Bilirubin is a yellowish pigment that is created when older red blood cells break down and are replaced by new red blood cells. Before it reaches the liver, bilirubin is called unconjugated (uncombined) bilirubin. In the liver, it is combined with sugars and called conjugated (combined) bilirubin. Once the conjugated bilirubin leaves the liver and goes to the colon, it is converted back to unconjugated (uncombined) bilirubin and is excreted as unconjugated bilirubin. A small amount of the bilirubin is excreted in the urine.

Bilirubin is the cause of the yellowish color of bruises and contributes to the yellowish color of the urine. There are two types of bilirubin created and this test measures the total amount of both types of bilirubin.
One of the reasons for the total bilirubin test is if someone has jaundice (yellowing of the skin or whites of the eyes). Jaundice generally indicates liver disease, a gall bladder problem or a higher than normal breakdown of red blood cells.

Normal Results

Normal total bilirubin levels are:
0.3 to 1.9 mg/dL (milligrams per one tenth of a literdeciliter)

Hemolytic anemia (Anemia is when there are not sufficient red blood cells and hemolytic means the destruction of red blood cells. Hemolytic anemia means earlier than normal destruction of red blood cells.)
Cirrhosis (Scar tissue in the liver)
Hepatitis (Inflammation of the liver)
Gilbert’s disease (Hereditary disease with increased bilirubin)
Cancer of the pancreas
Cancer of the gallbladder
Gallstones (hard mass formed in the gallbladder or bile ducts)

Lower than Normal Levels of Bilirubin

There are not any medical conditions associated with lower than normal levels of bilirubin.