What can increase AST?

Study liver anatomy and function with our medical students test. Engage with detailed multiple choice questions, each with hints and explanations. Prepare effectively for your test!

AST is an enzyme found in tissues rich in it, especially the liver and heart. When these tissues are damaged, AST leaks into the bloodstream. Therefore, elevations occur with hepatocellular injury (liver disease) and with myocardial infarction (heart muscle damage). AST is not specific to the liver alone, so seeing an increase can point to injury in either the liver or the heart. Dehydration or hypothyroidism don’t typically cause a notable AST rise, whereas viral infection can affect the liver but generally doesn’t explain the level of AST rise you’d expect from clear tissue injury in liver or heart. That’s why the option describing both hepatocellular pathology and myocardial infarction best explains an increased AST.