1038
Occult Hepatitis B Virus Infection in HIV Patients in an Urban Clinic in Johannesburg, South Africa
Cynthia Firnhaber*1, R Viana2, A Reyneke1, D Schultz1, B Malope1, P Macphail1, I Sanne1, A Di Bisceglie3, and M Kew2
1Univ of the Witwatersrand, Johannesburg, South Africa; 2Univ of the Witwatersrand, Johannesburg, South Africa; and 3Univ of St Louis, MO, US
Background: Both HIV and hepatitis B virus (HBV) infections
are endemic in Sub-Saharan Africa. Recent studies using hepatitis B surface
antigen (HBsAg) as the standard marker for chronic active HBV infection, have
shown the prevalence of HIV/HBV co-infection in South Africa range from 4.8 to 17%.
However, using more sensitive molecular techniques for detecting HBV DNA in
serum, occult HBV infection has emerged as an important entity. We report the
first observational prospective study of occult HBV infection in HIV seropositive
people in South Africa.
Methods: The patients were invited and consented from the
Themba Lethu Clinic Cohort, at the Helen Joseph Hospital in South Africa. We screened 502 patients for HBV using serology including HBsAg, core antibody,
and surface antibody. DNA was analyzed by quantitative real-time polymerase
chain reaction (RT-PCR) using the ABI Prism 7500 to determine the HBV viral
load. PCR primers HBV-Taq1 and HBV-Taq2, as well as the FAM/TAMRA-labeled
TaqMan BS-1 probe were used. A positive control from the National Institute for
Biological Standards was used, as well as to calibrate the standard curve. The
detection limit was found to be 10 IU/mL or 50 copies/mL. All isolates tested
for HBV DNA were tested for HCV RNA.
Results: Of the 502 patients screened, 4.8% were HBSAg
positive and 53 (10.6%) patients were positive for core antibody alone. Of the
53 samples, 45were screened for occult HBV DNA. The average CD4 count was 127cells/mm3
and a mean age of 37 of the participants which correlated with the larger
hepatitis B cohort: 29 female and 24 males had isolated hepatitis B core
antibody; 41 of 45 samples (91%) were positive for HBV DNA on RT-PCR. The mean
viral load was 2.8 x104 with a range was 1x102 to 1x106. Of 41 samples, 1
tested positive for HCV.
Conclusions: Isolated HBcAb positive serology is associated
with occult HBV infection (91% of sera tested) The chronic active HBV and
occult HBV co-infection rates in this subset of the Themba Lethu Cohort
increased from 4.8% using HBSAg alone to 13.0% using HBsAg and HBcAB combined. While
the clinical effect of occult HBV infection is currently unclear, recent
advances in Department of Health and Human Services (DHHS) guidelines
recommending dual therapy for co-infected patients may need to be considered in
our population. Combination therapy, including tenovofir/emitracibine or
lamivudine, may address the treatment requirement for our co-infected patients
in the developing world.
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