Carbapenem-resistant Pseudomonas aeruginosa strains from a Spanish hospital: Characterization of metallo-beta-lactamases, porin OprD and integrons

  1. Rojo-Bezares, B. 2
  2. Estepa, V. 1
  3. Cebollada, R. 4
  4. de Toro, M. 12
  5. Somalo, S. 1
  6. Seral, C. 34
  7. Castillo, F.J. 34
  8. Torres, C. 12
  9. Sáenz, Y. 2
  1. 1 Universidad de La Rioja
    info

    Universidad de La Rioja

    Logroño, España

    ROR https://ror.org/0553yr311

  2. 2 Centro de Investigación Biomédica de La Rioja
    info

    Centro de Investigación Biomédica de La Rioja

    Logroño, España

    ROR https://ror.org/03vfjzd38

  3. 3 Universidad de Zaragoza
    info

    Universidad de Zaragoza

    Zaragoza, España

    ROR https://ror.org/012a91z28

  4. 4 Hospital Clínico Universitario Lozano Blesa
    info

    Hospital Clínico Universitario Lozano Blesa

    Zaragoza, España

    ROR https://ror.org/03fyv3102

Revista:
International Journal of Medical Microbiology

ISSN: 1438-4221

Año de publicación: 2014

Volumen: 304

Número: 3-4

Páginas: 405-414

Tipo: Artículo

DOI: 10.1016/J.IJMM.2014.01.001 SCOPUS: 2-s2.0-84899658748 WoS: WOS:000336339500023 GOOGLE SCHOLAR

Otras publicaciones en: International Journal of Medical Microbiology

Resumen

Molecular typing and mechanisms of carbapenem resistance such as alterations in porin OprD and presence of metallo-beta-lactamases (MBLs), as well as integrons have been studied in a collection of carbapenem-resistant Pseudomonas aeruginosa (CRPA) isolates from a Spanish hospital. One hundred and twenty-three CRPA isolates were recovered from different samples of 80 patients. Clonal relationship among CRPA was analyzed by SpeI-PFGE. Susceptibility testing to 11 antibiotics and MBL phenotype was determined by microdilution, IP/IPI E-test and double disc method. The oprD gene was studied by PCR and sequencing, and mutations were determined comparing with P. aeruginosa PAO1 sequence. Characterization of MBLs, and class 1 and 2 integrons were studied by PCR and sequencing. SDS-PAGE analysis of outer membrane proteins of selected strains was performed. Seventy-four-per-cent of patients with CRPA were hospitalised in the ICU setting and 50% had long hospitalization stays. Sixty-four different PFGE patterns were detected, and 87 CRPA strains were further analyzed. MBL phenotype was detected in 43 of 87 strains (49.4%), which contained blaVIM-2 gene inside class 1 integrons. VIM-2-producing strains belonged to lineages ST175, ST235, and ST973. A great diversity of nucleotide insertions, deletions, and mutations in oprD gene, and the presence of a new insertion sequence (ISPa45) truncating oprD were identified among CRPA strains. Class 1 integrons were detected in 75% of CRPA strains, blaVIM-2 and the new arrangement aac(3)-Ia+ISPa34+aadA1 (named as In661) being the most frequent gene-cassette arrays detected. Other gene cassettes detected in integrons were: aadB, aadA6, aadA7, aac(6′)-Ib′, and blaOXA-46. © 2014 Elsevier GmbH. All rights reserved.