What is it?

Alanine Aminotransferase (ALT) is an enzyme produced by the liver. It is used as a marker of liver function/damage and high levels of ALT may be an indicator that the liver has been damaged.

This marker should be interpreted together with another liver enzyme, the Aspartate Aminotransferase (AST) which will give a more complete overall picture of the enzymes.

Reference ranges

If your indicative ALT level is lower than the reference range for our laboratory:

Having a lower than normal ALT result is uncommon and usually is not a cause for concern. Occasionally it could indicate a vitamin B6 deficiency or kidney disease.

Please discuss this result with your GP.

If your indicative ALT level is higher than the reference range for our laboratory:

Extremely high concentrations of ALT are often due to hepatitis and viral infection. The levels will, eventually (sometimes t may take up to 3 months) return to normal.

High levels of ALT concentrations are present in chronic hepatitis and vary between normal and elevated levels, so it is worth performing this test frequently to monitor results over time.

Alcohol and diabetes may lead to a moderately high level of ALT, causing increased fat levels of the liver.

Please discuss this result with your GP.