Occult hepatitis B infection was present in 2% of HIV-positive individuals participating in two clinical trials in the USA in the mid-1990s according to a study published in the July 1st edition of the Journal of Acquired Immune Deficiency Syndromes. The study investigators recommend that patients who experience side-effects involving the liver after starting anti-HIV therapy should have occult hepatitis B infection ruled out by having a test for hepatitis B DNA should they test negative for hepatitis B antibodies but positive for hepatitis B core antigen (anticore).
A patient is said to have occult, or hidden, hepatitis B infection if they test positive for hepatitis B DNA and are positive for hepatitis B anticore but do not have the usual markers of hepatitis B infection: hepatitis B surface antigen and hepatitis B antibodies.
There are conflicting data on the prevalence and clinical significance of occult hepatitis B infection in HIV-positive individuals. Accordingly US investigators conducted a retrospective analysis using the stored plasma samples from 240 HAART-naïve HIV-positive individuals who participated in two clinical trials in 1996 and 1997. The investigators wished to establish the prevalence of current and past hepatitis B infection in these patients and the prevalence and significance of occult hepatitis B infection.
Stored plasma samples were tested for hepatitis B surface antigens, antibodies to hepatitis B and hepatitis B DNA. Serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels were measured to determine individuals’ liver function.
The study population was selected because it was geographically and demographically representative of the HIV infected population in the US. The median age of the study participants was 37 years, 50% were white, and 81% were male. Patients had a median CD4 cell count of 137 cells/mm3 and 40% of patients had an HIV viral load above 100,000 copies/ml.
A total of 64.6% of individuals had a marker of past or current infection with hepatitis B. Only 2.5% of patients had laboratory results suggesting vaccination against hepatitis B. Six patients tested positive for the hepatitis IgM antibody indicating acute infection.
A total of 7.5% of all patients tested positive for hepatitis B DNA. Over 80% of patients with hepatitis B DNA had either hepatitis B surface antigen or hepatitis B antibodies implying acute or chronic infection. However, 10% of patients without hepatitis B anticore (four individuals, 2% of entire study population) had detectable hepatitis B DNA which is suggestive of occult hepatitis B infection.
Levels of detectable hepatitis B DNA were similar between patients with chronic or acute infection and those individuals with occult hepatitis B infection. There were no significant differences in ALT or AST levels between patients with chronic and acute hepatitis B infection and individuals with occult hepatitis B.
The investigators recommend that “patients treated with HAART who exhibit serum transaminase abnormalities, hyperbilirubinemia, or liver failure should be tested for HBV markers, and if found to be positive for anti-HBc alone they should be further tested for HBV DNA.” They further recommend that a clinical trial be designed to guide the choice of specific anti-HIV drugs for individuals who are hepatitis B anticore positive.
Further information on this website
Hepatitis B - overview
Hepatitis B - factsheet
Few HIV-positive Americans vaccinated against HBV and 7% coinfected with HIV/HBV - news story
Occult HBV infection in HIV/HCV coinfected patients common - news story
Shire NJ et al. Occult hepatitis B in HIV-infected patients. Journal of Acquired Immune Deficiency Syndromes, 36: 869-875, 2004.