What does bilirubin mean in diagnosing health problems?

The article was consulted professionally with Master, Doctor Do Thi Hoang Ha - Doctor of Biochemistry - Laboratory of Laboratory - Vinmec Hai Phong International General Hospital.

Bilirubin is derived mainly from the destruction of red blood cells, which is a degradation product of Heme - a component of hemoglobin in red blood cells. The degenerative process takes place in the endothelial reticulum of tissues such as: liver, spleen (after the death of old red blood cells), bone marrow (due to ineffective erythropoiesis) or in the blood (due to the presence of autoantibodies). . Bilirubin in the blood is divided into total bilirubin, direct bilirubin, and indirect bilirubin. These indicators are very useful in diagnosing diseases related to blood, hematopoietic organs, hepatobiliary diseases, infectious diseases, viruses...

Bilirubin is an orange-yellow pigment, a product of the process of destroying normal red blood cells in the blood, then passes through the liver, a small amount is reabsorbed back into the blood, most of it will be eliminated in the blood. bile ducts and into the intestines, and finally out of the body in the feces (mainly) and to a small extent in the urine. The total bilirubin in the serum consists of indirect bilirubin (80%) and direct bilirubin (20%).
Bilirubin TP = Bilirubin GT + Bilirubin TT
Before reaching the liver, bilirubin In the unconjugated form (unconjugated bilirubin), also known as indirect bilirubin (because an indirect method is needed to quantify this bilirubin), this bilirubin is bound to albumin and is not filtered by the kidneys. When it reaches the liver, indirect bilirubin will be retained by liver cells, combined with glucuronides produced by the liver to create a water-soluble form called conjugated bilirubin, also known as direct bilirubin, and excreted. into the bile duct.
When Bilirubin is directly out of the liver into the large intestine, under the action of bacteria, it will be converted into urobilinogen and then into stercobilin, then excreted from the body through feces. Currently, most laboratories will measure direct bilirubin levels, then subtract the direct amount of bilirubin from the total amount (total bilirubin) to get an estimate of the amount of indirect bilirubin in the body.
Indirect bilirubin is quite toxic, insoluble in water and is the transport form of bilirubin in the blood. Direct bilirubin (bilirubin conjugated with glucuronic acid) gives a rapid Diazo reaction, is water soluble and crosses the glomerular membrane.

Total Bilirubin
Newborns with a bilirubin index: < 10 mg/dl or < 171 μmol/L. Over 1 month of age with a bilirubin index: 0.3 - 1.2 mg/dl or 5.1 - 20.5 μmol/L. Adults with a bilirubin level: 0.2 – 1.0 mg/dL or 3.4 – 17.1 μmol/L. Direct Bilirubin
Normal: 0 - 0.4 mg/dl or 0 - 7 μmol/L Indirect Bilirubin
Normal: 0.1 -1.0 mg/dL or 1 - 17 μmol/L Direct Bilirubin/Total Bilirubin Ratio
Normal: < 20%.

A higher than normal amount of direct or indirect bilirubin will have a higher probability of diagnosing hepatobiliary diseases as well as hemolysis.
High Bilirubin will indicate an increasing rate of destruction of red blood cells (red blood cells).
For infants, rapid determination of bilirubin blood levels is also an important method. Timely testing before indirect bilirubin is too high, can cross the blood-brain barrier and deposit in the basal ganglia and brain nucleus, causing brain cell damage in children. Consequences will slow down children's intellectual development, impaired learning and development. In addition, it also causes children to have hearing loss, eye movement disorders or worse, death ...

Gallbladder infection or inflammation of the gallbladder, gallstones... Some genetic diseases such as Gilbert's syndrome (a disease that affects how the liver processes bilirubin). Jaundice can occur in some people with Gilbert's syndrome, but the condition is not usually dangerous. Diseases that cause liver damage such as hepatitis, cirrhosis or mononucleosis. Diseases that cause biliary obstruction such as gallstones, cholangitis, cholangiocarcinoma or pancreatic cancer. Rapid destruction of red blood cells in the blood, such as sickle cell disease, malaria, RH incompatibility in infants, or an allergy to blood received from a blood transfusion. Biermer's anemia (ineffective erythropoiesis), Crigler-Najjar syndrome Hypersplenism, decompensated heart failure In addition, bilirubin may be elevated in pregnant women, neonates and premature infants, who have vigorous physical activity,

When there are abnormal signs of function, the doctor will order a bilirubin test, specifically in the following cases:
Jaundice Drinking too much alcohol Suspecting drug poisoning Exposure to hepatitis virus Urine dark, amber-colored Nausea, vomiting a lot. Abdominal pain or swelling Fatigue, lethargy, and chronic liver disease. Suspected hemolytic anemia. Determination of bilirubin levels in neonates is considered a standard of medical care.

Bilirubin levels in the blood of men will be higher than that of women. Excessive exercise can increase blood bilirubin levels. Medications that can also lower bilirubin levels include: barbiturates, caffeine, penicillin, high-dose salicylate, atazanavir (HIV antivirals can increase bilirubin levels indirectly). Medicines that increase Bilirubin levels such as: antibiotics, some birth control pills, diazepam (Valium), flurazepam, indomethacin (Indocin), and phenytoin (Dilantin)...
Bilirubin can be measured in the amniotic fluid. if the doctor suspects that the fetus has a condition that destroys red blood cells. Usually, when the urine does not contain bilirubin, the doctor will order more tests to find the cause.
During the test, do not eat or drink for 4 hours. Your doctor will advise you to stop taking any medications that may affect the test results. For young children, no special preparation is required before the test.
A amount of blood will be taken for testing, blood drawn from a vein in the arm or hand with a needle, and then stored in a test tube. After taking blood, it is necessary to put a bandage on the injection site for 10-20 minutes, avoid lifting objects quickly after taking blood.
Vinmec International General Hospital is one of the hospitals that not only ensures professional quality with a team of leading medical doctors, modern equipment and technology, but also stands out for its examination and consultation services. comprehensive and professional medical consultation and treatment; civilized, polite, safe and sterile medical examination and treatment space. Customers when choosing to perform tests here can be completely assured of the accuracy of test results.