De Ritis Ratio Calculator (AST/ALT)
Calculate the AST/ALT ratio to differentiate between liver disease causes. Differentiate alcoholic liver disease from viral hepatitis with this hepatology tool.
About
The De Ritis Ratio is a derived metric obtained by dividing the serum Aspartate Transaminase (AST) level by the Alanine Transaminase (ALT) level. Hepatologists utilize this ratio to narrow down the etiology of liver injury when enzyme levels are elevated. In healthy individuals the ratio typically hovers just below 1.0. However specific pathologies alter the clearance and release rates of these enzymes differently. For instance alcoholic damage selectively depletes mitochondrial AST less than cytosolic ALT causing the ratio to spike. Conversely viral hepatitis typically causes a greater rise in ALT leading to a lower ratio. This tool aids in distinguishing alcoholic liver disease from non-alcoholic fatty liver disease (NAFLD) and acute viral infections.
Formulas
The calculation is a simple division of two enzyme concentration values.
Both values must be measured in the same units (usually IU/L) for the ratio to be valid.
Reference Data
| De Ritis Ratio | Likely Pathology | Mechanism | Typical AST/ALT Levels |
|---|---|---|---|
| > 2.0 | Alcoholic Liver Disease | B6 deficiency lowers ALT synthesis | AST < 500 IU/L |
| > 1.5 | Cirrhosis (Advanced) | Fibrosis alters enzyme clearance | Variable |
| 1.0 − 2.0 | Normal / Heart Disease | Muscle damage releases AST | Normal or Slightly High |
| < 1.0 | Viral Hepatitis (Acute) | Cytosolic leak favors ALT | Very High (> 1000) |
| < 1.0 | NAFLD / NASH | Insulin resistance pattern | Mild Elevation |
| < 1.0 | Cholestasis | Obstructive pattern | ALP also elevated |
| > 3.0 | Wilson's Disease | Hemolysis releases AST | Acute presentation |
| NaN | Invalid Data | Division by zero | ALT = 0 |