Bilirubin, Total, Serum

The Bilirubin test measures the levels of bilirubin, a yellow compound that forms when the liver breaks down red blood cells. Bilirubin is processed by the liver and excreted in bile, which is stored in the gallbladder and later released into the intestines. The test measures both total bilirubin (which includes both direct and indirect forms) and sometimes separates them into direct (conjugated) bilirubin and indirect (unconjugated) bilirubin. Elevated bilirubin levels can indicate liver dysfunction, bile duct problems, or red blood cell breakdown issues.

The bilirubin test is often used to evaluate liver function and detect problems related to the liver, gallbladder, or red blood cells. Elevated bilirubin levels can lead to jaundice, which causes a yellowing of the skin and eyes. High bilirubin levels can indicate liver conditions like hepatitis, cirrhosis, or liver cancer, as well as bile duct obstructions or conditions affecting red blood cells, such as hemolytic anemia. The test may also be used to monitor treatment for liver diseases or to assess newborns for neonatal jaundice.

• People with symptoms of liver disease, such as yellowing of the skin or eyes (jaundice), dark urine, pale stools, abdominal pain, or unexplained fatigue
• Those with gallbladder disease or suspected bile duct obstructions (e.g., gallstones or tumors)
• Newborns who may develop neonatal jaundice, a common condition in which bilirubin builds up in the blood
• Individuals with hemolytic anemia or other conditions that cause excessive breakdown of red blood cells
• People who are undergoing treatment for liver disease or monitoring liver function

The bilirubin test is an important tool in assessing liver function, diagnosing jaundice, and monitoring liver diseases. Total bilirubin includes both direct (conjugated) bilirubin, which is water-soluble and excreted in bile, and indirect (unconjugated) bilirubin, which is not water-soluble and must be processed by the liver to become conjugated.