What are the differences in Alanine Transaminase (ALT) and Aspartate Transaminase (AST) levels between alcoholic hepatitis and viral hepatitis?

From the Guidelines

ALT and AST levels can help distinguish between alcoholic and viral hepatitis, with an AST:ALT ratio greater than 1.5 typically indicating alcoholic hepatitis, as seen in a study published in Gastroenterology in 2016 1.

Key Findings

• In alcoholic hepatitis, the AST level is typically higher than ALT, with an AST:ALT ratio greater than 1.5, as stated in the study published in Gastroenterology in 2016 1.
• The AST elevation is usually moderate (2-6 times normal) while ALT is only mildly elevated, as reported in the study published in Hepatology in 2010 1.
• In contrast, viral hepatitis typically shows a higher ALT than AST, with an AST:ALT ratio less than 1, as mentioned in the study published in the Journal of Hepatology in 2012 1.

Diagnostic Considerations

• Other laboratory findings like elevated GGT and MCV in alcoholic hepatitis or the presence of viral markers in viral hepatitis provide additional diagnostic information, as noted in the study published in Gastroenterology in 2016 1.
• A liver biopsy can be useful in confirming the diagnosis and has prognostic value, as stated in the study published in Gastroenterology in 2016 1.
• The assessment of the severity of liver disease should include biochemical markers, including AST and ALT, as well as other tests such as hepatic ultrasound and HBV DNA detection, as recommended in the study published in the Journal of Hepatology in 2012 1.

Clinical Implications

• The diagnosis of alcoholic hepatitis is made by documentation of alcohol excess and evidence of liver disease, as reported in the study published in Hepatology in 2010 1.
• The presence of megamitochondria, satellitosis, and cholestasis may relate to prognosis, as noted in the study published in Gastroenterology in 2016 1.
• Patients with undiagnosed cirrhosis may decompensate owing to superimposed alcoholic hepatitis, as stated in the study published in Gastroenterology in 2016 1.

From the Research

ALT and AST in Alcoholic vs Viral Hepatitis

• The provided studies do not directly compare ALT and AST levels in alcoholic vs viral hepatitis 2, 3, 4, 5, 6.
• However, it is known that both alcoholic and viral hepatitis can cause elevations in liver enzymes, including ALT and AST 5.
• Alcoholic hepatitis is characterized by acute-onset jaundice and liver enzyme abnormalities in the setting of long-term heavy alcohol use 6.
• Viral hepatitis, on the other hand, is caused by viral infections such as hepatitis B and C, and can also lead to liver enzyme elevations 5.
• The diagnosis of alcoholic hepatitis is primarily clinical, based on a consensus definition from the National Institute on Alcohol Abuse and Alcoholism, and laboratory-based prognostic scores can help determine disease severity and treatment options 6.
• Treatment for alcoholic hepatitis primarily consists of supportive care, including alcohol cessation and nutritional support, while corticosteroids are recommended for severe cases 6.
• In contrast, the treatment for viral hepatitis often involves antiviral medications, and alcohol consumption can worsen viral liver disease 5.

Key Differences

• The etiology of alcoholic and viral hepatitis differs, with alcoholic hepatitis caused by long-term heavy alcohol use and viral hepatitis caused by viral infections 3, 5.
• The clinical presentation and diagnosis of alcoholic and viral hepatitis may also differ, with alcoholic hepatitis often characterized by acute-onset jaundice and liver enzyme abnormalities, and viral hepatitis often diagnosed through laboratory tests and imaging studies 6, 5.
• The treatment and management of alcoholic and viral hepatitis also differ, with alcoholic hepatitis often requiring supportive care and corticosteroids, and viral hepatitis often requiring antiviral medications 6, 5.