Hepatitis B screening
Hepatitis B surface antigen, HBsAg
When to request this test
- All pregnant women during antenatal care to prevent mother-to-child transmission
- All infants born to HBV-positive mothers to evaluate vertical transmission
- Household members and close contacts of individuals with chronic HBV infection
- Patients with elevated liver enzymes of unknown cause
- Individuals before initiating immunosuppressive or chemotherapy treatments to prevent HBV reactivation
- Consider universal screening in adults in regions with ≥2% HBsAg prevalence
Interferences & limitations
- False positive results: cross-reactivity with other antigens, autoimmune diseases
- False negative results: low viral load, certain mutations (e.g., affecting the HBV S region)
1 day
- Sample nature: Blood (serum or plasma)
- Recommended volume: 2 mL
- Type of container: Serum tube, serum separation tube (SST)
<12h at room temperature