Hepatitis B Laboratory Testing for Dialysis Patients
For dialysis patients, hepatitis B screening should include testing for HBsAg, anti-HBs, and anti-HBc before admission to an outpatient dialysis facility. 1 This comprehensive panel is essential for determining infection status, immunity, and guiding appropriate management to prevent transmission in the dialysis unit.
Required Initial HBV Testing
- HBsAg (Hepatitis B surface antigen): Detects active infection
- Anti-HBs (Antibody to HBsAg): Determines immunity status
- Anti-HBc (Antibody to hepatitis B core antigen): Identifies previous exposure
This three-test panel is specifically recommended by both the CDC and the American Association for the Study of Liver Diseases for all dialysis patients 1.
Interpretation of Results and Follow-up Testing
| Test Results | Interpretation | Follow-up Testing |
|---|---|---|
| HBsAg(-), anti-HBs(-), anti-HBc(-) | Susceptible to HBV | Monthly HBsAg screening; Vaccinate |
| HBsAg(-), anti-HBs(+), anti-HBc(-) | Immune due to vaccination | Annual anti-HBs testing |
| HBsAg(-), anti-HBs(+), anti-HBc(+) | Immune due to resolved infection | No further testing required |
| HBsAg(+), anti-HBs(-), anti-HBc(+) | Chronic infection | Isolation; Consider treatment |
Ongoing Monitoring Requirements
- Susceptible patients: Monthly HBsAg testing to detect seroconversion early 1
- Vaccinated patients: Annual anti-HBs testing; revaccinate if levels drop below 10 IU/mL 1
- HBsAg-positive patients: Consider HBV DNA testing to assess viral load and infectivity 2
Common Pitfalls to Avoid
Incomplete testing: Testing only HBsAg and anti-HBc is insufficient as it doesn't determine vaccination needs 1
Missing the window period: Testing only HBsAg and anti-HBs could miss acute infection in the window period when HBsAg has cleared but anti-HBs hasn't developed 1
False-negative HBsAg: Rare cases of high HBV DNA with negative HBsAg have been reported in dialysis patients 3, highlighting the importance of the complete panel
Delayed vaccination: Patients should be vaccinated if susceptible, with higher doses recommended for dialysis patients (40 μg at 0,1,2, and 6 months for Engerix-B or 40 μg at 0,1, and 6 months for Recombivax HB) 1
Additional Recommended Testing
- HCV antibody: Screen at dialysis initiation and then every 6 months (KDIGO grade 1A/1B recommendation) 1
- HIV antibody: Recommended for patients ages 13-64 years (with informed consent) 1
- Tuberculosis: Either tuberculin skin test or IGRA blood test 1
By following these comprehensive testing protocols, dialysis facilities can significantly reduce the risk of HBV transmission, which has become rare in U.S. dialysis clinics due to these vaccination, isolation, and infection-control practices 1.