Jaundice
Jaundice is a yellowish discoloration of the skin and of the whites of the eyes caused by abnormally high levels of the pigment bilirubin in the bloodstream.
Old or damaged red blood cells are constantly being removed from the circulation, mainly by the spleen. During this process, hemoglobin, the part of red blood cells that carries oxygen in the blood, is broken down into a dark greenish yellow pigment called bilirubin. Bilirubin is then carried in the bloodstream to the liver and is excreted into the intestine as a component of bile (the digestive fluid produced by the liver). If bilirubin cannot be excreted into the bile quickly enough, it builds up in the blood. The excess bilirubin gets deposited in the skin, resulting in the yellowish discoloration called jaundice.
High levels of bilirubin in the blood may result from problems originating either within the liver or outside the liver. Damage to the liver, such as from inflammation or scarring, can hinder its ability to excrete bilirubin into bile. Alternatively, the bile ducts, which carry the bile from the liver to the small intestine, may be blocked, for example, by a gallstone or a tumor. Less commonly, an overproduction of bilirubin, due to excessive breakdown of red blood cells, can overwhelm the liver with more than the liver is capable of processing. This is most common in newborns with jaundice (see Section 23, Chapter 264).
In Gilbert's syndrome, bilirubin levels are slightly increased but usually not enough to cause jaundice. This disorder, which is sometimes hereditary, is most often detected in young adults during routine screening tests. It has no other symptoms and causes no problems.
People who eat large amounts of carrots may develop a mild yellow tint to the skin, but their eyes do not turn yellow. This is not jaundice and is unrelated to liver disease.
Symptoms
In jaundice, the skin and the whites of the eyes appear yellow. The urine is often dark because excess bilirubin is excreted through the kidneys. Other symptoms, such as itching and light-colored stools, may appear, depending on the underlying cause of the jaundice. For example, acute inflammation of the liver (acute hepatitis) may cause loss of appetite, nausea, vomiting, and fever. Blockage of bile may produce the symptoms of cholestasis.
Diagnosis and Treatment
A doctor uses laboratory tests and imaging studies to determine the cause of the jaundice. If the problem is a disease of the liver itself, such as acute viral hepatitis, the jaundice usually gradually disappears as the condition of the liver improves. If the problem is blockage of a bile duct, then surgery or endoscopy (a procedure involving use of a flexible viewing tube with surgical attachments (see Section 9, Chapter 119)) is usually performed as soon as possible to reopen the affected bile duct.
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