title: β-Lactam resistance, serotype distribution, and genotypes of meningitis-causing Streptococcus pneumoniae, Rio de Janeiro, Brazil.
abstract: BACKGROUND
  Here, we report a laboratory-based study of Streptococcus pneumoniae recovered from patients with meningitis in Rio de Janeiro State, Brazil.
  
  
  METHODS
  The aim of this study was to determine the evolution of β-lactam resistance, antimicrobial susceptibility pattern, serotypes, and genetic diversity of S. pneumoniae, isolated from meningitis patients between 2000 and 2008.
  
  
  RESULTS
  A total of 264 S. pneumoniae recovered from patients between 2000 and 2008 were included. Susceptibility testing (E-test) of S. pneumoniae showed resistance to penicillin, ceftriaxone, oxacillin, cotrimoxazole, tetracycline, ofloxacin, erythromycin, chloramphenicol, and rifampicin. Penicillin resistance (PEN-R, minimal inhibitory concentration [MIC] ≥ 0.12 μg/mL) increased from 8% of isolates in 2000-2002, to 12% in 2003-2005, and to 20% in 2006-2008. Ceftriaxone resistance (MIC ≥ 1.0 μg/mL) was detected among some PEN-R isolates (13%) from 2004 onward. Within the PEN-R isolates, serotypes that are included in 10-valent pneumococcal conjugate vaccine predominated (90%), and resistance was detected mostly in isolates of serotypes 14 (61%), 23F (16%), 6B (10%), and 19F (3%). Multilocus sequence typing showed that 52% of the PEN-R isolates, and 89% of those with MICs ≥ 0.5 μg/mL, were sequence type (ST)-156 or single-locus variants of this ST (ST-557 or ST-4388); all of these isolates were serotype 14 and were assigned to the Spain-3 clone.
  
  
  CONCLUSIONS
  β-lactam resistance increased recently among cerebrospinal fluid isolates and was mainly due to the surge of the ST-4388, a previously undescribed gki single-locus variants of ST-156. Regional surveillance is shown to be essential to provide optimal antimicrobial therapy, monitor highly successful clones, and formulate adequate vaccination strategy.
authors.affiliation: Laboratory of Biochemical Systematics, Oswaldo Cruz Institute, FIOCRUZ, Rio de Janeiro, Brazil. barroso@ioc.fiocruz.br
authors.forename: David E
authors.initials: DE
authors.lastname: Barroso
authors.forename: Daniel
authors.initials: D
authors.lastname: Godoy
authors.forename: Terezinha M P P
authors.initials: TM
authors.lastname: Castiñeiras
authors.forename: Mary M
authors.initials: MM
authors.lastname: Tulenko
authors.forename: Maria C
authors.initials: MC
authors.lastname: Rebelo
authors.forename: Lee H
authors.initials: LH
authors.lastname: Harrison
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001938:Brazil / Q000453:epidemiology; D002555:Cerebrospinal Fluid / Q000382:microbiology; D002648:Child; D002675:Child, Preschool; D005260:Female; D014644:Genetic Variation; D005838:Genotype; D006801:Humans; D007223:Infant; D008297:Male; D008586:Meningitis, Pneumococcal / Q000453:epidemiology* / Q000382:microbiology; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D012703:Serotyping; D013296:Streptococcus pneumoniae / Q000145:classification* / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification; D055815:Young Adult; D018440:beta-Lactam Resistance
chemical_list: D000900:Anti-Bacterial Agents