Phenotypic Characterization of Non-Beta Lactam Multidrug Resistance in Extended-Spectrum Beta-Lactamase Producer and Non-Producer Enterobacteriaceae

Abstract

Purpose: The aim of this study is to detect the correlations between ESBL-producing, and the pattern, and extensiveness of MDR of other common non-betalactam antibiotics in Enterobacteriaceae strains. Methods: A total of 170 ESBL-producer strains and the same amount of ESBL-non-producer Enterobacteriaceae strains were collected as study and control groups from our Clinical Microbiology Laboratory. Antibiotic susceptibility tests and ESBL detection were conducted on both microorganism groups by routine bacteriologic methods. The antibiotic susceptibilities have been listed on a strain basis, and they were classified according to the extensiveness of resistances. Results: When comparing the ESBL-producer to the ESBL-nonproducer strains, higher individual resistance rates were detected to fluoroquinolones, trimethoprim/ sulfamethoxazole, aminoglycosides, piperacillin/ tazobactam, nitrofurantoin and carbapenems in various percentages (69. 40% vs 23. 50%; 68.20% vs 30%; 34. 70% vs 5. 30%; 27. 20% vs 4.73%; 23.50% vs 1.90 and 18.90% vs 5.20% respectively). The three to six-drug MDRs in the same isolate has been found in 36 different strains of ESBL-p, although no strains were detected in the control group (21% vs 0). The three most prevalent triplet co-existences of MDR were sulfamethoxazole/trimethoprim+fluoroquinolones +aminoglycosides, and sulfamethoxazole/trimethoprim +fluoroquinolones+piperacillin/tazobactam, and sulfamethoxazole/trimethoprim+fluoroquinolones +carbapenem resistance combinations in both groups, but, their proportions were statistically higher in the study group (43 vs 4, 31 vs 3, and 22 vs 1 strains). Conclusions: ESBL and carbapenemase-producing Enterobacteriaceae control the other wide range of non-beta-lactam antibiotic resistance in various combinations, according to our study.