Antibiotic susceptibility of Streptococcus pneumoniae colonizing the nasopharynx of Colombian children with pneumonia1

Streptococcus pneumoniae is one of the principal causal agents of acute respiratory infection (ARI) in children, and its resistance to antibiotics has increased worldwide. This study examined the patterns of susceptibility to antibiotics of S. pneumoniae that had colonized the upper respiratory tract of 272 children hospitalized for pneumonia in two hospitals in Santafé de Bogotá. S. pneumoniae was isolated from 114 patients (42%). Diminished susceptibility to penicillin was noted in 19 isolates (17%), with 12 (11%) having an intermediate level of sensitivity and 7 (6%) showing outright resistance. Only 1 of the 19 isolates resistant to penicillin also showed resistance to ceftriaxone. There was diminished sensitivity to erythromycin in 3 isolates (3%), to chloramphenicol in 6 (5%), and to co-trimoxazole (trimethoprim + sulfamethoxazole) in 46 (40%). Resistance to multiple drugs was found in 7 isolates (6%). The most commonly encountered penicillinresistant serotype was 23F (68.4%). An association was observed between age, prior use of antibiotics, and colonization by S. pneumoniae with reduced penicillin sensitivity or multiple-drug resistance. This study confirmed the presence of antibiotic-resistant S. pneumoniae in Colombia and highlights the importance of the rational use of antibiotics and of the implementation of epidemiologic surveillance for this agent. ABSTRACT