Hepatitis B Surface Antigen - HBsAg (CMIA)
The Hepatitis B Surface Antigen (HBsAg) Test – CMIA Method is a blood test used to detect the presence of the Hepatitis B virus (HBV) surface antigen. The presence of HBsAg indicates an active Hepatitis B infection, which may be acute or chronic.
This test uses the CMIA (Chemiluminescent Microparticle Immunoassay) technique, known for its high sensitivity and accuracy, enabling early detection of the virus.
The purpose of this test is to:
- Detect Hepatitis B surface antigen (HBsAg) in blood
- Diagnose active Hepatitis B infection
- Screen individuals for HBV infection
- Identify both acute and chronic Hepatitis B
- Support monitoring of infection status
HEPATITIS B SURFACE ANTIGEN - HBSAG (CMIA) Test
The Hepatitis B Surface Antigen (HBsAg) – CMIA test detects the surface antigen of the hepatitis B virus (HBV) in a blood sample. HBsAg is one of the primary markers used to identify a current hepatitis B infection.
The test can help detect both acute and chronic hepatitis B infection and is commonly used for screening, particularly when there is a possible exposure to HBV or a risk of infection. It is also routinely included in antenatal screening to help identify pregnant women who may have HBV infection and require appropriate medical management.
A positive HBsAg result generally indicates a current HBV infection, but additional tests may be required to determine whether the infection is acute or chronic and to assess the level of viral activity. These may include Anti-HBc IgM, HBeAg, Anti-HBe, Anti-HBs, and HBV DNA.
HEPATITIS B SURFACE ANTIGEN - HBSAG (CMIA)
Test is Recommended for Individuals:
- Individuals being screened for hepatitis B infection
- People with a recent or possible exposure to HBV
- Individuals with risk factors for hepatitis B
- Pregnant women as part of recommended antenatal screening
- People with unexplained liver enzyme abnormalities
- Individuals with symptoms suggestive of hepatitis
- Patients monitoring a previously diagnosed hepatitis B infection
- Healthcare or other individuals with occupational exposure concerns, as advised
- Individuals recommended for testing by their healthcare provider
FAQs
1. What does a positive HBsAg result mean?
A positive HBsAg result generally indicates that hepatitis B virus is currently present in the body. Further testing is usually needed to determine whether the infection is recent (acute) or long-standing (chronic).
2. Does HBsAg detect hepatitis B immunity?
No. HBsAg detects a marker of current HBV infection. Immunity following vaccination or past resolved infection is generally assessed using Anti-HBs, often together with other hepatitis B markers.
3. Is HBsAg testing recommended during pregnancy?
Yes. HBsAg screening is routinely recommended during pregnancy because identifying HBV infection allows appropriate steps to reduce the risk of transmission of hepatitis B from mother to baby.