Increasing penicillin and trimethoprim–sulfamethoxazole resistance in nasopharyngeal Streptococcus pneumoniae isolates from Guatemalan children, 2001–2006

SummaryObjectivesWe aimed to determine nasopharyngeal colonization rates and antibiotic resistance patterns of Streptococcus pneumoniae isolated from Guatemalan children, and to determine risk factors for colonization and antibiotic nonsusceptibility.MethodsIsolates were obtained from children aged 5 to 60 months attending public and private outpatient clinics and daycare centers during August 2001–June 2002 and outpatient clinics during November 2005–February 2006 in Guatemala City. Minimal inhibitory concentrations of penicillin, trimethoprim–sulfamethoxazole (TMS), cefotaxime, and erythromycin were determined using the E-test.ResultsThe overall nasopharyngeal colonization rate for S. pneumoniae was 59.1%. From 2001/2 to 2005/6 TMS nonsusceptibility increased from 42.4% to 60.8% (p < 0.05) in public clinics and from 51.4% to 84.0% (p = 0.009) in private clinics, and penicillin nonsusceptibility increased from 1.5% to 33.3% in public clinics (p < 0.001). Reported antibiotic use was not strictly associated with nonsusceptibility to that same antibiotic. Resistance to three or four antibiotics increased in public clinics from 2001/2 (0%) to 2005/6 (10.7%; p < 0.001). Risk factors for nasopharyngeal colonization with penicillin- or TMS-nonsusceptible S. pneumoniae were low family income, daycare center attendance, and recent penicillin use.ConclusionsIncreasing antibiotic nonsusceptibility rates in nasopharyngeal S. pneumoniae isolates from Guatemalan children reflect worldwide trends. Policies encouraging more judicious use of TMS should be considered.