HIV
Patients with Isolated Anti-HBc Antigen May Require HBV Vaccination
A
substantial number of HIV-infected individuals who test positive
for isolated antibody to hepatitis
B core antigen (anti-HBc) do not have an anamnestic
or rapid response to hepatitis B vaccine,
according to a new study.
"This
suggests that some of these subjects have not been previously
exposed to hepatitis B virus,
and that the positive test in these cases is a false positive
result," lead investigator Dr. Rajesh T. Gandhi from Massachusetts
General Hospital in Boston told Reuters Health.
"If
confirmed in larger studies, this finding would suggest that HIV-positive
subjects who test positive for isolated anti-HBc should receive
hepatitis B vaccination," Dr. Gandhi said.
It
is unclear, at present, whether HIV-infected patients who test
positive for anti-HBc should be vaccinated with hepatitis B vaccine,
Dr. Gandhi and colleagues note in the May 1st issue of The
Journal of Infectious Diseases.
They
assessed the anamnestic response rate in 69 HIV-infected subjects
who tested negative for hepatitis
B surface antigen (HBsAg) and antibody
to HBsAg (anti-HBs) and were immunized with hepatitis
B vaccine.
Twenty-nine
subjects (42%) tested positive for anti-HBc and 40 (58%) tested
negative for anti-HBc.
According
to the team, the overall rate of anamnestic response to hepatitis
B vaccination was low (16%) and did not differ significantly between
subjects who tested positive for anti-HBc (24%) and those who
tested negative for anti-HBc (10%) before vaccination.
This
suggests that testing for anti-HBc alone "may not be a reliable
assessment of protection from HBV infection," they contend.
An
"unexpected finding," according to the team, was that
HIV/HCV-coinfected subjects
were less likely to develop high anti-HBs titers after the third
vaccination than were those injected with HIV alone.
Further
study of the response to hepatitis B vaccination in larger groups
of HIV/HCV-coinfected individuals is warranted, they conclude.
05/11/05
J
Infect Dis 2005;191:1435-1441.
