What exactly does aspartate aminotransferase refer to

In current clinical practice, aspartate aminotransferase is a medical test for liver function indicators, which can determine whether liver function is damaged. The normal value of aspartate aminotransferase in the liver of normal people is within the prescribed range. If it exceeds this normal range, it means that the person may be suffering from liver disease and needs to be diagnosed in time. Only in this way can we ensure that there will be no problems.

Classification

There are two isoenzymes of aspartate aminotransferase in the liver, which are present in liver cells and

The mitochondria (mAST) and cytoplasm (sAST) of cells. When liver cells are mildly affected, only sAST is released into the blood; when the affected cells are severe, mAST will also be released into the blood. Therefore, serum AST activity increases with the degree of liver cell damage.

In HBV-infected hepatitis and liver disease, if AST increases slightly with ALT, or if the increase is large but the duration is short, it may be mainly sAST, which has the same clinical significance as ALT. If AST increases more than ALT, although the increase is not too large but the duration is very long, it may be mainly mAST, indicating the chronicity and progression of the disease.

mechanism

Under normal circumstances, aspartate aminotransferase exists in tissue cells, with the highest content in myocardial cells, followed by the liver, and very little content in serum. Aspartate aminotransferase is mainly present in the mitochondria of liver cells. Only when the liver is severely necrotic or damaged can the concentration of aspartate aminotransferase in the serum be high. The aspartate aminotransferase level is high. The aminotransferase value of hepatitis patients is always high, reflecting that the inflammation of liver cells has never stopped, and the swelling, necrosis and other lesions of liver cells persist. Determining the level of this enzyme in serum can be used to assist in diagnosing diseases and observing recovery.

Normal value

The normal value of aspartate aminotransferase is 4-40U/L (unit per liter).

Due to the different reagents used in hospitals, the above normal values ​​are for reference only.

Detection Methods

Venous blood was obtained after fasting for 12 hours. That is to say, you should keep your stomach fasting and not eat for 12 hours before checking the aspartate aminotransferase, otherwise it will cause deviations in the test results.

Clinical symptoms

Clinically, if the course of hepatitis B is too long, the degree of chronicity is high, the liver cell parenchyma damage is severe, and the prognosis is poor, it is usually manifested as high aspartate aminotransferase, and the alanine aminotransferase/aspartate aminotransferase is less than 1.0. Patients with early liver cirrhosis and cirrhosis will also show elevated aspartate aminotransferase, with the alanine aminotransferase/aspartate aminotransferase ratio below 1.0. The clinical symptoms of high aspartate aminotransferase are also common symptoms of hepatitis, generally including low-grade fever, aversion to oil, nausea, vomiting, fatigue, poor appetite, and swollen and painful liver.

In short, if you find that your aspartate aminotransferase is high, don't be too nervous and don't worry that you have a serious liver disease, but you must pay enough attention to it, get enough rest, and receive regular review and treatment in a timely manner.

Liver function index

Aspartate aminotransferase is an important indicator in liver function tests. A high level indicates that the liver is damaged. Various viral hepatitis, cirrhosis, liver abscess, liver tuberculosis, liver cancer, fatty liver, alcoholic liver, etc. can all cause varying degrees of elevated transaminase levels. But it is not necessarily caused by the liver. Some drugs and diseases can also cause high transaminase levels. For example, myocardial infarction, pleurisy, and nephritis can all cause elevated aspartate aminotransferase levels.