title: Macrolide resistance in Streptococcus pneumoniae isolated from Argentinian pediatric patients suffering from acute otitis media.
abstract: Macrolide-resistant Streptococcus pneumoniae emerged in Argentina in 1995, representing 26% of invasive infection isolates in children under 5 years old. The objectives of this study were to describe the prevalence of ermB and mefA genes in macrolide-resistant S. pneumoniae isolates from acute otitis media (AOM) and to determine their genetic relatedness. Between May 2009 and August 2010, 126 S. pneumoniae isolates from 324 otherwise healthy children with a first episode of AOM were included. Twenty six of these isolates (20.6%) were resistant to erythromycin. Most frequent serotypes were: 14 (46.2%), 6A (23.1%), 19F (7.7%) and 9V (7.7%). Twenty (76.9%) carried the mefA gene, 5 (19.2%) have the ermB gene, and 1 (3.9%) both ermB + mefA. Ten clonal types were identified, mostly related to Sweden(15A)-25/ST782 (SLV63), CloneB(6A)/ST473 and England(14)-9/ ST9. This is the first study assessing the mechanisms of macrolide resistance in pneumococci isolates from pediatric AOM in Argentina and their genetic relatedness.
authors.affiliation: Servicio de Microbiología, Hospital de Pediatría "Prof. Dr. J. P. Garrahan", Buenos Aires, Argentina.
authors.forename: Vanesa
authors.initials: V
authors.lastname: Reijtman
authors.affiliation: Servicio Antimicrobianos, Instituto Nacional de Enfermedades Infecciosas, ANLIS "Dr. Carlos G. Malbrán", Buenos Aires, Argentina.
authors.forename: Paula
authors.initials: P
authors.lastname: Gagetti
authors.affiliation: Servicio Antimicrobianos, Instituto Nacional de Enfermedades Infecciosas, ANLIS "Dr. Carlos G. Malbrán", Buenos Aires, Argentina.
authors.forename: Diego
authors.initials: D
authors.lastname: Faccone
authors.affiliation: Servicio Antimicrobianos, Instituto Nacional de Enfermedades Infecciosas, ANLIS "Dr. Carlos G. Malbrán", Buenos Aires, Argentina.
authors.forename: Sofía
authors.initials: S
authors.lastname: Fossati
authors.affiliation: Servicio de Otorrinolaringología, Hospital de Pediatría "Prof. Dr. J. P. Garrahan", Buenos Aires, Argentina.
authors.forename: Patricia
authors.initials: P
authors.lastname: Sommerfleck
authors.affiliation: Servicio de Microbiología, Hospital de Pediatría "Prof. Dr. J. P. Garrahan", Buenos Aires, Argentina.
authors.forename: Claudia
authors.initials: C
authors.lastname: Hernández
authors.affiliation: Servicio de Otorrinolaringología, Hospital de Pediatría "Prof. Dr. J. P. Garrahan", Buenos Aires, Argentina.
authors.forename: Patricia
authors.initials: P
authors.lastname: Bernáldez
authors.affiliation: Servicio de Microbiología, Hospital de Pediatría "Prof. Dr. J. P. Garrahan", Buenos Aires, Argentina. Electronic address: hlopar25@gmail.com.
authors.forename: Horacio
authors.initials: H
authors.lastname: Lopardo
authors.affiliation: Servicio Antimicrobianos, Instituto Nacional de Enfermedades Infecciosas, ANLIS "Dr. Carlos G. Malbrán", Buenos Aires, Argentina.
authors.forename: Alejandra
authors.initials: A
authors.lastname: Corso
mesh_terms: D000900:Anti-Bacterial Agents; D001118:Argentina; D002648:Child; D002675:Child, Preschool; D024881:Drug Resistance, Bacterial; D006801:Humans; D007223:Infant; D018942:Macrolides / Q000494:pharmacology*; D008826:Microbial Sensitivity Tests; D010033:Otitis Media / Q000382:microbiology*; D013296:Streptococcus pneumoniae / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification
chemical_list: D000900:Anti-Bacterial Agents; D018942:Macrolides
keywords: Acute otitis media; Macrolide resistance; Otitis media aguda; Resistencia a macrólidos; Streptococcus pneumoniae