This page helps you to understand blood test results for Bilirubin and gives you the reference range to determine if your lab test results mean that you have high bilirubin, low bilirubin or normal bilirubin levels.
We outline the risk factors associated with raised Bilirubin levels.
Reference Ranges for Bilirubin Total (Please sign up to see Bilirubin direct):
|US Conventional Units||umol/L||<=21||>=22|
|Standard International Units||umol/L||<=21||>=22|
What is Bilirubin
Bilirubin is an orange-yellow waste product made during the normal breakdown of red blood cells. Bilirubin passes through the liver and is excreted out of the body. Bilirubin is also part of bile, which your liver makes to help digest the food you eat. Direct (conjugated) bilirubin travels freely through your bloodstream to your liver. Most of this bilirubin passes into the small intestine. A very small amount passes into your kidneys and is excreted in your urine. Bilirubin that is bound to a certain protein is called indirect (unconjugated) bilirubin .
Function of Bilirubin
Very recently, bilirubin has been shown to possess important functions as an antioxidant, but it also serves simply as a means to excrete unwanted heme, derived from various heme-containing proteins such as hemoglobin and myoglobin. Bilirubin is also notable for the fact that it provides color to the bile and stool, as well as, to a lesser extent, the urine .
Risk factors associated with Bilirubin
Your doctor will interpret your result for each biomarker in the context of the overall test and determine if your result warrants further investigation.
Higher than normal levels of bilirubin may indicate different types of liver problems. Occasionally, higher bilirubin levels may indicate an increased rate of destruction of red blood cells (hemolysis) .
Sometimes the liver can’t process the bilirubin in the body. This can be due to an excess of bilirubin, an obstruction, or inflammation of the liver. When your body has too much bilirubin, your skin and the whites of your eyes will start to yellow. This condition is called jaundice, and in a newborn can be very serious and life-threatening if left untreated .
Notable variations by Demographic Group
Men have slightly higher levels of bilirubin than women. African Americans also have slightly higher levels of bilirubin than people of other ethnic backgrounds .