Prophylaxis of pneumococcal infection in sickle-cell disease by the combined use of vaccination and penicillin

Forty children homozygotes for sickle-cell disease (SCD) aged 2-5 years were enrolled in a study to assess the efficacy of pneumococcal vaccine combined with penicillin prophylaxis in preventing pneumococcal infection. The vaccine was given initially and then every 2 years as a booster. In addition to pneumococcal vaccine, 24 children were prescribed penicillin-V orally twice daily while the remaining 16 were given benzathine penicillin intramuscularly every 4 weeks in the clinic. The study period lasted for 4 years during which the clinic attendance rate of both groups was 90% and 92% respectively. The compliance with oral penicillin intake was checked by random urine testing for penicillin. The test was positive in 128 out of 320 urine samples (40%). The parenteral penicillin was given at every clinic visit and the rate of compliance was 92%. Twelve episodes of bacterial sepsis were documented: 10 of them were caused by Gram-negative organisms. The pneumococcus caused a fatal episode of septicaemia and meningitis in a child who did not comply with penicillin prophylaxis. In a retrospective search, 15 episodes of bacterial sepsis have been documented in 22 children receiving no prophylaxis for 2 years. Eight of those episodes were caused by the pneumococcus. The combination of pneumococcal vaccine with penicillin prophylaxis was effective in preventing pneumococcal sepsis in children with SCD followed up for 153 patients years.