total bile acids

The production and metabolism of bile acids are closely related to the liver. Serum bile acid levels are an important indicator of liver parenchymal damage. Determination of serum total bile acid (TBA) is of great value in the diagnosis of liver disease. In patients with acute hepatitis, serum TBA is reduced from the initial high value to the normal level at the same time as AST. If it does not continue to rise or rises, it may develop chronically. Basic Information Specialist classification: Digestive examination classification: biochemical examination Applicable gender: whether men and women apply fasting: fasting Tips: Do not eat too greasy, high-protein foods the day before the blood draw, avoid heavy drinking. The alcohol content in the blood directly affects the test results. Normal value Fasting, adult serum 1 ~ 7μmol / L (3.5 ± 1.75). Clinical significance 1, acute hepatitis: serum TBA increased significantly in acute hepatitis, up to 10 to 100 times the level of normal people, or even higher. 2. Chronic hepatitis: F-TBA and P-TBA of chronic active hepatitis were significantly higher than chronic persistent hepatitis. Therefore, serum TBA determination is important for the identification of chronic hepatitis and monitoring the prognosis and therapeutic effect of chronic active hepatitis. 3, cirrhosis: liver cirrhosis, liver metabolism of bile acid is reduced, serum TBA increased in different stages of cirrhosis, the increase is generally higher than chronic active hepatitis, even in the late stage of cirrhosis. When liver disease activity was minimized, indicators such as bilirubin, transaminase and alkaline phosphatase turned normal, but serum TBA remained at a high level. 4, alcoholic liver disease: ethanolic liver disease serum TBA can be increased. When severe liver injury occurs in alcoholic liver disease (including cirrhosis), serum TBA is significantly increased, while mild to moderate injury is not obvious. 5, toxic liver disease: serum TBA determination of toxic liver disease diagnosis is better than conventional liver function test. Acute liver injury caused by liver poisoning caused by taking certain therapeutic drugs in the clinic is also diagnostic. 6, cholestasis: serum TBA determination has a higher sensitivity and specificity for the diagnosis of cholestasis. Extrahepatic bile duct obstruction and intrahepatic cholestasis including acute hepatitis, initial biliary cirrhosis, neonatal cholestasis, and gestational cholestasis can cause an increase in TBA. In the early stages of biliary obstruction, bile secretion is reduced, resulting in a significant increase in serum TBA, and remains almost unchanged at different stages of occlusion; serum bilirubin levels vary with different stages. The bile acid content in the liver tissue of patients with cholestasis was significantly higher than that of normal people. The CA increased 8 times, the CDCA increased 4 times, and the DCA increased only 1.5%. After the extrahepatic obstruction was relieved by drainage, serum TBA levels decreased rapidly, while other indicators slowly returned to normal. In all liver diseases, postprandial serum TBA levels and abnormal rates were higher than those on fasting, so the postprandial TBA measurement for liver disease was more sensitive than the fasting test. It has been reported that the sensitivity and specificity of TBA for the diagnosis of various liver diseases after meals are as high as 100%, while 40% of patients with fasting serum TBA are also in the normal range. Whether acute hepatitis is chronic, continuous monitoring of postprandial TBA levels can be observed in chronic processes. Whether liver fibrosis changes in chronic active hepatitis, continuous monitoring after meals can also understand the degree of fibrosis, and liver injury can be obtained without liver biopsy. High results may be diseases: duodenogastric reflux and bile reflux gastritis, congenital biliary atresia, drug-induced liver disease 1. Serum LD in the presence of its substrate (a certain amount of lactic acid in serum) can also restore NAD+ to NADH, resulting in a high blank value. In this method, sodium pyruvate is added to inhibit LD activity, which can effectively reduce the blank absorbance. 2. The concentration of each component in the reaction mixture is: 3α-HSD5U/L Huangyunase 500U/L NAD+1mmol/L NTB0.2g/L pH 7.50 3. The absorbance of the reaction mixture is affected by the protein, so the sodium glycocholate standard solution is prepared in the mixed serum. The original bile acids in the mixed serum and other substances that may be involved in the reaction need to be eliminated by P tube. 4, 3α-HSD products contain di-thiothreitol (DTT), when the amount of enzyme preparation is too much, it can affect the reduction of NTB. 5. This method has a linearity of 250 μmol/L. If serum bile acid exceeds this value, it should be diluted appropriately. 6, NoigenET-180 is a non-ionic surfactant, chemical name polyoxy-ethyleneolylether, produced by Dai-ichi Ko-gyoSeiyaku Co., Kyoto, Japan, added to the reaction mixture to prevent precipitation, does not affect 3α -HSD and diaphorase activity do not affect the sensitivity of the assay system. 7. The TBA content in serum is low, and the specimen contains a large amount of interfering substances, the most important of which is lactate dehydrogenase (LDH). LDH can affect the reduction of NAD+, and NADH produced by LDH tends to be much larger than the amount of NADH produced by the reaction of 3α-HSD-catalyzed TBA. Since all kinds of hepatitis can cause elevated serum LDH, the effect of LDH must be eliminated in the determination. The method includes: serum is heated at 67 ° C for 30 min, oxalic acid is added as a blocking agent for LDH, alkali or acid treatment, or inhibition with sodium pyruvate LDH activity, etc., among which sodium pyruvate method is the best. Interference of other reducing substances By setting up a double reagent, the sample is first incubated with a system without 3α-HSD to react the interfering substances in the sample, and then 3α-HSD is added to react TBA to eliminate interference. Inspection process Follow the instructions in the kit strictly, or refer to Table 1. Mix and 540nm wavelength colorimetric, adjust the corresponding tube B to zero, and measure the absorbance of each tube separately. Not suitable for the crowd Inappropriate people: Generally there are no people who are not suitable. Adverse reactions and risks 1. Infection: Pay attention to aseptic operation when collecting blood, avoid contamination of water and other parts at the blood collection site to avoid local infection. 2, bleeding: after the blood is given a full compression time, especially coagulopathy, bleeding tendency, to avoid local subcutaneous oozing, bruising and swelling.