Enter the ALT and LDH values into the calculator to determine the ALT/LDH ratio.

ALT/LDH Ratio Calculator

ALT/LDH Ratio AST/ALT Ratio

Enter ALT and LDH to calculate the ALT/LDH ratio.

Note: For these enzymes, U/L and IU/L are typically equivalent on lab reports; this calculator treats them as the same.

ALT/LDH pattern information
Important: This calculator is for educational information only and is not medical advice or a diagnosis. ALT, AST, and LDH are markers of tissue injury and can rise from liver and non-liver causes; liver “function” is often assessed using tests such as bilirubin, INR/prothrombin time, and albumin (along with symptoms and exam findings). Ratios are not validated as stand-alone diagnostic tests—clinicians interpret them with your history (including medications such as acetaminophen), alcohol use, hepatitis risk, and other labs. Seek urgent medical care for jaundice, confusion, fainting, severe abdominal pain, vomiting blood, black stools, or suspected overdose.
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ALT/LDH Ratio Formula

The following formula is used to calculate the ALT/LDH ratio for given ALT and LDH values.

R = \frac{ALT}{LDH}

Variables:

  • R is the ALT/LDH ratio
  • ALT is the alanine aminotransferase level in U/L
  • LDH is the lactate dehydrogenase level in U/L

To calculate the ALT/LDH ratio, divide the ALT value by the LDH value.

What is ALT/LDH Ratio?

The ALT/LDH ratio is a simple metric used to help describe patterns of enzyme elevation that may occur with liver injury and many other conditions. ALT (alanine aminotransferase) and LDH (lactate dehydrogenase) are enzymes found in the liver and other tissues, and elevated blood levels generally reflect tissue injury rather than liver functional capacity. ALT/AST/LDH do not measure liver function by themselves; bilirubin, INR/prothrombin time, albumin, and clinical findings are often needed to assess liver function.

How to Calculate ALT/LDH Ratio?

The following steps outline how to calculate the ALT/LDH ratio.

  1. First, obtain the ALT value in U/L.
  2. Next, obtain the LDH value in U/L.
  3. Finally, calculate the ALT/LDH ratio using the formula R = ALT / LDH.
  4. After inserting the values and calculating the result, check your answer with the calculator above.

Example Problem : 

Use the following variables as an example problem to test your knowledge.

ALT (U/L) = 45

LDH (U/L) = 150

ALT/LDH Ratio = 45 / 150 = 0.3