Equal IgG antibody response to pneumococcal vaccination in all stages of human immunodeficiency virus disease

To evaluate the immunogenicity and safety of a 23-valent pneumococcal vaccine in human immunodeficiency virus (HIV)-seropositive patients, 80 men and 18 women received 1 dose of the vaccine (Pneumo 23; Pasteur Mérieux MSD, Brussels). The total IgG antibody response against all 23 Streptococcus pneumoniae capsular antigens was measured. Antibody levels were expressed in arbitrary units per microliter, referring to a standard curve. Geometric mean titers of the total IgG capsular antibodies on the day of vaccination and 30–45 days later were compared. The ratios of titers after and before vaccination in patients with >500,200–500, and <200 CD4 1ymphocytes/µL were 10, 10, and 12.6, respectively. Nonresponse (ratio <4) occurred in 17% of patients and was unrelated to CD4 cell count. The vaccine was well tolerated; no serious side effects occurred. In 83% of the patients with HIV infection, the total antipneumococcal IgG level was higher after vaccination.