title: Low-level resistance and clonal diversity of Pseudomonas aeruginosa among chronically colonized cystic fibrosis patients.
abstract: A prospective study was conducted in Brazil to evaluate antimicrobial resistance patterns and molecular epidemiology of Pseudomonas aeruginosa isolates from cystic fibrosis (CF) patients with chronic lung infection. All isolates were obtained between May 2009 and June 2010 from 75 patients seen in four reference centers in Brazil: HCPA (20 patients) and HEOM (15 patients), located in southern and northeastern Brazil, respectively; IFF (20 patients) and HUPE (20 patients), both in southwestern Brazil. Antimicrobial susceptibility testing, PCR for detection of carpapenemases, and pulsed-field gel electrophoresis (PFGE) were performed in 274 isolates. A total of 224 PFGE types were identified and no clones were found circulating among the centers or within the same center. Despite the chronic infection, most patients were colonized by intermittent clones. Only three patients (4%) maintained the same clone during the study. The resistance rates were lower than 30% for the majority of antimicrobials tested in all centers and only 17% of isolates were multiresistant. Isolates (n = 54) with reduced susceptibility to imipenem and/or meropenem presented negative results for blaSPM-1, blaIMP-1, blaVIM , and blaKPC genes. Our results indicate an unexpected low level of antimicrobial resistance and a high genotypic diversity among P. aeruginosa from Brazilian chronic CF patients.
authors.affiliation: Disciplina de Microbiologia e Imunologia, Faculdade de Ciências Médicas, Universidade do Estado do Rio de Janeiro, Boulevard 28 de Setembro, 87, fundos, Rio de Janeiro, RJ, Brazil.
authors.forename: Alex Guerra
authors.initials: AG
authors.lastname: Ferreira
authors.affiliation: Disciplina de Microbiologia e Imunologia, Faculdade de Ciências Médicas, Universidade do Estado do Rio de Janeiro, Boulevard 28 de Setembro, 87, fundos, Rio de Janeiro, RJ, Brazil.
authors.forename: Robson Souza
authors.initials: RS
authors.lastname: Leão
authors.affiliation: Laboratório de Pesquisa em Infecção Hospitalar, IOC/Instituto Oswaldo Cruz, Rio de Janeiro, RJ, Brazil.
authors.forename: Ana Paula D'alincourt
authors.initials: AP
authors.lastname: Carvalho-Assef
authors.affiliation: Hospital Universitário Pedro Ernesto, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, RJ, Brazil.
authors.forename: Érica Aparecida dos Santos Ribeiro
authors.initials: ÉA
authors.lastname: da Silva
authors.affiliation: Hospital Universitário Pedro Ernesto, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, RJ, Brazil.
authors.forename: Monica de Cássia
authors.initials: Mde C
authors.lastname: Firmida
authors.affiliation: Instituto Fernandes Figueira, Fundação Instituto Oswaldo Cruz, Rio de Janeiro, RJ, Brazil.
authors.forename: Tania Wrobel
authors.initials: TW
authors.lastname: Folescu
authors.affiliation: Serviço de Pneumologia, Hospital Especializado Octávio Mangabeira, Salvador, BA, Brazil.
authors.forename: Vilma Almeida
authors.initials: VA
authors.lastname: Paixão
authors.affiliation: Serviço de Pneumologia, Hospital Especializado Octávio Mangabeira, Salvador, BA, Brazil.
authors.forename: Maria Angélica
authors.initials: MA
authors.lastname: Santana
authors.affiliation: Faculdade de Medicina, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil.
authors.forename: Fernando Antonio
authors.initials: FA
authors.lastname: de Abreu e Silva
authors.affiliation: Laboratório de Pesquisa em Resistência Bacteriana - Centro de Pesquisas Experimental Hospital de Clínicas de Porto Alegre, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil.
authors.forename: Afonso Luís
authors.initials: AL
authors.lastname: Barth
authors.affiliation: Disciplina de Microbiologia e Imunologia, Faculdade de Ciências Médicas, Universidade do Estado do Rio de Janeiro, Boulevard 28 de Setembro, 87, fundos, Rio de Janeiro, RJ, Brazil.
authors.forename: Elizabeth Andrade
authors.initials: EA
authors.lastname: Marques
mesh_terms: D000293:Adolescent; D000328:Adult; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D001426:Bacterial Proteins / Q000235:genetics*; D001938:Brazil / Q000453:epidemiology; D015780:Carbapenems / Q000627:therapeutic use; D002648:Child; D003550:Cystic Fibrosis / Q000382:microbiology*; D024901:Drug Resistance, Multiple, Bacterial / Q000235:genetics*; D006801:Humans; D008826:Microbial Sensitivity Tests; D017720:Molecular Epidemiology; D011446:Prospective Studies; D011552:Pseudomonas Infections / Q000188:drug therapy* / Q000453:epidemiology; D011550:Pseudomonas aeruginosa / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification; D055815:Young Adult; D001618:beta-Lactamases / Q000235:genetics*
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D015780:Carbapenems; D001618:beta-Lactamases; C063912:carbapenemase
keywords: Cystic fibrosis; Pseudomonas aeruginosa; antimicrobial resistance; molecular epidemiology