title: Occult hepatitis B virus infection in patients with isolated core antibody and HIV co-infection in an urban clinic in Johannesburg, South Africa.
abstract: BACKGROUND
  The prevalence of HIV/hepatitis B virus (HBV) co-infection in South Africa ranges from 4.8% to 17% using the standard marker surface antigen (hepatitis B surface antigen, HBsAg) for chronic active HBV infection. However, sensitive molecular techniques for detecting HBV DNA in serum can detect occult HBV infection. We report the first observational prospective study of occult HBV infection in HIV-positive people in South Africa.
  
  
  METHODS
  Five hundred and two patients attending an urban hospital were screened for HBV using serological testing for HBsAg, core antibody (anti-HBc), and surface antibody (anti-HBs). DNA was analyzed using real-time quantitative PCR to determine the HBV viral load.
  
  
  RESULTS
  Of the 502 participants, 24 (4.8%) were HBsAg-positive and 53 (10.6%) were positive for anti-HBc alone. Of these 53, screening for occult disease was carried out in 43, of whom 38 (88.4%) were positive. The mean HBV viral load was 2.8 x 10(4) copies/ml (range 1 x 10(2) to 1 x 10(6) copies/ml).
  
  
  CONCLUSIONS
  Combining the participants with positive HBsAg and occult HBV DNA results, the prevalence of HBV increases from 4.8% (HBsAg alone) to 12.4%. While the clinical impact of occult HBV infection is unclear, consideration should be given to changing the guidelines to recommend dual HBV therapy for the treatment of co-infected patients in the developing world.
authors.affiliation: Clinical HIV Research Unit, Department of Medicine, University of the Witwatersrand, Johannesburg, South Africa. cfirnhaber@witshealth.co.za
authors.forename: Cynthia
authors.initials: C
authors.lastname: Firnhaber
authors.forename: Raquel
authors.initials: R
authors.lastname: Viana
authors.forename: Anne
authors.initials: A
authors.lastname: Reyneke
authors.forename: Doreen
authors.initials: D
authors.lastname: Schultze
authors.forename: Babatyi
authors.initials: B
authors.lastname: Malope
authors.forename: Mhairi
authors.initials: M
authors.lastname: Maskew
authors.forename: Adrian
authors.initials: A
authors.lastname: Di Bisceglie
authors.forename: Patrick
authors.initials: P
authors.lastname: MacPhail
authors.forename: Ian
authors.initials: I
authors.lastname: Sanne
authors.forename: Michael
authors.initials: M
authors.lastname: Kew
mesh_terms: D000914:Antibodies, Viral / Q000097:blood*; D004279:DNA, Viral / Q000097:blood / Q000378:metabolism; D015658:HIV Infections / Q000150:complications* / Q000453:epidemiology; D006509:Hepatitis B / Q000097:blood / Q000150:complications* / Q000453:epidemiology / Q000276:immunology; D006514:Hepatitis B Surface Antigens / Q000097:blood*; D006801:Humans; D008099:Liver / Q000821:virology; D015995:Prevalence; D012680:Sensitivity and Specificity; D013019:South Africa / Q000453:epidemiology; D014505:Urban Population; D019562:Viral Load
chemical_list: D000914:Antibodies, Viral; D004279:DNA, Viral; D006514:Hepatitis B Surface Antigens