Curr Health Sci J, vol. 40, no. 2, 2014

Pseudomonas Aeruginosa Resistance Phenotypes and Phenotypic Highlighting Methods

[Review]

MARIA BALASOIU(1), A.T. BALASOIU(2), RODICA MANESCU(2), CARMEN AVRAMESCU(1), OANA IONETE(1)


(1)Department of Bacteriology, Virusology, Parasitology, UMF of Craiova,
(2)Clinic of Ophthalmology, Emergency County Hospital of Craiova


Abstract:

Pseudomonas aeruginosa genus bacteria are well known for their increased drug resistance (phenotypic ang genotypic resistance). The most important resistance mechanisms are: enzyme production, reduction of pore expression, reduction of the external membrane proteins expression, efflux systems, topoisomerase mutations. These mechanisms often accumulate and lead to multidrug ressitance strains emergence. The most frequent acquired resistance mechanisms are betalactamase-type enzyme production (ESBLs, AmpC, carbapenemases), which determine variable phenotypes of betalactamines resistance, phenotypes which are associated with aminoglycosides and quinolones resistance. The nonenzymatic drug resistance mechanisms are caused by efflux systems, pore reduction and penicillin-binding proteins (PBP) modification, which are often associated to other resistance mechanisms. Phenotypic methods used for testing these mechanisms are based on highlighting these phenotypes using Kirby Bauer antibiogram, clinical breakpoints, and “cut off” values recommended by EUCAST 2013 standard, version 3.1.


Keywords:
ESBLs, AmpC, Carbapenemase, genotypic resistance, phenotypic resistance



Corresponding:
Maria Balasoiu, M.D., PhD, University of Medicine and Pharmacy of Craiova, 2-4 Petru Rares St., Craiova, Romania


DOI 10.12865/CHSJ.40.02.01 - Download PDF