field: Medicine
Domain: Health Sciences
Open Access status: diamond
OpenAlex ID: W4411624918