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Limited infection with occult hepatitis B virus in drug users in the USA
Jason T Blackard1, Christina M Martin, Satarupa Sengupta
1Division of Digestive Diseases, University of Cincinnati College of Medicine, Cincinnati, Ohio Department of Public Health and Community Medicine, Tufts University School of Medicine, Boston, Massachusetts, USA.
Aim:
Occult HBV infection (O-HBV) is defined as low level HBV replication in the absence of detectable circulating HBV surface antigen. O-HBV has been implicated in HBV reactivation, advanced liver fibrosis and cirrhosis, reduced interferon response rates, elevated liver enzyme levels, and the development of hepatocellular carcinoma. However, the prevalence of O-HBV has not been clearly established in certain at-risk populations, such as injection drug users.
Methods:
Therefore, the current pilot study examined the prevalence of O-HBV in a prospective cohort designed to assess the role of injection and non-injection drug use (IDU) on HIV-associated comorbidities.
Results:
Utilizing two distinct real-time polymerase chain reaction assays, HBV DNA was not detected in 99 participants examined.
Conclusion:
This finding is in contrast to other data from US IDU cohorts and suggests that the prevalence of O-HBV infection is very specific to the cohort studied, is sensitive to other confounding variables such as hepatitis C virus and/or HIV serostatus, and should not be generalized across risk groups or distinct cohorts.
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