The measurement of antibodies against the hepatitis B virus surface antigen (HBsAb) is used to determine possible previous exposure to the hepatitis B virus and to determine adequate immunity following hepatitis B vaccination.
Hepatitis B virus (HBV), has an incubation period of 6 to 23 weeks (mean 17 weeks). It is mainly transmitted by blood and certain secretions of the body. Hepatitis B can also be transmitted through the use of infected needles. This form of hepatitis is more severe than hepatitis A. It damages the liver cells and can lead to cirrhosis and liver cancer. The treatment involves the use of interferon and antiviral drugs in an attempt to control the virus's proliferation. Vaccination for HBV provides protection for over 20 years.
Hepatitis B virus consists of an outer shell that surrounds an inner "core". The outer shell contains a protein called hepatitis B surface antigen (HBsAg) or Australian antigen. The inner core contains the hepatitis B core antigen (HBcAg). The inner core also contains another protein called e (HBeAg) antigen. The human body reacts to the presence of these antigens by producing antibodies against them. Thus, laboratory testing includes tests for the presence of antigens as well as antibodies (HBsAb, HBcAb, and HBeAb).
Hepatitis B Surface Antibody (HBsAb, anti-HBs)
This test identifies antibodies against the hepatitis B surface antigen. This antibody appears 2 to 16 weeks after the hepatitis B surface antigen has disappeared. The presence of this antibody shows immunity to the hepatitis B virus, with the exception of some rare subtypes of the virus. This test is also used to determine if vaccination is necessary for persons at increased risk for hepatitis B. The positive result of the test shows immunity to hepatitis B from vaccination or recovery from infection.
Laboratory test results are the most important parameter for the diagnosis and monitoring of all pathological conditions. 70%-80% of diagnostic decisions are based on laboratory tests. The correct interpretation of laboratory results allows a doctor to distinguish "healthy" from "diseased".
Laboratory test results should not be interpreted from the numerical result of a single analysis. Test results should be interpreted in relation to each individual case and family history, clinical findings, and the results of other laboratory tests and information. Your personal physician should explain the importance of your test results.
At Diagnostiki Athinon we answer any questions you may have about the test you perform in our laboratory and we contact your doctor to get the best possible medical care.