The immunogenicity of pneumococcal conjugate vaccinations in patients with asplenia and hyposplenia: a systematic review.

Pneumococcal conjugate vaccines (PCVs) are important preventive tools against invasive pneumococcal disease (IPD) in asplenic patients. This systematic review assesses current data and knowledge gaps on the immunogenicity of PCVs in asplenic patients. Twenty-seven studies were included assessing post-PCV IgG, opsonophagocytic functionality (OPA), or B-cell responses. We show that PCVs induce a strong serotype-specific IgG and OPA response in asplenic adults and children with various underlying conditions. Data in this review suggest that PPV23 has limited benefits for adults, but has been shown to broaden and boost the vaccine response in children with sickle cell disease. Moreover, we detected a lack of data on B-cell responses post-PCV and the optimal timing for vaccination around splenectomy. In conclusion, administration of PCVs in asplenic patients is supported by this review. The role of PPV23 in asplenic adults is probably limited, which supports the expected replacement of PPV23 by higher valent PCVs.