Microbiology: Current Research

Editorial - Microbiology: Current Research (2018) Volume 2, Issue 1

Focus on the problem of carbapenem resistance in clinical significant non-fermenters: Acinetobacter baumannii and Pseudomonas aeruginosa

Few decades after the implementation of the potential broad spectrum antimicrobials, the antibiotic resistance turns into a global problem. The non-fermenters of clinical significance Acinetobacter baumannii and Pseudomonas aeruginosa, usually considered as opportunistic pathogens, nowadays emerge to evolve in ones of the most problematic causative agents of infections. The therapeutic restrictions are determined on one hand due to their intrinsic resistance to a great variety of antibiotics and on the other to the arising acquired resistance. The carbapenem resistance is a growing tendency worldwide and usually it is not an isolated phenomenon, but combined with resistance against other antibiotic groups. Carbapenems not long ago assumed to be, ”the heavy artillery” of the antibiotic therapy today face the disability to be effective in the treatment of infections caused by multi-drug-resistant bacteria (MDR). The production of bla OXA-23, OXA-24, OXA-58 and the hyperexpression of OXA-51 due to ISAba1 insertion sequence are the leading cause of carbapenem resistance in Acinetobacter baumannii [1]. This tendency is observed in Bulgaria as well [2-5]. The loss of OprD transmembrane protein sometimes combined with overexpression of the intrinsic AmpC and the overexpression of some efflux pumps are considered as main factors for carbapenem resistance in Pseudomonas aeruginosa whereas metallo-enzymes’ production has a secondary role [6,7]. Two major studies proved that in Bulgarian clinical isolates Pseudomonas aeruginosa the increased expression or overexpression of MexXY-OprM efflux pump sometimes combined with overexpression of MexAB-OprM with or without loss of the OprD is the main mechanism of determining this type of resistance. Metallo-enzyme production and overexpression of the intrinsic AmpC are rarely involved [8,9].

Author(s): Petrova A, Murdjeva M

Abstract Full Text PDF