Objectives: Pneumococcal infection is frequent and severe in patients with nephrotic syndrome (NS). Pneumococcal polysaccharide vaccine is recommended for nephrotic children older than 2 years of age. The aim of our study is to assess the clinical and laboratory efficiacy and side effects of pneumococcal polysaccharide vaccine in NS patients.
Methods: 27 children with steroid responsive NS and 20 controls were enrolled in the study. A 23 valent pneumococcal polysaccharide vaccine was used for vaccination. Blood samples were obtained before and 4 weeks and 3 years after vaccination. ELISA test was used to quantitate serum total antipneumococcal capsule polysaccharide immunoglobulin G antibodies. Antibody levels before vaccination, 4 weeks and 3 years after vaccination were compared.
Results: The mean age of the nephrotic children and controls were 7.8±3.1 years and 8.6±2.6 years, respectively. Baseline antibody titers and antibody titers following 4 weeks and 3 years of vaccination for nephrotic children and controls were 33.3±18 mg/L, 100.9±22.2 mg/L, 135.5±114.2 mg/L and 32.8±13 mg/L, 101.6±41.1 mg/L, 144.3± 64 mg/L, respectively. The increase in pneumococcal antibody levels in the 4th week (p<0.05) and the persistence of antibodies in the 3 year (p<0.05) were statistically significant and similar to the increases observed in the control group. 60% of the patients preserved their protective antibody levels at the 3rd year evaluation. None of the children showed neither side effects nor a pneumococcal infection episode during the study period.
Conclusion: We conclude that pneumococcal polysaccharide vaccine is a well tolerated and immunogenic vaccine in nephrotic children. Revaccination may be considered in nephrotic children after the assessment of antibody levels 3 years after vaccination.