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Question about AST, ALT, and their relationship to the AST:ALT ratio

I have a client that has had improved Liver biomarkers - ALT and AST. However, the AST: ALT ratio has altered to say the ratio is now out of range when before it was in range. Can you explain this?

We would need to know if the enzymes are within the lab or optimal range even if they are improved.
Also, we would need to know which direction the AST:ALT (De Ritis) ratio is going in, is it increasing or decreasing?

An alteration in the ratio is not diagnostic of disease and further assessments must be made since ALT and AST are found in other tissues besides the liver.

The De Ritis ratio is especially useful for monitoring known chronic liver disease including NAFLD, chronic alcoholism, and chronic viral hepatitis. In such cases, an increasing AST:ALT ratio over time suggests the presence of cirrhosis, fibrosis, or other long-term complications.

  • In healthy adults, a De Ritis ratio of 1 to less than 1.7 in women and 1 to less than 1.3 in men may be unremarkable (Botros 2013).
  • AST: ALT may be elevated over 1 in the event of muscle damage/breakdown, especially in the event of an isolated elevation in AST.
  • Intense exercise can lead to an acute increase in AST so getting a full history and monitoring biomarkers over time is always recommended.
  • An elevation greater than 1 can be seen with Wilson’s disease, cirrhosis, and biliary obstruction.
  • A level between 1 and 1.5 may reflect resolving hepatitis.
  • A level of greater than 2 may be suggestive of alcoholic liver disease, drug-induced hepatic damage, or malignancy such as esophageal cancer.
  • Depletion of cofactor vitamin B6 (pyridoxal phosphate) can alter enzymes levels and activity so be sure to complete that full assessment.


Botros, Mona, and Kenneth A Sikaris. “The de ritis ratio: the test of time.” The Clinical biochemist. Reviews vol. 34,3 (2013): 117-30.

Gowda S, Desai PB, Hull VV, et al. A review on laboratory liver function tests. Pan Afr Med J. 2009 Nov 22;3:17.

Hall P, Cash J. What is the real function of the liver 'function' tests? Ulster Med J. 2012 Jan;81(1):30-6.

Rief P, Pichler M, Raggam R, et al. The AST/ALT (De-Ritis) ratio: A novel marker for critical limb ischemia in peripheral arterial occlusive disease patients. Medicine (Baltimore). 2016 Jun;95(24):e3843.

Thapa BR, Walia A. Liver function tests and their interpretation. Indian J Pediatr. 2007 Jul;74(7):663-71. Review. PubMed PMID: 17699976.

Woreta TA, Alqahtani SA. Evaluation of abnormal liver tests. Med Clin North Am. 2014 Jan;98(1):1-16.