Hepatitis B core IgM antibodies begin to appear in your blood several weeks after you are first infected with HBV. People who have had the hepatitis B vaccine will not have the core antibody in their blood. HBV is 1 of 5 hepatitis viruses. The others are hepatitis A, C, D, and E. Most hepatitis infections are caused by these 5 viruses.

Positivity indicates recent infection with hepatitis B virus (<6 mos). Its presence indicates acute infection. IgM anti-HBc should be ordered only when acute HBV infection is a concern.

A negative result of <0.90 indicates that IgM anti-HBc antibodies were not detected.A positive result of >1.10 indicates presumptive evidence of hepatitis B virus infection

The Hepatitis B Core IgM Antibody (Anti-HBc IgM) test is used to detect IgM antibodies against the Hepatitis B core antigen (HBcAg) in the blood. Here's how to interpret the test results: Positive Result: A positive Anti-HBc IgM result indicates the presence of IgM antibodies against HBcAg in the blood. Interpretation: Anti-HBc IgM positivity suggests recent or acute Hepatitis B virus (HBV) infection. In acute HBV infection, IgM antibodies against HBcAg typically appear early during the acute phase of infection and may precede the onset of symptoms. Anti-HBc IgM positivity is often associated with active viral replication and high levels of HBV DNA in the blood. Acute HBV infection may present with symptoms such as jaundice, fatigue, abdominal pain, nausea, vomiting, and fever. In some cases, Anti-HBc IgM positivity may persist for several months after acute infection, especially in individuals with delayed seroconversion to Anti-HBc IgG antibodies. Negative Result: A negative Anti-HBc IgM result indicates the absence of detectable IgM antibodies against HBcAg in the blood. Interpretation: A negative result suggests the absence of recent or acute HBV infection. It may occur in individuals with resolved acute HBV infection, where IgM antibodies against HBcAg have declined, and IgG antibodies against HBcAg have developed. It may also occur in individuals with chronic HBV infection or remote HBV infection, where Anti-HBc IgG antibodies are present, but IgM antibodies against HBcAg are no longer detectable. Clinical Correlation: Interpretation of Anti-HBc IgM test results should be done in conjunction with other HBV serological markers, including HBsAg, Anti-HBs, and total Anti-HBc. Additional tests, such as HBV DNA quantification and liver function tests, may be necessary to assess the stage and activity of HBV infection. Timing of Testing: Anti-HBc IgM antibodies are typically detectable during the acute phase of HBV infection and may decline over time as the infection resolves. Testing for Anti-HBc IgM should be performed within the appropriate window period during the acute phase of infection to maximize sensitivity. Limitations: False-positive results may occur due to cross-reactivity with antibodies against other viruses or nonspecific immune responses. False-negative results may occur if the test is performed outside the window period when IgM antibodies against HBcAg are detectable. Interpretation of Anti-HBc IgM test results should be performed by healthcare providers experienced in the diagnosis and management of HBV infection. It's essential to consider the patient's clinical history, symptoms, risk factors for HBV exposure, and other relevant factors when interpreting these results and determining the appropriate diagnosis and management plan. Confirmation of diagnosis may require additional testing and clinical evaluation.

Blood