title: Temporal evolution of carbapenem-resistant Acinetobacter baumannii in Curitiba, southern Brazil.
abstract: BACKGROUND
  In the last few years, carbapenem-resistant Acinetobacter baumannii isolates (CR-AB) have been identified worldwide. The first description of OXA-23-producing A baumannii in Brazil was from the city of Curitiba in 2003. The aim of the present study was to evaluate the persistence and dissemination of the first OXA-23-producing A baumannii clone isolated from patients in Hospital de Clinicas, Curitiba, Brazil.
  
  
  METHODS
  An antimicrobial susceptibility profile of the isolates was determined by the standard agar dilution method. Molecular detection of beta-lactamase genes was done by polymerase chain reaction. The clonal relationship of the isolates was analyzed by pulsed-field gel electrophoresis (PFGE). Epidemiologic and clinical features were evaluated as well.
  
  
  RESULTS
  Genotypic analysis of 172 CR-AB isolates by PFGE identified 3 distinct major PFGE clusters (A, B, and C, accounting for 36, 69, and 65 isolates, respectively). All isolates carried the bla(OXA-23)-like gene and were multidrug-resistant, but were susceptible to tigecycline and polymixin B. The mortality rate related to CR-AB infection was 45.4%, and ventilator-associated pneumonia and bloodstream infections were the most frequent clinical manifestations.
  
  
  CONCLUSIONS
  The presence of 3 clones among the CR-AB isolates suggests that cross-transmission was the main mechanism responsible for dissemination of OXA-23 producers. PFGE pattern A was genotypically similar to that of the first OXA-23-producing A baumannii clone identified in Curitiba in 1999. This clone persisted in the same hospital until April 2004. The presence of the bla(OXA-)23-like gene was the main mechanism associated with carbapenem resistance among the isolates studied.
authors.affiliation: Clinical Hospital, Federal University of Paraná, Curitiba, Brazil.
authors.forename: Karina Eugênia
authors.initials: KE
authors.lastname: Schimith Bier
authors.forename: Simone Oliveira
authors.initials: SO
authors.lastname: Luiz
authors.forename: Mara Cristina
authors.initials: MC
authors.lastname: Scheffer
authors.forename: Ana Cristina
authors.initials: AC
authors.lastname: Gales
authors.forename: Maria Cristina
authors.initials: MC
authors.lastname: Paganini
authors.forename: Agnaldo José do
authors.initials: AJ
authors.lastname: Nascimento
authors.forename: Evelyn
authors.initials: E
authors.lastname: Carignano
authors.forename: Libera Maria
authors.initials: LM
authors.lastname: Dalla Costa
mesh_terms: D000151:Acinetobacter Infections / Q000453:epidemiology* / Q000382:microbiology; D040981:Acinetobacter baumannii / Q000145:classification / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001426:Bacterial Proteins / Q000235:genetics; D015373:Bacterial Typing Techniques; D001938:Brazil / Q000453:epidemiology; D015780:Carbapenems / Q000494:pharmacology*; D002648:Child; D002675:Child, Preschool; D016172:DNA Fingerprinting; D004269:DNA, Bacterial / Q000235:genetics; D005260:Female; D022761:Gene Transfer, Horizontal; D006801:Humans; D007223:Infant; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D017720:Molecular Epidemiology; D016133:Polymerase Chain Reaction; D055815:Young Adult; D018440:beta-Lactam Resistance; D001618:beta-Lactamases / Q000235:genetics
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D015780:Carbapenems; D004269:DNA, Bacterial; D001618:beta-Lactamases