Your browser doesn't support javascript.
loading
Diversity of mechanisms conferring resistance to ß-lactams among OXA-23-producing Acinetobacter baumannii clones.
Cardoso, Juliana Provasi; Cayô, Rodrigo; Girardello, Raquel; Gales, Ana Cristina.
Afiliação
  • Cardoso JP; Laboratório Alerta, Disciplina de Infectologia, Departamento de Medicina, Universidade Federal de São Paulo-UNIFESP, São Paulo, SP, Brazil.
  • Cayô R; Laboratório Alerta, Disciplina de Infectologia, Departamento de Medicina, Universidade Federal de São Paulo-UNIFESP, São Paulo, SP, Brazil. Electronic address: rodrigocayosilva@gmail.com.
  • Girardello R; Laboratório Alerta, Disciplina de Infectologia, Departamento de Medicina, Universidade Federal de São Paulo-UNIFESP, São Paulo, SP, Brazil.
  • Gales AC; Laboratório Alerta, Disciplina de Infectologia, Departamento de Medicina, Universidade Federal de São Paulo-UNIFESP, São Paulo, SP, Brazil.
Diagn Microbiol Infect Dis ; 85(1): 90-7, 2016 May.
Article em En | MEDLINE | ID: mdl-26971181
A total of 31 unrelated OXA-23-producing Acinetobacter baumannii strains isolated from 14 hospitals located in distinct Brazilian regions were evaluated in this study. These isolates were grouped into 12 different sequence types (STs), of which 7 had unique allelic sequences (ST188, ST189, ST190, ST191, ST192, ST228, and ST299). Most isolates belonged to the clonal complex CC79 followed by CC15 and CC1. Only polymyxin B and minocycline showed good activity against the OXA-23-producing A. baumannii clones. The ISAba1 upstream blaOXA-23, blaOXA-51-like, or ampC was found in 100%, 54.8%, and 77.4% of the isolates, respectively. High resistance rates to ceftazidime and cefotaxime were observed among those isolates possessing ISAba1 upstream ampC, in contrast to those isolates that did not carry this configuration. Moreover, a ≥2 Log2 decrease in the MICs of meropenem and ceftazidime was observed in the presence of phenyl-arginine-ß-naphthylamide for 80.6% and 54.8% of isolates, respectively. Overexpression of the adeB was observed in 61.3% of isolates, particularly among those isolates belonging to the ST1 (CC1). It was also verified that ompW was down-regulated in all isolates belonging to the ST15 (CC15). On the other hand, carO and omp33-36 genes were overexpressed in 48.4% and 58.1% of the isolates, respectively. In this study, we show that overexpression of AdeABC system could significantly contribute for resistance to meropenem and ceftazidime among OXA-23-producing A. baumannii clones in Brazil, demonstrating the complexity involved in the ß-lactam resistance in such isolates.
Assuntos
Palavras-chave
Texto completo
Adicionar na Minha BVS
Imprimir
XML
PubMed Links
Buscar no Google

Texto completo: 1 Coleções: 01-internacional Base de dados: MEDLINE Assunto principal: Beta-Lactamases / Resistência beta-Lactâmica / Acinetobacter baumannii Limite: Humans País/Região como assunto: America do sul / Brasil Idioma: En Revista: Diagn Microbiol Infect Dis Ano de publicação: 2016 Tipo de documento: Article País de afiliação: Brasil País de publicação: Estados Unidos
Texto completo
Adicionar na Minha BVS
Imprimir
XML
PubMed Links
Buscar no Google

Texto completo: 1 Coleções: 01-internacional Base de dados: MEDLINE Assunto principal: Beta-Lactamases / Resistência beta-Lactâmica / Acinetobacter baumannii Limite: Humans País/Região como assunto: America do sul / Brasil Idioma: En Revista: Diagn Microbiol Infect Dis Ano de publicação: 2016 Tipo de documento: Article País de afiliação: Brasil País de publicação: Estados Unidos