The examination of alanine aminotransferase, also known as ALT or TGP, is a blood test that helps identify liver lesions and diseases because of the elevated presence of the enzyme alanine aminotransferase, also called glutamic pyruvic transaminase in the blood, which is normally found between 7 and 56 U / L of blood.
The enzyme pyruvic transaminase is present inside the cells of the liver and, therefore, when there is some injury in this organ, caused by a virus or toxic substances, for example, it is common that the enzyme is released into the bloodstream, leading to an increase of your blood test levels, which can mean:
ALT too high
- 10 times higher than normal: usually a change caused by acute hepatitis caused by viruses or use of some medicines. See other causes of acute hepatitis.
- 100 times higher than normal: it is very common in users of drugs, alcohol or other substances that cause serious damage to the liver.
High ALT
- 4 times higher than normal: it may be a sign of chronic hepatitis and, therefore, may indicate liver disease such as cirrhosis or cancer, for example.
Although it is a very specific marker for liver damage, this enzyme can also be found in the muscles and heart in smaller amounts, and an increase in the concentration of this enzyme in the blood can be observed after intense physical exercises, for example. Therefore, in order to evaluate the functioning and identify lesions in the liver, the physician may request the dosing of other enzymes, such as lactate dehydrogenase (LDH) and AST or TGO. Learn more about the AST exam.
What to do in case of high ALT
In cases in which the pyruvate transaminase test is of high value, it is recommended to consult a hepatologist to make an assessment of the person's clinical history and to identify the cause of the change in the liver. The doctor may also order more specific tests such as hepatitis tests or liver biopsy to confirm the diagnostic hypothesis.
In addition, in cases of elevated ALT it is also advisable to make a proper diet for the liver, low in fat and giving preference to cooked food. Learn how to diet for the liver.
When to take the ALT exam
The alanine aminotransferase test is used to detect liver damage and therefore may be recommended for people who have:
- Fat in the liver or are overweight;
- Excessive tiredness;
- Loss of appetite;
- Nausea and vomiting;
- Swelling of the belly;
- Dark urine;
- Skin and yellow eyes.
However, ALT levels may already be high even when the patient does not have any symptoms, and is a great tool to diagnose liver problems early. In this way, the ALT test can also be done when there is a history of exposure to the hepatitis virus, excessive use of alcoholic beverages, or the presence of diabetes. Find out what other changes in the blood test mean.
