Increased bilirubin production
This pigment comes from the degradation of red blood cells. Thus, an increase in bilirubin production is probably because the blood is degrading rapidly. This is known as accelerated hemolysis and happens after you have a large hematoma and certain blood conditions that affect the form of erythrocytes. Immune conditions that destroy your red blood cells may also increase bilirubin production. The liver has a threshold above which the organ becomes overwhelmed. Thus, bilirubin is produced faster than liver metabolism, accumulating in the blood.