Does alcohol hepatitis cause elevated liver function tests (LFTs)?

Does Alcoholic Hepatitis Cause Elevated LFTs?

Yes, alcoholic hepatitis definitively causes elevated liver function tests (LFTs), though the pattern and degree of elevation are characteristic and diagnostically important. 1, 2

Characteristic LFT Pattern in Alcoholic Hepatitis

The hallmark finding is an AST/ALT ratio greater than 2:1, which occurs in over 98% of histologically proven alcoholic hepatitis cases. 2 This distinctive pattern helps differentiate alcoholic liver disease from other causes of hepatic injury:

• AST is typically elevated 2-6 times the upper limit of normal 1, 3
• ALT levels rarely exceed 200 IU/L in alcoholic hepatitis 1, 2
• AST and ALT typically do not exceed 400 IU/mL, which distinguishes alcoholic hepatitis from acute drug-induced liver injury or ischemic hepatitis 2
• Ratios exceeding 3:1 are highly specific for alcoholic liver disease 1, 2

The mechanism behind this pattern involves alcohol-induced mitochondrial damage, which causes preferential release of AST compared to ALT. 1

Additional LFT Abnormalities

Beyond transaminases, alcoholic hepatitis produces other characteristic laboratory findings:

• GGT elevation is present in 75% of habitual drinkers, though specificity decreases in advanced disease 1
• The combination of AST predominance with elevated GGT strongly suggests chronic alcohol consumption 1
• Elevated bilirubin and prolonged INR indicate more severe disease and worse prognosis 2, 4
• Alkaline phosphatase may be elevated, reflecting cholestatic injury 4

Critical Clinical Caveat: Normal LFTs Don't Exclude Disease

A major pitfall is that normal or near-normal aminotransferases are common in alcoholic cirrhosis and do not exclude advanced liver disease. 5 In one cohort of 78 patients with documented alcoholic cirrhosis:

• 90% had normal ALT levels 5
• 15% had normal AST levels 5
• Aminotransferase levels bore no relationship to clinical events, complications, or mortality 5
• Normal transaminases do not exclude cirrhosis, as ALT can be normal in over 50% of patients with advanced fibrosis 2

This occurs because burned-out cirrhotic livers have reduced hepatocyte mass and therefore less capacity to release transaminases. 5

Diagnostic Approach When LFTs Are Elevated

When evaluating suspected alcoholic hepatitis with elevated LFTs:

1. Calculate the AST/ALT ratio - values >1.5 suggest alcoholic etiology, >2 strongly suggest it, and >3 are highly specific 1, 2

2. Assess severity using prognostic scores - Maddrey Discriminant Function ≥32 indicates severe disease requiring corticosteroid consideration 2, 6

3. Obtain comprehensive hepatic panel including total bilirubin, albumin, INR, and GGT to assess synthetic function 2

4. Perform non-invasive fibrosis assessment - FibroScan >12-15 kPa suggests advanced fibrosis, and FIB-4 score helps stratify risk even when transaminases are normal 2

5. Rule out alternative diagnoses - AST/ALT >400 IU/mL should prompt consideration of drug-induced liver injury or ischemic hepatitis rather than alcoholic hepatitis alone 2

Important Clinical Considerations

Inflammation and cholestasis in acute alcoholic hepatitis can falsely elevate liver stiffness measurements beyond what fibrosis alone would cause, so interpret transient elastography cautiously when AST >100 U/L. 7

Abstinence from alcohol typically leads to improvement in liver enzymes over time in early alcoholic liver disease, making alcohol cessation the cornerstone of management. 3