Detection of quinolone resistance from nosocomial pathogens

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Detection of quinolone resistance from nosocomial pathogens

INTRODUCTION

INTRODUCTION

Fluoroquinolones  have  been  frequently  prescribed  as  empirical  therapy  against  mosthospital  and  community  infections  due  to  increased  appearance  of  multiple  drug  resistantGram negative bacteria includingKlebsiella pneumoniaeand to the disease severity.Withextensive  clinical  use  of  quinolones.  Fluoroquinolone  resistance  has  been  a  problem  inclinical  medicine  for  its  limiting  of  available  agents  in  the  treatment  of  many  types  ofinfection.Quinolone   resistance   in   the   family   Enterobacteriaceae   is   mostly   attributed   to   theaccumulation  of  mutations  in  the  bacterial  enzymes  targeted  by:  DNA  gyrase  and  DNAtopoisomerase IV. In addition  Active efflux systems (acrAB-TolC) resulting in decreasedintracellular   accumulation   of   fluoroquinolones   inK.pneumoniae.Morever,Plasmid-mediated  quinolone  resistance  (PMQR)  with  the  potential  for  horizontal  transfer  has  beendescribed along with three mechanisms: (i) a quinolone-protective mechanism encoded by theqnrgenes(3); (ii) a modifying enzyme, aac(60)-Ib-crand (iii) an efflux pump encoded by theqepAgene(5,6).   Plasmid-encoded   quinolone   resistance   determinants   confer   low-levelresistance,  but  their  presence  could  potentially  facilitate  the  evolution  of  the  bacterial  hosttoward  higher  levels  of  resistance  by  mutational  alterations  in  type  II  topoisomerases.K.pneumoniaestrains represent an incredibly great epidemic potential and are one of the majorsources   of   horizontally   spreading   antimicrobial   resistance(2).Fluoroquinolone   resistantK.pneumoniaeconstitutes one of the most common Gram-negative bacteria showing multipleantibiotic  resistance  worldwide

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