Explanation of Biomarker Ratios  Part 2 - ALT and AST Ratios

ALT and AST Ratios

ALT and AST are both enzymes that help convert amino acids into glucose. Assessing the ratio of the alanine aminotransferase (ALT) to aspartate aminotransferase enzyme (AST) provides us with metabolic clues. However, the ratios can also be confusing! This article, part 2 in our series on Biomarker Ratios, helps to answer some questions and make it easier to interpret the findings.

Detailed Insight into ALT and AST Ratios

ALT:AST Ratio

• What it Measures: The ALT ratio compares Alanine Aminotransferase (ALT) levels to Aspartate Aminotransferase (AST) in the blood.
• Significance: This ratio is primarily used to assess liver function and can help differentiate between various types of liver conditions.
• High ALT Ratio: Typically, a ratio greater than 1 indicates liver inflammation or damage. This is often seen in conditions like viral hepatitis or liver injury where ALT is more elevated than AST.
• Low ALT Ratio: A ratio less than 1 might suggest alcoholic liver disease or cirrhosis, where AST tends to be more elevated than ALT.

AST:ALT Ratio

• What it Measures: The AST ratio is simply the inverse of the ALT ratio, comparing AST levels to ALT levels.
• Significance: This ratio is also used to evaluate liver health and can provide similar insights but from a different perspective.
• High AST Ratio: A ratio greater than 1 suggests more significant liver fibrosis or cirrhosis. It's commonly elevated in alcoholic liver disease.
• Low AST Ratio: When this ratio is less than 1, it usually indicates less severe liver damage or early-stage liver disease, where ALT is more elevated than AST.

Common Questions and Confusions

Why Use Both Ratios?

1. Complementary Information: Using both ratios provides a comprehensive view of liver health. While they offer similar information, the emphasis on different enzymes can highlight specific conditions more clearly.
2. Diagnostic Precision: Some clinicians prefer one ratio over the other based on specific diagnostic criteria or the clinical context.

What if Both Ratios Are Normal?

1. Normal Ratios with Symptoms: If a patient has symptoms of liver disease but both ratios are normal, further investigation might be needed. This could include additional liver function tests or imaging studies.
2. Normal Ratios Without Symptoms: If there are no symptoms and both ratios are normal, this generally indicates healthy liver function. Regular monitoring might be sufficient.

Why Might Ratios Be Out of Range but Individual Levels Normal?

1. Early Detection: Ratios might indicate early signs of liver imbalance before individual enzyme levels become abnormal. This is crucial for preventive care.
2. Metabolic Interactions: The liver's complex metabolic processes mean that enzyme ratios can change due to various factors, including diet, medication, or other underlying conditions, even if individual levels appear normal.

Practical Examples

1. High ALT:AST Ratio (>1):
   1. Case: Patient presents with fatigue and jaundice.
   2. Interpretation: Likely liver inflammation, possibly due to hepatitis. Further tests like viral hepatitis panels might be warranted.
2. High AST:ALT Ratio (>1):
   1. Case: Patient has a history of heavy alcohol use.
   2. Interpretation: Suggestive of alcoholic liver disease or cirrhosis. Recommend further assessment through liver biopsy or imaging.
3. Confusing Scenario: Both ratios normal but symptoms persist.
   1. Case: Patient has mild abdominal pain and slight jaundice.
   2. Interpretation: Normal ratios might indicate early-stage liver disease. Recommend additional tests such as bilirubin levels, alkaline phosphatase, and imaging studies to rule out other causes.

Conclusion

Understanding the ALT and AST ratios is essential for accurate liver disease diagnosis and management. These ratios offer valuable insights that can complement individual biomarker levels, aiding in early detection and precise diagnosis of liver conditions. Properly interpreting these ratios helps in developing effective treatment plans and improving patient outcomes.

CLICK HERE to read part 1 in this series on Biomarker Ratios

Biomarker Ratios and the Optimal Platform

In Optimal, we calculate many of these biomarker ratios for you. Some are commonly found on a blood test (Albumin: globulin, LDL: HDL, etc.), but some are what we call "Functional Ratios." These would include the Free T3: Reverse T3 Ratio and sodium: Potassium Ratio, to name a few. In addition to ratios, we perform the HOMA2 calculations, QUICKI calculations, and Free Testosterone calculations as well!

While we calculate these ratios for you, we also give you, the user, the power to turn on or off any ratio or calculation automatically performed by Optimal.

Please CLICK HERE to watch an important video we made showing you exactly how to do this.

Lastly, we have a very robust CALCULATORS PAGE on this website. CLICK HERE to access all our calculators, which are free for you to use!