From the Guidelines
Hepatitis B testing is universally recommended for all adults aged 18 years by testing for HBsAg, anti-HBs, and total anti-HBc, as per the latest guidance from the Centers for Disease Control and Prevention (CDC) 1. The standard testing panel for hepatitis B includes hepatitis B surface antigen (HBsAg), hepatitis B surface antibody (anti-HBs), and hepatitis B core antibody (anti-HBc).
- A positive HBsAg indicates current infection,
- while positive anti-HBs suggests immunity from vaccination or resolved infection.
- Positive anti-HBc indicates previous exposure to the virus. For acute infection diagnosis, additional tests like HBeAg and liver function tests may be ordered. Testing is crucial because hepatitis B can remain asymptomatic while causing liver damage, and early detection allows for appropriate monitoring, treatment with antivirals like entecavir or tenofovir when indicated, and prevention measures to protect others from infection. Regular screening is particularly important for high-risk groups to prevent complications like cirrhosis and liver cancer. It is also important to note that individuals who meet criteria for treatment of HBV based on current clinical practice guidelines should receive antiviral therapy regardless of their risk of HBV reactivation 1. The CDC recommends continued periodic testing while the exposure persists, and it is reasonable to test initially for serologic markers alone (at minimum for HBsAg, anti-HBc) followed by viral load testing (HBV-DNA) if HBsAg and/or anti-HBc is positive 1. Laboratory tests for patients with CHB should include HBeAg and anti-HBe, as HBeAg positivity generally indicates a high level of viral replication, and anti-HBe positivity a low level 1. Serum HBV DNA and AST/ALT levels are important parameters in HBeAg-negative patients, and HBeAg-negative, anti-HBe-positive patients with a normal ALT level and an HBV DNA level of <2,000 IU/mL may be in the inactive phase 1. Overall, hepatitis B testing is a crucial step in the prevention and management of hepatitis B infection, and it is essential to follow the latest guidelines and recommendations to ensure effective testing and treatment strategies.
From the Research
Hepatitis B Testing
- Hepatitis B testing is crucial for identifying individuals infected with the hepatitis B virus (HBV) and for preventing the spread of the infection 2.
- The American College of Physicians and the Centers for Disease Control and Prevention recommend screening for HBV in high-risk persons, including those born in countries with high HBV prevalence, men who have sex with men, and persons who inject drugs 2.
- The screening test for HBV typically includes hepatitis B surface antigen (HBsAg), antibody to hepatitis B core antigen (anti-HBc), and antibody to hepatitis B surface antigen (anti-HBs) 2.
Interpretation of Test Results
- A positive HBsAg test result indicates current infection with HBV 2.
- A positive anti-HBc test result indicates past or current infection with HBV 2.
- A positive anti-HBs test result indicates immunity to HBV, either through vaccination or past infection 2.
Vaccination and Testing
- The hepatitis B vaccine is recommended for all unvaccinated adults at risk for HBV infection, including healthcare workers, travelers to HBV-endemic regions, and individuals with high-risk behaviors 2.
- Some individuals may not respond to the hepatitis B vaccine, and alternative vaccination strategies, such as intranasal vaccination, may be effective in inducing an immune response in these individuals 3.
Predictive Value of Anti-HBc
- Baseline serum anti-HBc level has been shown to predict HBeAg seroconversion in patients with HBeAg-positive chronic hepatitis B after antiviral treatment 4.
- A higher baseline anti-HBc level is associated with a higher likelihood of HBeAg seroconversion, suggesting that anti-HBc may be a useful marker for predicting treatment response 4.