Medical expert of the article
New publications
Hepatitis B test: IgM antibodies to HBcAg (Anti-HBcIgM) in blood
Last reviewed: 06.07.2025

All iLive content is medically reviewed or fact checked to ensure as much factual accuracy as possible.
We have strict sourcing guidelines and only link to reputable media sites, academic research institutions and, whenever possible, medically peer reviewed studies. Note that the numbers in parentheses ([1], [2], etc.) are clickable links to these studies.
If you feel that any of our content is inaccurate, out-of-date, or otherwise questionable, please select it and press Ctrl + Enter.
Anti-HB with IgM are normally absent in the blood serum.
Anti-HB c IgM are detected already at the beginning of the acute phase of the disease, even before the appearance or in the first days of jaundice, sometimes even at the end of the incubation period. Detection of anti-HB c IgM is a convincing criterion for diagnosing viral hepatitis B, especially with negative results of the study for HB with Ag. Anti-HB c IgM circulate in the blood of patients for several months (2-5 months) until the recovery period, and then disappear, which is considered a sign of cleansing the body of the viral hepatitis B virus.
Blood testing for the presence of anti-HB c IgM is performed for the following purposes:
- diagnostics of the acute period of viral hepatitis B;
- diagnostics of the convalescence period of viral hepatitis B;
- diagnostics of anti-HB s -positive chronic viral hepatitis B;
- diagnostics of chronic carriage of the hepatitis B virus.