The ALT blood test is one of the usual tests done in a series of tests when liver disease is suspected.

ALT stands for “Alanine aminotransferase”, an enzyme important in liver function.

A high amount of ALT found in the blood is often an indicator of liver damage or inflammation. Even though the ALT test is considered to be a sensitive test for liver disease, high ALT levels in the blood can be caused by many different conditions, such as lead poisoning, drug reactions, shock, etc. For this reason, other testing is typically done in order to better interpret the ALT test.

The reason a high amount of ALT appears in damaged livers is because liver cells release this enzyme into the bloodstream when they are damaged. Although an abnormally high level of ALT in the bloodstream is greater in damaged livers, it may or may not correlate with the seriousness of the liver disease or predict what the outcome or course of the disease will be.

    Shaili’s ALT level: 783 **HIGH**
    Normal ALT range: (14-151 U/L)

What is the unit U/L?

    U/L is “Units per Liter”
    • A unit is an arbitrary amount agreed upon by scientists and doctors.
    • A liter is a measure of volume that is slightly larger than a quart.

References: “Symptoms and Diagnosis of Liver Disorders in Dogs” by Veterinary & Aquatic Services Dept., Drs. Foster & Smith web site;; Web MD; and