What is a Liver Cleanse?

The purpose of liver function tests is to detect the presence or absence of liver disease, the degree of liver damage, identify the cause of liver disease, determine the prognosis, and identify the cause of jaundice. At present, there are many types of clinical trials of liver function, no less than dozens, but each type of liver function test can only explore a certain aspect of the liver function. Until now, there is no test that can reflect the liver function. All functions. Therefore, in order to obtain a more objective conclusion of liver function, multiple combinations of liver function tests should be selected and rechecked if necessary. At the same time, when evaluating the results of liver function tests, liver function must be comprehensively considered in combination with clinical symptoms to avoid one-sidedness and subjectivity. Due to the differences in laboratory conditions, operators, and testing methods at each hospital, the reference ranges for normal values of liver function tests provided by different hospitals are generally different.

Basic Information

English name

liver function

Visiting department

Laboratory, Gastroenterology

Common locations

liver

Common causes

Liver Disease

Hepatic function reflects liver cell damage

Serum enzyme detection is commonly used, including alanine aminotransferase (also known as alanine aminotransferase, ALT), aspartate aminotransferase (also known as aspartate aminotransferase, AST), alkaline phosphatase (ALP), -glutamate Aminoacyl transpeptidase (-GT or GGT), etc. In various enzyme tests, ALT and AST can sensitively reflect the degree of damage to liver cells. When acute liver damage is caused by various acute viral hepatitis, drugs, or alcohol, serum ALT is most sensitive. ALT increases sharply before clinical symptoms such as jaundice, and AST also increases, but the level of AST is not as high as ALT. In chronic hepatitis and cirrhosis, AST rises more than ALT, so AST mainly reflects the degree of liver damage.

In severe hepatitis, due to a large number of hepatocyte necrosis, ALT in the blood gradually decreases, but at this time, bilirubin gradually increases, that is, the phenomenon of "bile enzyme separation" occurs, which is often a precursor of liver necrosis. During the recovery of acute hepatitis, if ALT is normal and -GT continues to rise, chronic hepatitis is often indicated. If -GT continues to exceed the normal reference value when suffering from chronic hepatitis, it indicates that chronic hepatitis is active.

Items that reflect liver secretion and excretion

Including the determination of total bilirubin (TBil), direct bilirubin (DBil), total bile acid (TBA), etc. Elevated total bilirubin can occur in patients with viral hepatitis, toxic hepatitis caused by drugs or alcohol, hemolytic jaundice, pernicious anemia, paroxysmal hemoglobinuria, neonatal jaundice, and internal bleeding. Direct bilirubin refers to the part of total bilirubin bound to the glucuronide group after liver treatment. Direct elevation of bilirubin indicates that the excretion of hepatocytes after processing bilirubin is impaired, that is, biliary obstruction occurs. If TBil and DBil are measured at the same time, the diagnosis of hemolytic, hepatocellular and obstructive jaundice can be differentiated. Hemolytic jaundice: general TBil <85mol / L, direct bilirubin / total bilirubin <20%; hepatocellular jaundice: general TBil <200mol / L, direct bilirubin / total bilirubin> 35%; obstruction Jaundice: Generally TBil> 340mol / L, direct bilirubin / total bilirubin> 60%.

In addition, -GT, ALP, and 5'-nucleotide (5'-NT) are also very sensitive enzymes that reflect cholestasis. Their elevation mainly indicates that there may be diseases related to biliary obstruction.

Hepatic function reflects the synthetic reserve function of the liver

Including prealbumin (PA), albumin (Alb), cholinesterase (CHE), and prothrombin time (PT). They are routine tests that reflect the reserve capacity of liver by measuring its synthetic function. Decreased prealbumin and albumin indicate a weakened ability of the liver to synthesize proteins. When suffering from various liver diseases, the heavier the disease, the lower the serum cholinesterase activity. If cholinesterase activity continues to decrease and shows no signs of recovery, it is more likely to indicate a poor prognosis. ALT and GGT are elevated in hepatobiliary diseases. If CHE decreases at the same time, it is liver disease, while normal people are mostly biliary disease. In addition, CHE increase can be seen in hyperthyroidism, diabetes, nephrotic syndrome and fatty liver.

Prolonged prothrombin time (PT) reveals a decrease in the liver's ability to synthesize various coagulation factors.

Items that reflect liver fibrosis and cirrhosis

Including albumin (Alb), total bilirubin (TBil), monoamine oxidase (MAO), serum protein electrophoresis, etc. When patients have liver fibrosis or cirrhosis, they will experience a decrease in serum albumin and total bilirubin, accompanied by an increase in monoamine oxidase. The increase of gamma globulin in serum protein electrophoresis can evaluate the evolution and prognosis of chronic liver disease, suggesting that liver macrophages (Kupffer cells) have reduced function and cannot remove endogenous or enteric antigen substances in the blood circulation.

In addition, hyaluronic acid (HA), laminin (LN), type III procollagen peptide, and type IV collagen have been used more clinically in recent years. Determining their serum levels can reflect changes in liver endothelial cells, fat storage cells, and fibroblasts. If their serum levels increase, it often indicates that patients may have liver fibrosis and cirrhosis.

Liver function reflects serum markers of liver tumors

The only biochemical test that can be used to diagnose primary liver cancer is alpha-fetoprotein (AFP). Alpha-fetoprotein was originally used for the early diagnosis of liver cancer. It has increased 8 months before the symptoms of liver cancer patients. At this time, most patients with liver cancer have no obvious symptoms. After surgery, the prognosis of these patients is significantly improved. Alpha-fetoprotein is also widely used to monitor the efficacy of liver cancer surgery, follow-up after surgery, and follow-up of high-risk populations. However, in normal pregnant women, a small number of hepatitis and cirrhosis, gonad malignant tumors, alpha fetoprotein will also increase, but the increase is not as high as that of primary liver cancer. In addition, some patients with liver cancer have normal alpha-fetoprotein values, so imaging studies such as B-mode, CT, magnetic resonance (MRI), and hepatic angiography should be performed at the same time to increase the reliability of the diagnosis.

It is worth mentioning that -L-fucosidase (AFU), the positive rate of serum AFU measurement for the diagnosis of primary liver cancer is between 64% and 84%, and the specificity is about 90%. AFU is more and more recognized as the diagnosis, follow-up and cirrhosis of liver cancer due to its high sensitivity for detecting small liver cancer, its high specificity for predicting liver cirrhosis complicated with liver cancer, and its good complementarity with AFP measurement Indispensable means of guardianship. In addition, the determination of serum AFU activity has some overlap between certain metastatic liver cancer, lung cancer, breast cancer, ovarian or uterine cancer, and even some non-tumor diseases such as cirrhosis, chronic hepatitis and gastrointestinal bleeding have slightly increased. High, so pay attention to identification.

In addition, in patients with liver tumors, -GT, ALP, leucine aminotranspeptidase (LAP), 5'-NT, etc. also often increase.