Infecção oculta pelo vírus da hepatite B em pacientes infectados por HIV

Abstract

Hepatitis B virus (HBV) infection is a global health problem. It is estimated that two billion
people are infected with HBV around the world. Among them, it is possible that chronic infection
affects 240 million people and 780,000 die due this infection. Hepatitis B laboratory diagnosis is
accomplished by antigens and antibodies research in serum/plasma. Occult hepatites B is defined
like the presence of HBV DNA in the serum/plasma of individuals testing HBsAg negative, with
detectable or undetectable antibodies. Several studies report different values of prevalence of
HBV infection in HIV patients. HBV and HIV co-infections are common because of the same
transmission routes of both vírus. Occult hepatitis B is often described in HIV patients. The aim
of the study was to find HBV infection in in a group of HIV patients treated at SUS, identify
the occult hepatitis B virus infection and estimate the prevalence of HBV/HIV co-infections in
this group. The study included 232 patients with HIV, of which 202 on antiretroviral therapy and
30 treatment-naïve patients. Plasma samples were assayed for HBsAg, anti-HBs and anti-HBc
serological markers and Real Time PCR for detection and quantification of HBV-DNA. The
results indicated that 36.6% (85/232) of the patients had HBV exposure serological markers, of
which 11.8% (10/85) had HBsAg and/or HBV-DNA detected. These values characterize a HBV/
HIV co-infection prevalence of 4.3% (10/232) in this group. Among the no treated individuals,
10% (3/30) had occult HBV infecion due to detection of HBV-DNA in low concentrations and
HBsAg non-detected in their samples. Of all individuals, 34.5% (80/232) showed no serological
markers and were therefore suscepítveis to HBV infection. Anti-HBs alone was positive in 28.9%
(67/232) which features vaccination. The results indicated a high prevalence of hepatitis B in
HIV patients and also highlighted the importance of the association of laboratory techniques in
the diagnosis of hepatitis B. The Real Time PCR was an important tool in this study, because
through this technique was possible the knowledge of cases of hepatitis B not evidenced by
serology. The diagnosis of hepatitis B in HIV patients, especially the occult cases, may assist
in the administration of therapy if it is indicated, and identify potential transmitters of HBV not
detected in the most common laboratory tests. In these cases, the Real Time PCR as a diagnostic
tool, can support surveillance and thus, the control of transmission of HBV.