Background:  Evolution of hepatitis B virus (HBV) serological markers has rarely been investigated among HIV-infected patients receiving HAART.

Methods:  Between 1997 and 2002, 633 patients (598 males; median age, 34 years; median CD4 count, 132 x10⁶/L; HIV RNA load, 5.01 log₁₀ copies/mL) were tested for HBV serological markers at baseline—including HBs antigen (HBsAg), anti-HBs antibody, and anti-HBc—and for anti-hepatitis C virus (HCV) antibody, HCV RNA, and HBV DNA, all of which were re-tested at intervals of ≥1 year. Medical records were reviewed to identify clinical characteristics associated with evolution of serological markers. Patients receiving HBV vaccine were excluded from analysis. None of the patients were receiving tenofovir, adefovir, or entecavir.

Results:  After a follow-up duration of 5.1 years (range 1.0 to 7.9 years) and HAART for 5.0 years (range 1.0 to 7.9 years), which contained lamivudine for 4.45 years (range, 1.0 to 7.9), 161 (25.4%) patients had changes of HBV markers. Of 119 (18.8%) patients with HBsAg at baseline (67.2% HBV DNA detectable), 6 (5.0%) developed anti-HBs (seroconversion rate, 2.57 per 100 person-years) and 9 (7.6%) isolated anti-HBc. Of 270 (42.7%) patients with anti-HBs, 18 (6.7%) lost anti-HBs. Of 179 (28.3%) patients with isolated anti-HBc (7.3% HBV DNA detectable), 81 (45.3%) had persistence of isolated anti-HBc, 73 (40.8%) developed anti-HBs, 18 (10.1%) lost all HBV markers, and 7 (3.9%) developed HBsAg. Of 65 (10.3%) patients without any HBV markers, 13 (20%) developed anti-HBs, 13 (20%) isolated anti-HBc, and 4 (6.2%) HBsAg (new HBV infection rate, 9.31 per 100 person-years). Patients with isolated anti-HBc at baseline were more likely to have AIDS (p = 0.008). In multivariate analysis, only increase of CD4 count after HAART was significantly associated with persistence of and subsequent development of anti-HBs in patients with anti-HBs and isolated anti-HBc at baseline, respectively.

Conclusions:  Periodic measurements of HBV serological markers in HIV-infected patients should be considered because changes of HBV serological markers are not uncommon after HAART. Development of anti-HBs was associated with immune reconstitution in patients with isolated anti-HBc antibody.