Hepatitis B Virus Core Antibody

• Test samples as soon as possible after collecting. Testing may be performed on samples stored for up to 12 hours at room temperature for add on specimens.
• Store all samples at 2 – 8⁰ C for up to 3 days if testing can’t be done within 12 hours of collection.
• Freeze samples at or below -20⁰ C for longer storage. Frozen samples must be stored in a non-frost free freezer. Specimens may be frozen and thawed up to 2 times. Thoroughly mix thawed specimens and centrifuge at 10,000 X g for 10 minutes. Transfer the supernatant to a clean tube prior to testing.

Hepatitis B virus (HBV) is endemic throughout the world and is the major cause of liver disease. HBV is transmitted through direct contact with blood and body fluids. Common modes of transmission include blood transfusion, needle puncture, direct contact with open wounds, sexual contact, and mother-neonate contact during birth.

The average incubation period for HBV infection is 6 to 8 weeks (range 1 to 6 months). Common clinical symptoms include malaise, fever, gastroenteritis, and icterus. HBV infection can result in typical icteric hepatitis, subclinical anicteric hepatitis, fulminant hepatitis, or chronic or persistent hepatitis. In adults, 90 to 95% of patients with HBV infection completely recover from acute illness and clear the virus. Approximately 5 to 10% of patients with HBV become chronic carriers. In HBV infected neonates, approximately 90% develop chronic hepatitis B infection. It is estimated that over 300 million people worldwide are chronic carriers of the virus.

HBV infection, particularly in cases of chronic infection, is clearly associated with the development of hepatocellular carcinoma. Hepatitis B core antigen (HBcAg), found in liver cells, does not circulate in the bloodstream. However, IgM and IgG antibodies to HBcAg can be detected serologically in HBV infected individuals. Anti-HBc IgM is detectable first and remains detectable for approximately 6 months. Shortly after the IgM response, anti-HBc IgG appears and can remain detectable indefinitely. The presence of anti-HBc IgM and anti-HBc IgG is characteristic of acute infection, while the presence of anti-HBc IgG without anti-HBc IgM is characteristic of chronic or recovered stages of HBV infection. Anti-HBc Total assays detect both IgM and IgG anti-HBc responses. Most often levels of anti-HBc will coincide with detectable levels of other HBV markers. Rarely, anti-HBc may be the only detectable HBV marker. This may occur during the brief period when hepatitis B surface antigen has been cleared from the bloodstream and before antibodies to hepatitis B surface antigen become detectable. For this reason, the use of anti-HBc Total assays to detect acute infection is not recommended. Anti-HBc Total assays should be used in conjunction with other marker assays to assess current or past exposure to HBV.