Mutations associated with occult hepatitis B in HIV-positive South Africans. J Med Virol 2015 Mar;87(3):388-400
Date
08/29/2014Pubmed ID
25164924Pubmed Central ID
PMC4562318DOI
10.1002/jmv.24057Scopus ID
2-s2.0-84921370324 (requires institutional sign-in at Scopus site) 20 CitationsAbstract
Occult hepatitis B is characterized by the absence of hepatitis B surface antigen (HBsAg) but the presence of HBV DNA. Because diagnosis of hepatitis B virus (HBV) typically includes HBsAg detection, occult HBV remains largely undiagnosed. Occult HBV is associated with increased risk of hepatocellular carcinoma, reactivation to chronic HBV during immune suppression, and transmission during blood transfusion and liver transplant. The mechanisms leading to occult HBV infection are unclear, although viral mutations are likely a significant factor. In this study, sera from 394 HIV-positive South Africans were tested for HBV DNA and HBsAg. For patients with detectable HBV DNA, the overlapping surface and polymerase open reading frames (ORFs) were sequenced. Occult-associated mutations-those mutations found exclusively in individuals with occult HBV infection but not in individuals with chronic HBV infection from the same cohort or GenBank references-were identified. Ninety patients (22.8%) had detectable HBV DNA. Of these, 37 had detectable HBsAg, while 53 lacked detectable surface antigen. The surface and polymerase ORFs were cloned successfully for 19 patients with chronic HBV and 30 patients with occult HBV. In total, 235 occult-associated mutations were identified. Ten occult-associated mutations were identified in more than one patient. Additionally, 15 amino acid positions had two distinct occult-associated mutations at the same residue. Occult-associated mutations were common and present in all regions of the surface and polymerase ORFs. Further study is underway to determine the effects of these mutations on viral replication and surface antigen expression in vitro.
Author List
Powell EA, Gededzha MP, Rentz M, Rakgole NJ, Selabe SG, Seleise TA, Mphahlele MJ, Blackard JTAuthor
Michael Rentz MD, MPH Assistant Professor in the Emergency Medicine department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
AdultDNA, Viral
Female
HIV Infections
Hepatitis B
Hepatitis B Surface Antigens
Hepatitis B virus
Humans
Male
Mutation, Missense
Sequence Analysis, DNA
South Africa
