Yellow discoloration of the skin and the whites of the eyes
Jaundice, a yellow discoloration of the skin and the whites of the eyes, is a symptom of many disorders of the liver, gallbladder, or pancreas. It may also be caused by some blood disorders. Jaundice results from excessively high blood levels of the pigment bilirubin, a breakdown product of red blood cells. Bilirubin is processed by the liver and then excreted as a component of the digestive fluid bile.
Jaundice always requires investigation because the underlying disorder may be serious. A few days after birth, many babies develop a form of jaundice that is usually harmless and disappears quickly (see Neonatal jaundice).
Levels of bilirubin in the blood can increase if the amount of bilirubin produced is too great for the liver to process. Damaged liver cells or obstruction of the bile ducts, which carry bile from the liver to the gallbladder and small intestine, can also lead to high levels of bilirubin in the blood.
In a healthy person, red blood cells have a lifespan of about 120 days, after which they are removed from the blood and broken down by the spleen to produce bilirubin. The bilirubin then passes to the liver. If the number of red blood cells being broken down is above normal, the liver cannot process the large amounts of bilirubin produced. This condition is known as haemolytic jaundice and may be caused by disorders such as haemolytic anaemia, in which the lifespan of red blood cells is shorter than normal. It may be accompanied by other symptoms, such as tiredness.
If the liver cells are damaged, the liver is less able to process bilirubin. Possible causes of damage include infection (see Acute hepatitis, and Chronic hepatitis), alcohol abuse (see Alcohol-related liver disease), and an adverse reaction to some drugs. Jaundice that is due to liver cell damage is sometimes accompanied by nausea, vomiting, and abdominal pain and swelling.
An obstruction in the bile ducts, the channels through which bile leaves the liver, may result in jaundice. Obstruction may be due to disorders such as pancreatic cancer or gallstones. If bile ducts are blocked, bile builds up in the liver, and bilirubin is forced back into the blood. This type of jaundice may be accompanied by itching, dark-coloured urine, and paler than normal faeces.
Your doctor may arrange blood tests to assess liver function and to look for signs of excess red blood cell destruction, viral hepatitis, or other disorders affecting the liver. Ultrasound scanning of your liver and gallbladder may be carried out, and sometimes also more detailed imaging techniques, such as CT scanning, MRI, ERCP, or endoscopic ultrasound (in which a viewing tube with an ultrasound probe attached is inserted into the body). A sample of liver tissue may also be taken and examined for underlying liver disease (see Liver biopsy).
If the underlying cause of jaundice can be treated, jaundice will disappear. If the cause is not curable, as in the case of advanced pancreatic cancer, treatment may be given to relieve symptoms associated with jaundice, such as itching.
From the 2010 revision of the Complete Home Medical Guide © Dorling Kindersley Limited.