Synopsis
Use a sexual-health visit to interpret HBV and HCV results accurately, act on recent exposure, prevent hepatitis B, identify current hepatitis C viraemia, and secure named linkage for liver assessment and treatment.
- HBV spreads efficiently through sexual and blood exposure; HCV is chiefly blood-borne, with sexual transmission concentrated where blood, mucosal trauma, injecting, HIV or ulcerative STI is present.
- Read HBV as a three-marker pattern: HBsAg indicates current infection, anti-HBc records natural exposure and anti-HBs indicates immunity; vaccination produces anti-HBs without anti-HBc.
- A reactive anti-HCV result records exposure, not current infection; reflex HCV RNA or a validated core-antigen route establishes active viraemia.
Key red flags
Jaundice with confusion, asterixis, bleeding, hypoglycaemia or deteriorating coagulation requires emergency liver-failure care.
HBsAg positivity in pregnancy needs prompt HBV DNA assessment and a documented plan for maternal care and neonatal immunoprophylaxis.
An infant born to an HBsAg-positive mother must receive hepatitis B vaccine within 24 hours and HBIG when the current national criteria apply.
Chemotherapy, major immunosuppression or B-cell-depleting treatment must not begin before HBsAg and anti-HBc results have been reviewed and reactivation prevention assigned.
A sudden ALT rise or jaundice in chronic HBV requires assessment for disease activity, reactivation, adherence, drug injury and hepatitis D.
A recent sexual, injecting, occupational or household blood exposure needs same-day assessment because hepatitis B vaccine and selected HBIG are time sensitive.
Thrombocytopenia, splenomegaly, spider naevi, ascites or abnormal synthetic function may reveal advanced HBV or HCV even after years of few symptoms.
Encephalopathy, coagulopathy, hypoglycaemia, bleeding or rapid multiorgan deterioration requires emergency liver and transplant-centre involvement.
Investigation priorities
Assign the patient to current HBV infection, resolved natural infection, vaccine immunity or susceptibility.
Management branches
The laboratory reports HBsAg positivity and reactive anti-HCV in the same asymptomatic patient.
- Complete the HBV marker panel, arrange HBV DNA and liver or fibrosis assessment, and refer current HBV through the named pathway.
- Reflex the anti-HCV sample to RNA because antibody cannot distinguish current infection from previous clearance or cure.