What is the interpretation of Hepatitis B markers?
Q: I recently underwent a routine medical check up in my company. The report suggests that my HbsAg is 3.736, which is positive. They checked this using a bioMerieux-Elisa equipment. I underwent another blood test, the report of which suggests HbsAg (EIA) – positive; Anti HBc-IgM (chemiluminescence) is less than 2; Anti HBc-Total (chemiluminescence) is positive. Anti HBs (chemiluminescence). Interpretation: suggestive of chronic infection with Heptatitis B Virus. Suggested correlation with other Hepatitis B virus makers. What is the treatment? What precautions do I need to undertake? Please give more details about this disease.
A:Hepatitis B virus (HBV) is transmitted by blood and sexually. The outcome of the infection depends on the interaction between the virus and the host's immunity and may manifest as an acute symptomatic disease (acute hepatitis) or an asymptomatic disease (immune to HBV or a chronic carrier state). Some of these patients go on to develop cirrhosis of the liver and hepatocellular carcinoma. Antiviral treatment is effective in about one third patient while liver transplant may be the only treatment option for late stages of the disease (in select cases). Chronic hepatitis may be of 2 types chronic inactive hepatitis B (healthy carriers) or chronic active hepatitis B. Healthy carriers have normal liver enzymes (AST and ALT) and the markers of infectivity (HBeAg, HBV DNA) may be negative. But HBsAg, HBcAb of IgG type, and HBeAb are present in the blood. Patients with chronic active hepatitis B have mild-to-moderate elevation of the liver enzymes (<5 times the upper limit of normal), high HBV DNA levels and presence of HBsAg and HBcAb (IgG or IgM) in the blood. Treatment is recommended for patients with chronic active hepatitis and the drugs currently used include interferon alfa, lamivudine, and adefovir dipivoxil. Many other agents (entecavir, emtricitabine, DAPD, clevudine etc) are being actively investigated. There is no diet restriction for patients with acute and chronic hepatitis. Healthy carriers should have annual blood tests to check the liver enzyme levels while those with chronic active hepatitis should have blood tests (liver enzyme levels, HBV serology and viral load), a liver biopsy and be put on treatment. Review with your physician all medicines you take as some can damage the liver and avoid alcohol. People can get HBV infection from you by coming in contact with your blood, serum or semen. Cover all cuts and open sores with a bandage, wash your hands well after touching your blood or body fluids and throw away used personal items such as tissues etc. in a bag so others will not be exposed to your blood. Do not share toothbrushes, razors, nail clippers/scissors, washcloths, or anything that may have come in contact with your blood or body fluids. Do not donate blood. You would need to tell your partner that you are infected and she would need to see a doctor for HBV testing and appropriate immunisation. All household members must see the doctor and be tested for the disease. There are many markers of hepatitis B virus (HBV) and they connote different things. The surface antigen (HbsAg) is the marker of infection and is the first to appear in an infected person. If it persists for longer than 6 months, it signifies chronic hepatitis B. The E-antigen (HbeAg) indicates active replication while the e-antibody (anti-Hbe) generally indicates inactive virus. The appearance of surface antibody (anti-HBs) signifies recovery or immunity so that if an individual has had natural infection, which cleared, he/she will have surface antibody. This antibody also develops following hepatitis B vaccine. The hepatitis core antibody (anti-Hbc) indicates present or past infection. When an individual is infected with hepatitis B, they test positive for surface antigen and develop the core antibody. Following recovery, the HbsAg is lost and the surface antibody appears but the core antibody persists. The core antibody appears at the time of infection and persists for life. People who have natural immunity will have both antibodies; the surface antibody (anti-HBs) and the core antibody (anti-HBc) while people who are vaccinated and protected will only have one antibody, the surface antibody (anti-HBs). In general, the following is the interpretation of various markers:
- Hepatitis B surface antigen (HBsAg): Marker of current infection (acute or chronic)
- Hepatitis B surface antibody (anti-HBs): Marker of recovery or immunity (acquired through natural HBV infection, vaccination, or passive antibody immunisation)
- Hepatitis B core antibody (anti-HBc): Marker of present or past infection - IgM - indicative of infection in the previous six months - IgG - indicative of more distant HBV infection that may have been cleared by the immune system or that may persist; A positive HBsAg and anti-HBc IgG indicates persistent chronic HBV infection
- Hepatitis Be antigen (HBeAg): Marker of active current infection (correlates with a high level of viral replication and is also called a ‘marker of infectivity’
- Hepatitis Be antibody (anti-HBe): Marker of inactive virus (correlates with low rates of viral replication)
- HBV DNA: Measures virus activity (correlates with active replication) and is useful in monitoring response to treatment of HBV infection.