Serum antibody responses of high-risk children and adults to vaccination with capsular polysaccharides of Streptococcus pneumoniae.

Pneumococcal antibody was measured in the sera of splenectomized children, children with neprotic syndrome, adult with chronic renal failure, adults maintained on hemodialysis, adult recipients of renal allografts, and normal children and adults before and after vaccination with a polyvalent vaccine against Streptococcus pneumoniae. The medical conditions of these patients are associated with increased morbidity and mortality due to pneumococcal disease. Nonimmunosuppressed splenectomized children, children with steroid-responsive nephrotic syndrome, and adults maintained on hemodialysis had normal concentrations of antibody in serum and normal antibody responses to pneumococcal vaccine. Children with steroid-resistant nephrotic syndrome and adult recipients of renal allografts had low concentrations of antibody in serum before and after vaccination but showed an antibody increase after vaccination. During the first year after vaccination of the splenectomized patients, serum antibody concentrations declined linearly by 24%-32% from the peak antibody level. These results suggest that immunization with pneumococcal polysaccharides may reduce the indicence of pneumococcal disease in some high-risk patients but not in others.