Detection of carbapenemase-producing Pseudomonas aeruginosa: Evaluation of the carbapenem inactivation method (CIM)

Autores organización

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  Elsa Piedad De La Cadena Vivas

  Autor

• 

  Christian Jose Pallares Gutierrez

  Autor

• 

  Maria Virginia Villegas Botero

  Autor

Autores

• Gutiérrez, S
• Correa, A
• Hernández-Gómez, C

Grupos de investigación

• Grupo de Investigación en Resistencia Antimicrobiana y Epidemiología Hospitalaria RAEH

  

  Investigador

  Maria Virginia Villegas Botero

Resumen

Introduction: The carbapenem inactivation method (CIM) is a cost-effective assay for detecting carbapenemases. However, its interpretation is unclear for Pseudomonas spp. We evaluate its accuracy when meropenem is changed to imipenem. Methods: We analyzed 266 P. aeruginosa isolates. The CIM method consists of: resuspend bacterial colonies (a full 10 mu l, loop) in 400 mu l water, in which a 10 mu g disk of meropenem/imipenem is immersed. After 2 h of incubation (35 degrees C), remove the disk, place it onto a Mueller-Hinton agar plate previously inoculated with Escherichia coli (ATCC 25922), and incubate at 35 degrees C between 18-24 h. Interpretation criteria (mm of inhibition zone): <= 19 mm, positive; >= 25 mm negative; 20-24 mm, undetermined. Results: Imipenem improves the sensitivity and specificity of CIM when compared to meropenem (99.4% and 98.9%, vs. 91.9% and 94.7%, respectively). Conclusions: The accuracy of CIM for carbapenemase detection in P. aeruginosa is increased with the use of imipenem. (C) 2019 Elsevier Espafia, S.L.U. and Sociedad Espanola de Enfermedades Infecciosas y Microbiologia Clinica. All rights reserved.

Copyright © 2019 Elsevier España, S.L.U. and Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.

Keywords

• Carbapenemases; Screening test; Carbapenemases phenotypic detection; Carbapenem inactivation method; Pseudomonas aeruginosa