Jaundice, a disorder symptomatic of several blood and liver diseases, is characterized by yellowing of the skin and mucous membranes, particularly the white of the eyes. It is caused by the excess production or inadequate excretion of bilirubin, which is a yellow bile pigment that is formed from hemoglobin breakdown products after red blood cells decompose.
Because red blood cells continually wear out and break down, bilirubin is usually present, in small amounts, in blood plasma. It is excreted from the liver into the intestines through the bile ducts. Hemolytic jaundice occurs when red blood cells are destroyed excessively, as in some forms of anemia or sepsis (an infection of the bloodstream) or the transfusion of an incompatible blood type. Hepatogenous jaundice is caused by liver damage, particularly hepatitis, the ingestion or inhalation of toxic chemicals, or cirrhosis. Obstructive jaundice results from blockage of the bile ducts, usually by gallstones or tumors.
Newborn infants frequently develop mild hemolytic jaundice, which lasts several days until a normal excess of red blood cells is destroyed. Erythroblastosis fetalis, a serious form of jaundice in infants, generally is due to an Rh factor incompatibility. Adolescents and young adults who have a viral inflammation of the liver often develop jaundice; jaundice in middle-aged adults is commonly due to gallstones. In older adults jaundice may signal cancer of the liver or the bile ducts. It is often the first symptom of liver damage in alcoholics.