What is ALT, SGPT?
Alanine Transaminase (ALT) test is also known as Alanine aminotransferase test, Serum Glutamic-Pyruvate Transaminase, SGPT, and GPT. This test measures the levels of ALT in the blood. Alanine Transaminase is an enzyme which is found in the cells of the liver and kidney. It is done to screen any possible damage done to the liver. It basically checks the proper functioning of the liver.
Why is ALT, SGPT done?
As a part of the liver function test
To detect hepatitis
To detect damage to the liver due to drugs or substances toxic to the liver
In case of signs or symptoms of liver disease like dark colored urine, loss of appetite, nausea, vomiting, jaundice, and abdominal pain
In case of increased risk of developing a liver disease like heavy drinking, exposure to hepatitis virus, or having a family history of liver disease
What does ALT, SGPT Measure?
Alanine Transaminase test measures the levels of alanine transaminase in the blood. Alanine Transaminase is an enzyme which is found in liver and kidney cells. However, this enzyme, in less quantity, can be found in the muscles and the heart. Its function is to convert alanine (an amino acid found in proteins) to pyruvate (intermediate in cellular energy production).
Generally, these levels of alanine transaminase in the blood remain low in healthy individuals. However, if there is any damage to the liver, alanine transaminase is released in the blood. This process helps in early detection of any damage to the liver.
The function of the liver is to process the nutrients of the body. It also produces bile which helps in digesting fats along with the production of other important proteins such as blood clotting factors and albumin. The liver breaks the potentially toxic substances into harmless products which can be used or eliminated by the body.
This test is done with another liver enzyme, aspartate aminotransferase (AST) as a part of the liver panel. In case of damage to the liver, there is a sudden rise in levels of both enzymes. However, alanine transaminase is more specific for the liver. In some cases, it is possible that only one of them is increased. The AST/ALT ratio can be calculated to differentiate between various causes and severity of the liver injury. This can also help to distinguish whether the injury is from damage to the liver or heart or muscles.
Interpreting ALT, SGPT results
ALT (SGPT), Serum < 50 U/L
Reference range may vary from lab to lab*
Very high ALT levels (more than 10 times normal) are usually due to acute hepatitis which is generally caused due to a viral infection
High ALT levels (four times normal) may be seen in chronic hepatitis, obstruction of bile ducts, or cirrhosis
In most liver diseases, the ALT level is higher than AST and the AST/ALT ratio will be low (less than 1). The AST/ALT ratio is greater than 1 in alcoholic hepatitis, cirrhosis, heart or muscle injury
ALT is more specific than AST for liver disease