title: Detection of metallo-beta-lactamase producing Pseudomonas aeruginosa in intensive care units.
abstract: BACKGROUND
  Metallo-beta-lactamase (MBL) producing Pseudomonas aeruginosa has emerged as a threat to hospital infection control, due to its multi-drug resistance, especially in intensive care units (ICUs).
  
  
  OBJECTIVE
  This study was carried out to detect MBL producing P. aeruginosa isolates from medical and surgical ICUs, to compare and evaluate different phenotypic methods currently in use and to determine antibiograms.
  
  
  METHODS
  A prospective study was undertaken to detect MBLs in P. aeruginosa isolates obtained from various clinical samples. A total of 49 strains were recovered from patients admitted in inpatient wards and ICUs, and screened for imipenem resistance by Kirby Bauer disk diffusion method. Detection of MBLs was further done by imipenem-EDTA disk synergy test and combined disk test.
  
  
  RESULTS
  Out of 49 isolates, 11 isolates (22.4 per cent) were imipenem resistant. All 11 imipenem resistant P. aeruginosa strains, when further tested, were positive for MBL production by combined disk test, but, only eight showed positive results by imipenem-EDTA disk synergy test.
  
  
  CONCLUSIONS
  MBL production was the main resistance mechanism in the 11 carbapenem resistant P. aeruginosa isolates collected, with multidrug resistance associating significantly with MBL production in P. aeruginosa from our institution.
authors.affiliation: Department of Microbiology, Mahatma Gandhi Medical College and Research Institute, Pondicherry, India.
authors.forename: Arunava
authors.initials: A
authors.lastname: Kali
authors.affiliation: Department of Microbiology, Mahatma Gandhi Medical College and Research Institute, Pondicherry, India.
authors.forename: Sreenivasan
authors.initials: S
authors.lastname: Srirangaraj
authors.affiliation: Department of Microbiology, Mahatma Gandhi Medical College and Research Institute, Pondicherry, India.
authors.forename: Shailesh
authors.initials: S
authors.lastname: Kumar
authors.affiliation: Department of Microbiology, Mahatma Gandhi Medical College and Research Institute, Pondicherry, India.
authors.forename: Hema A
authors.initials: HA
authors.lastname: Divya
authors.affiliation: Department of Microbiology, Mahatma Gandhi Medical College and Research Institute, Pondicherry, India.
authors.forename: Akhila
authors.initials: A
authors.lastname: Kalyani
authors.affiliation: Department of Microbiology, Mahatma Gandhi Medical College and Research Institute, Pondicherry, India.
authors.forename: Sivaraman
authors.initials: S
authors.lastname: Umadevi
keywords: Metallo-beta-lactamases; Multidrug resistance; Pseudomonas aeruginosa; infection control