Hepatitis B Serology Interpretation
The given serology results are:
- Hepatitis B surface antigen (HBsAg) negative
- Hepatitis B core antibody (HBcAb) total positive
- Hepatitis B core IgM (HBcAb IgM) negative
- Hepatitis B surface antibody (HBsAb) negative
Differential Diagnoses
- Single most likely diagnosis
- Chronic Hepatitis B infection in an inactive carrier state: This is likely because the presence of total core antibodies (indicating past or current infection) without the surface antigen suggests that the individual is not currently infectious but has been infected in the past. The absence of IgM core antibodies indicates that this is not an acute infection. The lack of surface antibodies (which would indicate immunity) suggests that the individual is not immune and could potentially reactivate.
- Other Likely diagnoses
- Resolved Hepatitis B infection: Although less likely given the absence of surface antibodies, it's possible that the individual has resolved the infection but for some reason does not have detectable surface antibodies.
- Vaccination failure or waning immunity: If the individual was vaccinated but did not respond or has waning immunity, they might not have detectable surface antibodies but could still have core antibodies from a past, resolved infection.
- Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
- Hepatitis B infection with mutant surface antigen: Some mutations in the hepatitis B virus can lead to false-negative surface antigen tests. This is a critical diagnosis not to miss because it could lead to inappropriate management and transmission risk.
- Immunosuppression-related reactivation: In individuals with compromised immune systems, hepatitis B can reactivate even if they have been previously infected and cleared the virus. This can lead to severe disease and is crucial not to miss.
- Rare diagnoses
- False-positive core antibody due to other conditions: Certain conditions can cause false-positive results for hepatitis B core antibodies, though this is rare.
- Co-infection with other hepatitis viruses: Co-infection with other hepatitis viruses could potentially alter the typical serological profile, though the specific pattern here is more suggestive of hepatitis B.