Someone with jaundice is likely to have a yellow look to their skin and the whites of the eyes.
Many newborn babies develop jaundice, but the condition can affect people of all ages. This article looks at older children and adults.
Jaundice is caused by a build-up of bilirubin in the blood and body tissue. That build-up is often due to conditions affecting the liver, such as cirrhosis, hepatitis or gallstones.
If someone shows signs of jaundice, doctors will look to treat the condition that's causing it rather than jaundice itself.
If you have signs of jaundice, seek medical advice.
Symptoms of jaundice
As well as the classic yellow tinge to the skin and whites of the eyes, someone with jaundice may also have yellowing of mucous membranes in the mouth and nose.
Stools (faeces or poo) can be pale in colour and urine dark in colour.
Some underlying conditions, which lead to jaundice, may feel like flu, and may also result in fever, chills, stomach pain, itching or weight-loss or be without an explanation such as a diet.
Causes of jaundice
When red blood cells break down naturally in a 120-day cycle, bilirubin is produced as a waste by-product.
The journey bilirubin takes out of the body's waste disposal systems sees it carried by blood to the liver. There is it combined with bile (digestive fluid) from the gallbladder.
This mixture exits the body through faeces and urine. If everything is working well, faeces should be brown and urine light yellow.
Infections or damage can disrupt this process, leading to jaundice.
If an infection or medical condition makes the red blood cells break down sooner than usual, bilirubin levels rise. This is known as pre-hepatic jaundice.
Conditions that may trigger this include malaria, sickle cell anaemia, thalassaemia, Gilbert's syndrome, hereditary spherocytosis and Crigler-Najjar syndrome.
If the liver is damaged, it may be less able to process bilirubin. This causes what doctors call intra-hepatic jaundice.
The liver damage may be a result of causes that include hepatitis, alcoholic liver disease, glandular fever, liver cancer, illegal drug use including ecstasy, and paracetamol overdose.
Obesity and non- alcoholic fatty liver disease can be a cause of cirrhosis of the liver and jaundice.
Gallstones, pancreatitis, pancreatic cancer and cancers of the gallbladder or bile duct may also disrupt the bilirubin removal process leading to jaundice. This is called post-hepatic jaundice.
Eating a high-fat diet can raise your cholesterol levels and increase the risk of having gallstones.
The yellowing of skin and eyes are likely to be the main clues a doctor will use before confirming a jaundice diagnosis.
A person will be asked about other symptoms and risks, such as foreign travel or drug misuse.
A physical examination will be carried out to look for signs of swelling of the liver and legs, ankles or feet, which might indicate cirrhosis of the liver.
Urine can be tested for urobilinogen, which is produced when bilirubin is broken down. Finding high or low levels can help pinpoint the type of jaundice.
Blood tests may be used to check for conditions like malaria or hepatitis.
A liver function blood test may indicate hepatitis, cirrhosis or alcoholic liver disease. Sometimes a liver biopsy - removal of small tissue sample - is needed to confirm or rule out conditions such as cirrhosis or liver cancer.
Doctors may also need to look inside the body for problems with the liver or bile duct using ultrasound, X-ray with contrast, MRI or CT scans.