Ling R1, Ko H2, Greenleaf L2, Lindsay M2, Wignall A2, Gock H1,2,3
1Department of Nephrology, St Vincent’s Hospital Melbourne, Australia, 2Dialysis Unit , St Vincent’s Hospital Melbourne, Australia, 3University of Melbourne Department of Medicine, Melbourne, Australia
Aim: To examine the frequency of Hepatitis B DNA (HBV DNA) detection in dialysis patients who have demonstrable immunity.
Background: In-centre Haemodialysis(HD) patients with acute HBV infection indicated by HBsAg or HBeAg positivity are isolated for treatment sessions to reduce the risk of patient-machine-patient transmission. It is generally accepted that HBsAb persists lifelong in most patients after acute infection resulting in immunity. Concurrent HBsAb and HBcAb positivity suggests recovery from acute infection. The availability of HBV DNA detection by PCR now provides further confirmation of cleared virus following acute infection and development of immunity. We examined our in-centre HD population that have serological HBV immunity with HBV DNA PCR to ensure that immunity was effective in clearing virus.
Methods: HBV serology (HBcAb, HBsAb, HBsAg and HBV DNA) was collected from the past 12 months of in-centre maintenance HD patients at our institution (n=62). The presence of current acute HBV was noted.
Results: There were 16 patients that were HBsAb positive/HBcAb negative suggesting successful vaccination. None of those had detectable HBV DNA. There were 20 patients with HBcAb positivity and of those, 18 were HBV DNA PCR negative. Of the 2 HBcAb/HBV DNA positive cases, one had known current active infection and appropriately isolated. The other was also HBsAb positive, had low-level HBV PCR positivity and having HD with the general pool >10 years without transmission. Interestingly, 2 of 20 had isolated HBcAb positivity (ie. HBsAb negative), but neither were HBV DNA positive.
Conclusions: Low-level HBV DNA detection is possible but infrequent in patients with positive HBcAb and HBsAb. They are unlikely to be infectious but further studies are needed to determine infectious risks.
Rebecca Ling is a second year nephrology advanced trainee currently working at St. Vincent’s Hospital Melbourne, Victoria. She is passionate about research that is translatable to clinical practice.