The Hepatitis B Core Antibody IgM (Anti-HBc IgM) test detects IgM antibodies against the Hepatitis B Core Antigen (HBcAg). The presence of Anti-HBc IgM indicates an acute or recent infection with the Hepatitis B virus (HBV). It is the first antibody to appear after infection and typically fades as the body clears the virus or enters the chronic phase.
✅ Detects Acute Hepatitis B Infection – The presence of Anti-HBc IgM typically indicates recent infection or an acute flare-up of chronic HBV infection.
✅ Differentiates Between Acute and Chronic HBV – Helps distinguish between newly acquired HBV infection and chronic infection.
✅ Guides Treatment Decisions – Identifying acute infection can prompt early antiviral therapy or monitoring.
✅ Helps in the Diagnosis of Hepatitis B Reactivation – Useful for individuals with chronic HBV who experience a flare-up of liver disease.
🩸 Blood Sample Collection – A blood sample is taken and tested using ELISA (Enzyme-Linked Immunosorbent Assay) or Chemiluminescent Immunoassay (CLIA) to detect the presence of IgM antibodies.
| Anti-HBc IgM Result | Interpretation | Next Steps |
|---|---|---|
| Positive (Detected) | Acute or recent Hepatitis B infection | Perform HBV DNA PCR, Liver Function Tests (LFTs), and other markers (HBsAg, Anti-HBe). |
| Negative (Not Detected) | No acute HBV infection | Consider chronic HBV infection, past exposure, or immunity from vaccination. |
📌 A positive Anti-HBc IgM result indicates acute hepatitis B, often in the first 6 months of infection.
| HBV Infection Stage | HBsAg | Anti-HBc IgM | Anti-HBc Total | Anti-HBs | HBV DNA |
|---|---|---|---|---|---|
| Acute HBV Infection | Positive | Positive | Positive | Negative | High |
| Chronic HBV Infection | Positive | Negative | Positive | Negative | High/Variable |
| Recovered from HBV | Negative | Negative | Positive | Positive | Undetectable |
| Vaccinated | Negative | Negative | Negative | Positive | Undetectable |
📌 Anti-HBc IgM is typically negative in chronic infection or past exposure and helps rule out chronicity.
✔ Individuals with recent symptoms of hepatitis (jaundice, fatigue, abdominal pain), especially if there’s a known exposure to HBV.
✔ Patients with a history of chronic HBV who experience an acute liver flare-up or reactivation.
✔ Healthcare workers or individuals at high risk for HBV exposure who are symptomatic.
✔ Pregnant women to assess the stage of HBV infection and prevent transmission to the baby.
✔ Blood and organ donors to prevent HBV transmission.
✔ Anti-HBc IgM is the marker for acute or recent HBV infection and is the first antibody to appear during infection.
✔ A positive result indicates active viral replication and ongoing infection, necessitating further testing (like HBV DNA PCR, Liver Function Tests).
✔ A negative result rules out acute infection but does not exclude chronic infection, past exposure, or vaccination.
✔ Prompt detection of acute HBV can guide appropriate treatment and prevent complications.