Abstract: TH-PO907
Extreme Duration of Positive Hepatitis B Surface Antigen (HBsAg) after Vaccination in a Hemodialysis Patient
Session Information
- Dialysis: Infection
November 02, 2017 | Location: Hall H, Morial Convention Center
Abstract Time: 10:00 AM - 10:00 AM
Category: Dialysis
- 610 Dialysis: Infection
Authors
- Barth, Robert H., VA NY Harbor Healthcare System, Brooklyn, New York, United States
- Patel, Amar V., SUNY Downstate College of Medicine, Brooklyn, New York, United States
Background
Patients with end stage renal disease (ESRD) without immunity to hepatitis B virus (HBV) frequently receive vaccines containing purified non-infectious subunits of HBsAg. The two vaccines available in the U.S., Engerix-B (ENG) and Recombivax HB (REC), are both produced by cloning HBV DNA into the yeast Saccharomyces cerevisae and harvesting and purifying the resultant HBsAg expressed by the yeast. There have been many reports of transient positivity of HBsAg assays in patients who have received these vaccines, almost always lasting less than 14 days, with several case reports of HBsAg positivity of 28 to 48 days’ duration.
Methods
We report a case of extremely long-term HBsAg positivity apparently induced by vaccination. The patient was a man with ESRD secondary to diabetes. After beginning hemodialysis he received 3 doses of ENG in 2003-2004, and within one month developed a positive assay for antibodies (Ab) to HBV (HBsAb). HBsAg was never positive, but the assays were obtained 15-40 days after the vaccinations. He continued to have positive assays for HBsAb for 33 months, after which the Ab gradually became undetectable, and in 2007 a new series of vaccinations, this time with REC, was begun. 30 days after the first vaccination HBsAg and HBsAb had simultaneously become weakly positive, and 32 days after the second dose both antigen (Ag) and Ab assays were fully positive. The patient was clinically stable, LFTs were entirely normal, and HBV DNA, core antibody, e antibody and e antigen were repeatedly negative. No further vaccinations were given. Concurrent HBsAg and HBsAb positivity persisted for 4.3 years, with reduction of HBsAg titers after 1.5 years, but with weak positivity persisting until the patient’s death from an unrelated cause in 2011.
Conclusion
The mechanism for this persistent Ag positivity is not clear, but was almost certainly not active HBV infection, and was temporally very closely correlated with REC vaccination. The sequential use of two different vaccines may have played a role through differences in their antigenic structure, but this is not certain. Explanation of this phenomenon will require further study, but this case illustrates the extreme variability of HBV Ag/Ab assay results after HBV vaccination in patients on hemodialysis.