Interpreting the Hepatitis B Serologic Panel

The hepatitis B blood tests are collectively known as the serologic panel. This set of tests can accurately diagnose current and past hepatitis B infection. Since there are a number of markers and at least six interpretations of the various results, determining their meaning can be challenging. To help clarify, below are the six interpretations organized in a table from these hepatitis B markers.

Tests in the Hepatitis B Serologic Panel

The serological panel for hepatitis B includes several tests that check for the presence of specific antibodies or proteins in a sample of your blood:

• HBsAg (hepatitis B surface antigen): This is a protein that is found on the surface of the hepatitis B virus molecule, a part of the virus itself. When they find a significant concentration in your blood, it shows you have a hepatitis B virus infection, which may be chronic or acute. This protein sets off your body's immune response, and if your immune system is functioning correctly you will soon produce measurable levels of anti-HBs antibody. The hepatitis B vaccine uses this antigen to stimulate immunity to the virus.
• Anti-HBs (also called HBsAb, hepatitis B surface antibody): Your body produces this antibody when it is exposed to HBsAg, whether from being infected with hepatitis B or being stimulated with the hepatitis B vaccine. It is a sign that you are recovering from a hepatitis B infection or that you have had a good response to the vaccine and should have protection from the virus.
• Anti-HBc (also called HBcAb, hepatitis B core antibody): Your body develops this antibody in response to the presence of the hepatitis B virus at about the time you show symptoms of acute infection. Once you produce it, you generally will continue to make it the rest of your life and so your blood test will remain positive for anti-HBc. It shows that you have an infection or that you had one in the past, but it doesn't tell your healthcare provider which is the case.
• IgM HBcAb (or IgM anti-HBc) is a test for evidence of a type of antibody that your immune system produces during or just after an acute hepatitis B infection. A positive test usually indicates an acute or recent infection. The antibody is greatly reduced or disappears after the infection is resolved. 

The Centers for Disease Control and Prevention recommends that all adults get screened for hepatitis B at least once in their lifetime. For the initial screening, your healthcare provider may order a "triple panel" comprising the HBsAg, anti-HBs, and anti-HBc tests.

If you're acutely or chronically infected with hepatitis B, then it's possible for you to spread the virus to others. Follow standard prevention and make sure to protect yourself and others during sexual contact.

6 Interpretations of the Serologic Panel

1. If Your Tests Are:

• HBsAg negative
• Anti-HBc negative
• Anti-HBs negative

You're probably susceptible to hepatitis B. If you are eligible for the hepatitis B vaccine, you could get vaccinated to reduce your risk of infection in the future.

2. If Your Tests Are:

• HBsAg negative
• Anti-HBc positive
• Anti-HBs positive

You're probably immune due to natural infection. You don't have the viral antigen circulating, but you are showing both antibodies. The core antibody is the one that indicates this was due to infection rather than vaccination. Often people are surprised to learn they had an infection in the past, as many cases have only minor symptoms.

3. If Your Tests Are:

• HBsAg negative
• Anti-HBc negative
• Anti-HBs positive

You're probably immune due to hepatitis B vaccination. Often this is the result seen on follow-up after immunization and it is a good outcome. If you weren't vaccinated, that is something your healthcare provider will explore further.

4. If Your Tests Are:

• HBsAg positive
• Anti-HBc positive
• IgM anti-HBc positive
• Anti-HBs negative

You're probably acutely infected. The presence of IgM anti-HBc, along with HBsAg, shows that there is virus circulating in your body and you are producing an early reaction to it. This wouldn't be the case with a chronic infection or an infection further in the past that you recovered from.

5. If Your Tests Are:

• HBsAg positive
• Anti-HBc positive
• IgM anti-HBc negative
• Anti-HBs negative

You're probably chronically infected. You are continuing to make core antibody and you have virus circulating, but your early IgM antibody has faded away. In this case, your healthcare provider will most likely obtain liver function tests and viral DNA levels to determine eligibility for treatment.

6. If Your Tests Are:

• HBsAg negative
• Anti-HBc positive
• Anti-HBs negative

With this result, it could be several things, the most common of which is that you had a hepatitis B infection that has resolved or is resolving. You probably aren't in the acute infection stage. You might have a false-positive test for the core antibody. You aren't immune to hepatitis B, so you need to take care of exposure risk and you should discuss whether vaccination is advised. You may also have a low-level chronic hepatitis B infection.