Q: Recently, I went for a HIV1/HIV2 EIA test. The results came as non-reactive. I was told I had Hepatitis B, but then when another blood test was done (to confirm) they said I did not have Hep B. Is it possible that a co-infection with Hep B and HIV would cause the EIA test to show a false result? Or would the antibody test still be conclusive?

A:You have not mentioned the details of your tests. The screening HBsAg test requires confirmation by a neutralisation assay if there is any discrepancy in clinical correlation. The hepatitis B virus (HBV) infection does not mask the HIV test results. However, due to overlapping routes of transmission, many HIV positive individuals have also been exposed to HBV. Studies suggest that as many as 70%-90% of HIV positive people have evidence of past or current HBV infection. Since a majority of patients spontaneously clear HBV without treatment, however, the rate of active infection is much lower. In the June 2007 issue of AIDS, French researchers reported data from a study assessing the characteristics of HBV infection in HIV positive patients and the impact of anti-HBV treatment in this population. The study included all patients with past or present HBV infection seen in October 2005 at 17 French hospitals. Data were retrospectively collected from the first visit in a time-dependent manner using a standardised questionnaire. • Among 477 HBV-infected patients, 261 (55%) were coinfected with HIV. • Coinfected patients were more likely to have initial detectable serum hepatitis B envelope antigen (HBeAg) (57.9% vs 28.6%). • Coinfected individuals were also more likely to have cirrhosis on their initial liver biopsy (17.9% vs 7.6%). • However, no significant differences in virological, immunological, or biochemical response were observed among these different treatments. In HBV-HIV coinfected patients, the assessment of HBV infection still needs to be improved, the HBV wild-type remains predominant, and HBeAg loss is rare and associated with a better histological evolution