Influence
of Occult Hepatitis B Virus on Liver Disease Progression and Response to Interferon-based
Therapy in HIV-HCV Coinfected Patients By
Liz Highleyman  Occult
or "hidden" hepatitis B virus (HBV) infection refers to detectable serum
HBV core antibodies (HBcAb) and viral genetic material (HBV DNA), but an absence
of HBV surface antigen (HBsAg).
Prior
research has shown that occult HBV infection is common among HIV
positive individuals, including those with HIV-HCV coinfection. However, its
clinical significance is not well understood.
In a study reported in the
April 2008 issue of AIDS Research and Human Retroviruses, Spanish investigators
evaluated the prevalence of occult hepatitis B in HIV-HCV
coinfected patients and its clinical relevance in terms of liver histology
and virological response to interferon-based
therapy for hepatitis C.
The study included 238 HIV-HCV coinfected
participants who tested negative for HBsAg. Serum samples were analyzed for the
presence of HBV DNA and HBcAb. HBV DNA quantification was determined using the
Cobas TaqMan HBV assay with a limit of detection of 6 IU/ml. Data from liver biopsies
and laboratory tests were also analyzed.
Results
| •
| 142 participants
(60%) were found to have detectable HBcAb. | | •
| Independent
factors associated with HBcAb positivity were male sex, age, previous history
of injection drug use, CD4 cell count, and the presence of hepatitis A virus (HAV)
antibodies. | | •
| Among
90 HBcAb positive patients with samples that could be analyzed, 15 also had detectable
HBV DNA. | | • | This
rate of occult HBV represented 16.7% of the HBcAb positive group and 6.3% of the
entire HIV-HCV coinfected cohort. | | • | No
baseline factors, liver histology findings, or factors related to hepatitis C
treatment response were significantly associated with detectable HBV DNA. |
"We
found that occult hepatitis B is a frequent condition present in at least 6.3%
of our HCV-HIV patients and in more than 16% of those with HBcAb," the study
authors concluded.
Despite this high prevalence, however, they added that,
"this phenomenon does not seem to affect the clinical evolution of chronic
hepatitis C or modify the viral response to interferon-based HCV therapies."
6/10/08
Reference
M
Laguno, M Larrousse, JL Blanco, and others. Prevalence and clinical relevance
of occult hepatitis B in the fibrosis progression and antiviral response to INF
therapy in HIV-HCV-coinfected patients. AIDS Research and Human Retroviruses
24(4): 547-553. April 2008.
|
