Educational draft · awaiting clinical reviewUse Rapid for revision, not patient-care decisions. Check current national and local guidance and the BNF or BNFC before acting.
2 min synopsisUK scopeSources checked 27 Aug 2026Clinical review pending
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Escalate
Acute jaundice with encephalopathy, hypoglycaemia or increasing INR needs urgent liver-centre discussion regardless of whether HBV serology is complete. Severe hepatitis during pregnancy, immunosuppressive therapy or after withdrawal of HBV-active antiviral treatment also needs same-day specialist review. Draw virological samples promptly, but do not delay stabilisation, acute liver failure care or management of sepsis and bleeding while waiting for HBsAg, anti-HBc IgM or HBV DNA.
Synopsis
Interpret hepatitis B markers as a coherent pattern, distinguish current, resolved and vaccine-derived states, and anticipate chronic disease, reactivation and transmission risk.
HBsAg indicates current HBV infection; persistence for at least six months supports chronic infection rather than a single acute snapshot.
Total anti-HBc marks natural exposure and is not produced by vaccination, while anti-HBs indicates immunity from recovery or successful vaccination.
HBsAg-negative, anti-HBc-negative, anti-HBs-positive is the typical vaccine-derived pattern when the history fits.
Key red flags
Acute liver failure
Confusion, hypoglycaemia and increasing INR during acute HBV indicate failing hepatic function and require immediate regional transplant-centre involvement.
Investigation priorities
01
HBsAg with confirmatory testingFirst step
Establish current surface-antigen positivity and avoid acting on analytical false reactivity.
Management branches
DecodeRead the marker pattern
HBV screening returns one or more reactive antigen or antibody results.
Confirm HBsAg reactivity through the laboratory algorithm, assemble HBsAg, total anti-HBc and anti-HBs together, and retrieve vaccination and previous testing history.
Use IgM anti-HBc, HBeAg, anti-HBe and HBV DNA to answer specific timing and replication questions rather than attaching a phase from a single marker.
National guidance is shown before implementation-dependent detail. Typical adult dose examples remain subject to patient factors, contraindications and the live BNF or specialist protocol. Source check completed 27 Aug 2026; clinical approval remains outstanding.