When and why

Bilirubin is a compound that is produced when red blood cells are broken down. Due to its distinctive orange or yellow colour, a build-up of bilirubin in the blood can lead to jaundice (yellowing of the skin).

A bilirubin test is a type of blood test which helps measure liver function. In the context of HIV infection, it is often used to monitor for toxicity to antiretroviral therapy or to help assess liver function in people with viral hepatitis coinfection. The bilirubin test is also used in the diagnosis or monitoring of a wide range of blood and liver conditions.

Your doctor will take a blood sample drawn from your vein and send it to the lab for analysis.

Total serum bilirubin (the total amount of bilirubin in the blood) is normally less than 20 µmol/L (1.2 mg/dL).

A urine dip test can indicate elevated bilirubin, although a blood test will always be performed to establish an exact level.

How it will help

Elevated bilirubin indicates either a blockage in the way bilirubin is cleared from the blood by the liver or a massive breakdown of red blood cells. Causes may include liver disease, blood disease or drug toxicity. Some people may be genetically prone to bilirubin elevations when taking the protease inhibitor atazanavir.

In a person taking antiretroviral drugs, high bilirubin may lead to a review of drug treatment and a possible dose reduction.