Pneumococcal vaccination for splenectomized patients with thalassemia major in Indonesia

Introduction Streptococcus pneumoniae is a capsulated bacterium that can cause severe infection in patients with thalassemia major, particularly those who have undergone splenectomy. The absence of the spleen as well as zinc deficiency in splenectomized patients with thalassemia major increases the possibility of developing invasive pneumococcal infection. The aims of this study are to evaluate pneumococcal IgG levels following PCV and PPV immunizations and the effect of zinc supplementation on qualitative specific immune responses in splenectomized patients with thalassemia. Methods Splenectomized patients with thalassemia major were administered a PCV pneumococcal vaccine (Prevenar 13®) at the start of the trial, after which they were randomly assigned to 2 groups (zinc and placebo group). After 8 weeks, the patients received a PPV pneumococcal vaccine (Pneumovax®). Zinc syrup was provided to the zinc group at a dose of 1.5 mg/kg/day (maximum of 50 mg/day). Pneumococcal IgG examinations were conducted at the start of the trial and after 12 weeks. Results In the group without PPV, the median initial pneumococcal IgG value was 315 (ranging from 65 to 1419) mU/mL for the zinc group and 338.5 (ranging from 82 to 1648) mU/mL for the placebo group. The median final pneumococcal IgG value was 1812.5 (ranging from 834 to 2444) mU/mL for the zinc group and 2857.5 (ranging from 834 to 2624) for the placebo group. The increase in the pneumococcal IgG value between the two groups was comparable (p = 0.642). In the group with previous PPV, the median initial pneumococcal IgG value was 1333 (ranging from 793 to 2031) mU/mL for the zinc group and 880 (ranging from 74 to 1686) mU/mL for the placebo group. The median final pneumococcal IgG value was 1487 (ranging from 635 to 1757) mU/mL for the zinc group and 1012 (ranging from 292 to 1732) mU/mL for the placebo group. The increase in the pneumococcal IgG value between the two groups was comparable (p = 0.528). Conclusion There is no difference in the increase in pneumococcal IgG level in splenectomized patients with thalassemia major prior to and after receiving PPV. There were no differences observed in the development of pneumococcal IgG following zinc supplementation.