Testing for Hep B

Testing for Hep B

Many people with hepatitis B have no signs of illness and do not realise they have the virus in their body. Hepatitis B is diagnosed through various blood tests, which look for markers of the hepatitis B virus in the blood. You can ask your doctor about having a blood test for hepatitis B.

To understand the tests, it is important to understand two basic medical terms:

  • antigen—a foreign substance in the body, such as the hepatitis B virus; and
  • antibody—a protein that the immune system makes in responses to a foreign substance. Antibodies can be produced in response to a vaccine or a natural infection.

Other test results may indicate some liver damage and prompt the doctor to suggest a test for hepatitis B. These test may also be conducted once a person is diagnosed to help identify changes in liver function and support decisions regarding the timing of treatment. Some of these test include:

  • Liver Function Tests (LFTs): are a group of blood tests that show how well your liver is working. One important test is the Alanine Aminotransferase (ALT). The ALT is released from liver cells into the bloodstream when the liver is injured. An ALT level above normal may indicate liver damage. ALT levels are included in the regular monitoring of all chronic hepatitis B patients; this test can also be useful in deciding whether a patient would benefit from treatment, or for evaluating how well a current treatment is working;
  • Fibroscan (transient elastography) is a non-invasive test used to check for possible liver scarring; and
  • Alpha-fetoprotein: is a blood test which can sometimes detect liver cancer

Page Updated: 05 Feb 2013