Does the 23-valent pneumococcal vaccine protect cochlear implant recipients?
OBJECTIVES/HYPOTHESIS: The incidence of meningitis is increased in cochlear implant (CI) recipients. Besides malformations, immunological deficiencies are predisposing factors. Therefore, the immunological background of CI recipients and the immunogenicity of the recommended 23-valent pneumococcal polysaccharide vaccine (PPV-23) were investigated. STUDY DESIGN: Prospective study in a tertiary care referral center. METHODS: One hundred twenty CI recipients who were at least 5 years of age were vaccinated with PPV-23. Levels of immunoglobulins G, A, and M (IgG, IgA, and IgM, respectively) and IgG subclasses IgG1-IgG4 before vaccination and serum concentrations of antibodies against seven pneumococcal serotypes before and 4 weeks after vaccination were determined. The cohort was subdivided by patient age into groups A1 (5-8 y), A2 (8-12 y), and A3 (>12 y). RESULTS: Geometric mean concentrations of pneumococcal antibodies before vaccination were remarkably low in all three groups, emphasiz
