title: Molecular epidemiology of Streptococcus agalactiae recovered from significant bacteriuria.
abstract: BACKGROUND
  Streptococcus agalactiae has been implicated in urinary tract infections, but the molecular epidemiology of such infections is poorly characterized.
  
  
  METHODS
  In this study, 194 isolates recovered from significant bacteriuria of non-pregnant individuals were submitted to antimicrobial susceptibility testing, molecular characterization of macrolide resistance, PCR-based capsular typing and analysis of genetic diversity by pulsed-field gel electrophoresis (PFGE).
  
  
  RESULTS
  By disk diffusion, all isolates were susceptible to ceftriaxone, levofloxacin, penicillin G and vancomycin; 87.6% and 9.3% of isolates were non-susceptible to tetracycline and clindamycin, respectively. The minimum inhibitory concentration (MIC) confirmed that 11.3% of isolates were resistant to erythromycin. Macrolide resistance determinants were iMLSB (n = 9), cMLSB (n = 9) and M (n = 4), associated with ermA, ermB and mefA/E. Predominant capsular types were V, Ia, II and III. No significant association was observed between any capsular type and the occurrence of pyuria. However, type III was associated with erythromycin resistance, while type II was associated with erythromycin-susceptible isolates. Distinct PFGE profiles were observed among different types, but identical profiles were found among erythromycin-susceptible and -resistant isolates of the same type.
  
  
  CONCLUSIONS
  A variety of capsular and PFGE types are involved in significant bacteriuria. Although capsular types found here are prevalent in different infections, the frequency of each type seems to be unique. Erythromycin resistance is due to polyclonal origin instead of the expansion of few clones of S. agalactiae.
authors.affiliation: From the Departamento de Microbiologia e Parasitologia, Instituto Biomédico, Universidade Federal Fluminense , Rio de Janeiro , Brazil.
authors.forename: Rôde B B
authors.initials: RB
authors.lastname: Schuab
authors.forename: Glauber P
authors.initials: GP
authors.lastname: Arêas
authors.forename: Viviane C
authors.initials: VC
authors.lastname: Souza
authors.forename: Rosana R
authors.initials: RR
authors.lastname: Barros
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001437:Bacteriuria / Q000453:epidemiology / Q000382:microbiology*; D002648:Child; D016521:Electrophoresis, Gel, Pulsed-Field; D005260:Female; D006801:Humans; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D017720:Molecular Epidemiology; D013290:Streptococcal Infections / Q000453:epidemiology / Q000382:microbiology*; D013292:Streptococcus agalactiae / Q000187:drug effects / Q000235:genetics*; D014552:Urinary Tract Infections / Q000453:epidemiology / Q000382:microbiology*; D055815:Young Adult
chemical_list: D000900:Anti-Bacterial Agents
keywords: Antimicrobial resistance; Streptococcus agalactiae; capsular typing; pulsed-field gel electrophoresis; urinary tract infection