Assessment of antibiotic resistance in Klebsiella pneumoniae exposed to sequential in vitro antibiotic treatments

Abstract

BackgroundBacteria treated with different classes of antibiotics exhibit changes in susceptibility to successive antibiotic treatments. This study was designed to evaluate the influence of sequential antibiotic treatments on the development of antibiotic resistance in Klebsiella pneumoniae associated with β-lactamase and efflux pump activities.MethodsThe antibiotic susceptibility, β-lactamase activity, and efflux activity were determined in K. pneumoniae grown at 37 °C by adding initial (0 h) and second antibiotics (8 or 12 h). Treatments include control (CON; no first and second antibiotic addition), no initial antibiotic addition followed by 1 MIC ciprofloxacin addition (CON-CIP), no initial antibiotic addition followed by 1 MIC meropenem addition (CON-MER), initial 1/4 MIC ciprofloxacin addition followed by no antibiotic addition (1/4CIP-CON), initial 1/4 MIC ciprofloxacin addition followed by 1 MIC ciprofloxacin addition (1/4CIP-CIP), and initial 1/4 MIC ciprofloxacin addition followed by 1 MIC meropenem addition (1/4CIP-MER).ResultsCompared to the CON, the initial addition of 1/4 MIC ciprofloxacin inhibited the growth of K. pneumoniae throughout the incubation period. The ciprofloxacin treatments (CON-CIP and 1/4CIP-CIP) showed significant reduction in the number of K. pneumoniae cells compared to meropenem (CON-MER and 1/4CIP-MER). The 1/4CIP-CIP achieved a further 1 log reduction of K. pneumoniae, when compared to the 1/4CIP-CON and 1/CIP-MER. The increase in sensitivity of K. pneumoniae to cefotaxime, kanamycin, levofloxacin, nalidixic acid was observed for CON-CIP. Noticeable cross-resistance pattern was observed at the 1/4CIP-CIP, showing the increased resistance of K. pneumoniae to chloramphenicol, ciprofloxacin, kanamycin, levofloxacin, nalidixic acid norfloxacin, sulphamethoxazole/trimethoprim, and tetracycline. The levels of β-lactamase activities were estimated to be 8.4 μmol/min/ml for CON, 7.7 μmol/min/ml for 1/4CIP-CON and as low as 2.9 μmol/min/ml for CON-CIP. Compared to the absence of phenylalanine-arginine-β-naphthylamide (PAβN), the fluorescence intensity of EtBr was increased in K. pneumoniae cells treated at the CON, CON-CIP, and CON-MER in the presence of PAβN. However, the efflux pump activity remained in K. pneumoniae cells treated at the 1/CIP, 1/CIP–CIP, and 1/CIP-MER in the presence of PAβN.ConclusionThe results suggest that the pre-exposed antibiotic history, treatment order, and concentrations influenced the development of multiple antibiotic resistant associated with β-lactamase and efflux pump activities. This study highlights the importance of antibiotic treatment conditions, which would be taken into consideration when new antibiotic strategy is designed to prevent antibiotic resistance.

Systematic Investigation of Resistance Evolution to Common Antibiotics Reveals Conserved Collateral Responses across Common Human Pathogens

“…To date, there are several resistance evolution studies of individual members of the ESKAPE group (9,13,16,(56)(57)(58)(59)(60)(61); however, no study has examined the commonalities that arise from resistance evolution of these species under uniform conditions toward more than one class of antibiotic. A study by Michiels et al considered the persistence of the ESKAPE pathogens toward aminoglycosides but was performed under inconsistent environmental conditions (62).…”

Association between antimicrobial drug class for treatment and retreatment of bovine respiratory disease (BRD) and frequency of resistant BRD pathogen isolation from veterinary diagnostic laboratory samples

“…Recently, the effect of sequential antimicrobial treatments on the development of antimicrobial resistance has been demonstrated for Pseudomonas aeruginosa and Klebsiella pneumonia in vitro [28,29]. In these laboratory studies the emergence of antimicrobial resistance also varied with the classes and concentrations of antimicrobials used for pre-exposure and sequential treatments.…”

Analysis of the Correlation Between Antibiotic Resistance Patterns and Virulence Determinants in Pathogenic Klebsiella pneumoniae Isolates from Egypt

“…4 The proposed resistance mechanisms of K. pneumoniae to different classes of antimicrobial agents involve secretion of antimicrobial-degrading enzymes, alteration of antimicrobial target sites; change in membrane permeability, activation of efflux pump systems, and alteration of metabolic pathways. 5 Among these mechanisms, the enzymatic degradation and efflux pump systems seem to play a pivotal role, at least partly, in the development of multidrug resistance in K. pneumoniae. 6 K. pneumoniae strains produce destructive enzymes, for example, extendedspectrum b-lactamases (ESBLs), metallo-b-lactamases (MBLs), oxacillinases, and carbapenemases that have the ability to hydrolyze b-lactam antibiotics.…”