COLONIZATION WITH ANTIBIOTIC-RESISTANT STREPTOCOCCUS-PNEUMONIAE IN CHILDREN WITH SICKLE-CELL DISEASE

Objective: Because of a susceptibility to severe pneumococcal infectio n, children with sickle cell disease (SCD) routinely receive penicilli n prophylaxis. Increasing rates of penicillin resistance have been rep orted throughout the world. Our objective was to assess the prevalence of nasopharyngeal colonization with Streptococcus pneumoniae and to a ssess the antimicrobial susceptibility of the organisms in children wi th SCD. Study design: Nasopharyngeal cultures for S. pneumoniae were o btained from all children with SCD attending clinics in a statewide un iversity-based network. Background colonization rates were determined in children attending day care centers in some of the same locations. All recovered S. pneumoniae organisms were tested for susceptibility t o penicillin, and all resistant strains were examined for susceptibili ty to other antibiotics. Results: Overall nasopharyngeal pneumococcal colonization rates among children with SCD were 12%. Colonization was associated with age less than 2 years (p < 0.001) and day care attenda nce for more than 20 hr/wk (p = 0.00005). More than half of these stra ins (62%) were resistant to penicillin, 33% having intermediate resist ance (minimal inhibitory concentration 0.06 to 1 mu g/ml) and 29%, hig h level resistance (minimal inhibitory concentration greater than or e qual to 2.0 mu g/ml). Penicillin resistance was associated with penici llin prophylaxis (p < 0.01). Many of these organisms were also resista nt to other classes of antibiotics. Conclusions: Although penicillin p rophylaxis and pneumococcal vaccine for patients with SCD have reduced overall nasopharyngeal colonization and disease caused by S. pneumoni ae (p < 0.001), a higher percentage of colonizing strains are now resi stant both to penicillin and to other antimicrobial agents (p < 0.01). Newer strategies for preventing disease and early management of suspe cted pneumococcal infection in these children must be developed.