Multiplex PCR to determine Streptococcus pneumoniae serotypes causing otitis media in the Republic of Ireland with further characterisation of antimicrobial susceptibilities and genotypes
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The purpose of this study was to determine the serotypes, genotypes and antimicrobial susceptibilities of Streptococcus pneumoniae causing otitis media (OM) in children in Dublin, Ireland. S. pneumoniae isolates (n = 28) from spontaneously discharging OM were studied. Serotyping was performed using a previously undescribed multiplex polymerase chain reaction (PCR) scheme in combination with serological methods. Multilocus sequence typing (MLST) was performed using standard procedures. Antimicrobial susceptibility testing was performed using the Etest method. Fourteen different S. pneumoniae serotypes were identified. The five most common serotypes were 3, 19F, 19A, 14 and 6A, which accounted for 68% of all infections. The 7-valent pneumococcal conjugate vaccine (PCV7), 10-valent pneumococcal conjugate vaccine (PHiD-CV) and 13-valent pneumococcal conjugate vaccine (PCV13) provided potential coverages of 43%, 46% and 86%, respectively. Reduced susceptibility to penicillin was evident for 25% of isolates and was associated with serotypes 14, 19A, 19F and 9V. A total of 21 different sequence types (STs) were identified. Pneumococcal Molecular Epidemiology Network (PMEN) clones or their variants represented 54% (15/28) of all isolates. Continued monitoring and characterisation of S. pneumoniae causing OM in Ireland is warranted in order to guide future vaccine and treatment policies.
KeywordsOtitis Medium Multiplex Polymerase Chain Reaction Tigecycline Pneumococcal Conjugate Vaccine Penicillin Resistance
We are grateful to the staff of the Children’s University Hospital, Temple St., Dublin, for their assistance with the collection of the isolates used in this study. We also wish to thank the Health Protection Surveillance Centre, which financially supports the laboratory surveillance of pneumococcal disease in Ireland. We acknowledge the use of the pneumococcal MLST database, which is located at Imperial College London and funded by the Wellcome Trust.
- 8.Whatmore AM, Efstratiou A, Pickerill AP, Broughton K, Woodard G, Sturgeon D et al (2000) Genetic relationships between clinical isolates of Streptococcus pneumoniae, Streptococcus oralis, and Streptococcus mitis: characterization of “Atypical” pneumococci and organisms allied to S. mitis harboring S. pneumoniae virulence factor-encoding genes. Infect Immun 68:1374–1382CrossRefPubMedGoogle Scholar
- 14.Clinical and Laboratory Standards Institute (CLSI) (2008) Performance standards for antimicrobial susceptibility testing; eighteenth informational supplement. M100-S18. CLSI, Wayne, PAGoogle Scholar
- 28.Reinert RR, van der Linden M, Seegmüller I, Al-Lahham A, Siedler A, Weissmann B et al (2007) Molecular epidemiology of penicillin-non-susceptible Streptococcus pneumoniae isolates from children with invasive pneumococcal disease in Germany. Clin Microbiol Infect 13:363–368CrossRefPubMedGoogle Scholar
- 32.Carvalho Mda G, Pimenta FC, Gertz RE Jr, Joshi HH, Trujillo AA, Keys LE et al (2009) PCR-based quantitation and clonal diversity of the current prevalent invasive serogroup 6 pneumococcal serotype, 6C, in the United States in 1999 and 2006 to 2007. J Clin Microbiol 47:554–559CrossRefPubMedGoogle Scholar