Jaundice - Causes of jaundice

Jaundice is caused by a build-up of a substance called bilirubin in the blood and tissues of the body.

Any condition that disrupts the movement of bilirubin from the blood to the liver and out of the body can cause jaundice.

What is bilirubin?

Bilirubin is a waste product that's produced when red blood cells break down. It is transported in the bloodstream to the liver, where specialised cells help to combine it with a digestive fluid called bile.

The bile and bilirubin is converted into a substance called urobilinogen by bacteria inside the digestive system, which is passed out of the body in urine or stools. It is bilirubin that gives urine its light yellow colour and stools their dark brown colour.

Types of jaundice

There are three types of jaundice, depending on what is affecting the movement of bilirubin out of the body.

• Pre-hepatic jaundice occurs when a condition or infection speeds up the breakdown of red blood cells. This results in an increase in bilirubin levels in the blood and triggers the symptoms of jaundice.
• Intra-hepatic jaundice occurs when a problem in the liver, for example damage as the result of infection or exposure to a harmful substance (such as alcohol), disrupts the liver’s ability to process bilirubin.
• Post-hepatic jaundice is triggered when the bile duct system is damaged, inflamed or obstructed, which results in the gallbladder being unable to move bile into the digestive system.

The causes of each type of jaundice are described below.

Pre-hepatic jaundice

Causes of pre-hepatic jaundice include:

• malaria – a blood-borne infection spread by mosquitoes and common in tropical areas of the world
• sickle cell anaemia – a genetic condition that causes red blood cells to develop abnormally; it is most common among black Caribbean, black African and black British people
• thalassaemia – a similar genetic condition to sickle cell anaemia in that it affects the production of red blood cells; it is most common in people of Mediterranean, Middle Eastern and, in particular, South Asian descent
• Crigler-Najjar syndrome – a rare genetic condition where an enzyme that's needed to help move bilirubin out of the blood and into the liver is missing
• hereditary spherocytosis – an uncommon genetic condition that causes red blood cells to have a much shorter life span than normal

Intra-hepatic jaundice

Causes of intra-hepatic jaundice include:

• the viral hepatitis group of infections – hepatitis A, hepatitis B and hepatitis C
• alcoholic liver disease – where the liver is damaged as a result of alcohol misuse
• leptospirosis – a bacterial infection that's spread by animals, particularly rats; it's common in tropical areas of the world and uncommon in the UK
• glandular fever – a viral infection caused by the Epstein-Barr virus
• drug misuse – two leading causes are the recreational drug ecstasy and overdoses of paracetamol
• primary biliary cirrhosis – a rare and poorly understood condition that causes progressive liver damage
• Gilbert's syndrome – a common genetic condition where the liver has problems breaking down bilirubin at a normal rate
• liver cancer – a rare and usually incurable cancer that develops inside the liver
• exposure to substances known to be harmful to the liver, such as phenol (used in the manufacture of plastic) or carbon tetrachloride (widely used in the past in processes such as refrigeration, although now its use is strictly controlled)
• autoimmune hepatitis – a rare condition where the immune system starts to attack the liver
• primary sclerosing cholangitis – a rare type of liver disease that causes chronic (long-lasting) inflammation of the liver
• Dubin-Johnson syndrome – a rare genetic condition where the liver is unable to combine bilirubin with bile and move it out of the liver

Post-hepatic jaundice

Causes of post-hepatic jaundice include:

• gallstones obstructing the bile duct system
• pancreatic cancer – an uncommon type of cancer that develops inside the pancreas (a gland that helps with the digestion of food)
• gallbladder cancer or bile duct cancer, which are both relatively rare types of cancer
• pancreatitis – inflammation of the pancreas, which can either be acute pancreatitis (the inflammation only lasts for a few days) or chronic pancreatitis (the inflammation lasts for many years)