Indirect Bilirubin Blood Test - Indirect Bilirubin Test

A specific measurement of the level of unconjugated bilirubin in the blood. This type of bilirubin is primarily produced from the breakdown of hemoglobin in aged red blood cells. Before it can be excreted in bile, it must be conjugated with glucuronic acid in the liver to become "direct." Elevated levels reflect problems in the pre-existing stage of hepatic metabolism, most notably increased hemolysis (hemolytic anemia).