Surveillance of antimicrobial resistance in isolates of Streptococcus pneumoniae and Haemophilus influenzae from children with community-acquired respiratory tract infection

Objective This surveillance was conducted in Beijing Children′s Hospital from 2000 to 2004 to determine the in vitro activity of selected antimicrobial agents against common respiratory pathogens,including Streptococcus pneumoniae and Haemophilus influenzae,isolated from children less than 5 years of age with respiratory tract infection.Methods Susceptibility testing was performed for 541 strains of S.pneumoniae and 521 strains of H.influenzae using the NCCLS(M100-S12) E test and K-B disk method.Results The prevalence of penicillin-non-susceptible pneumococci increased from 22% in 2000 to 32.9% in 2004(P(0.05)).The resistance rate of S.pneumoniae to cefaclor and cefuroxime increased from 7% to 25%(P(0.01)).The resistance rate of S.pneumoniae to erythromycin increased from 88% to 94.3%(P0.05).The proportion of ampicillin-resistant and β-lactamase-producing H.influenzae rose gradually from(5.0)% in 2000 to(14.3)% in 2004(P(0.05)).All H.influenzae strains were extremely susceptible to amoxicillin-clavulanic acid,cefuroxime,ceftriaxone.The proportion of cefaclor non-susceptible H.influenzae strains increased from 2% to(14.3)%(P0.01).Conclusions Penicillin non-susceptible S.pneumoniae isolates and ampicillin-resistant and beta-lactamase-producing H.influenzae strains increased significantly.