De Ritis Ratio Calculator
Calculate the AST-to-ALT ratio from contemporaneous aminotransferase values.
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De Ritis ratio (AST/ALT)
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Auxiliary biochemical ratio; no liver-disease cause is assigned
About
The De Ritis ratio is serum aspartate aminotransferase (AST) divided by alanine aminotransferase (ALT). It is an auxiliary biochemical ratio that must be interpreted with the absolute enzyme activities, laboratory reference intervals, trends, and clinical context.
Formula
Interpretation
What the result represents: A unitless ratio between two aminotransferase activities measured in the same units.
Input units: AST and ALT in U/L from a reasonably contemporaneous laboratory panel.
Worked example: AST 40 U/L and ALT 20 U/L gives a ratio of 2.00.
Applicable population: Biochemical reference contexts in which both AST and ALT are available. Interpretation depends on whether either enzyme is elevated and on the applicable laboratory method and reference interval.
Interpretation limitations: A single threshold does not identify alcohol-associated liver disease, viral hepatitis, fibrosis, or another cause. Muscle injury, exercise, medicines, hemolysis, cardiac injury, sample quality, and laboratory methods can affect AST or ALT. Absolute values and the broader clinical evaluation remain essential.
FAQ
Disclaimer
Educational and informational reference only. Not intended to replace professional medical advice, diagnosis, treatment, or independent verification.