Screening of extended-spectrum β-lactamase-producing klebsiella bacteria isolated from Clinical and Microbiological sample

Screening of extended-spectrum β-lactamase-producing klebsiella bacteria isolated from Clinical and Microbiological sample
zahra baseri,^1,* Mojtaba Mortazavi,² Amir Savardashtaki,³ Kambiz Iraji,⁴ Masoud Torkzadeh,⁵
2. Department of Biotechnology, Institute of Science and High Technology and Environmental Science, Graduate University of Advanced Technology, Kerman, Iran
3. Department of Medical Biotechnology, School of Advanced Medical Sciences and Technologies Shiraz University of Medical Sciences Shiraz Iran
4. Department of Medical Biotechnology, School of Advanced Medical Sciences and Technologies Shiraz University of Medical Sciences Shiraz Iran
5. Department of Biotechnology, Institute of Science and High Technology and Environmental Science, Graduate University of Advanced Technology, Kerman, Iran
Introduction: ESBLs stand for Extended-Spectrum β-lactamase which are enzymes produced by some bacteria and make them resistant to some antibiotics. They can hydrolyze third- and fourth-generation of cephalosporins and monobactams, but not cephamycins or carbapenems. the ESBLs produced by Klebsiella pneumoniae is an important clinical concern in the worldwide. Klebsiella spp, especially Klebsiella pneumoniae and Klebsiella oxytoca, are the most common pathogens causing pneumonia, meningitis, urinary tract infections and bloodstream infections. Klebsiellae have developed resistance to a wide range of antibiotics such as aminoglycosides, cephalosporins and wide range of β-lactams, including carbapenems, and have posed serious problems in antibiotic management with limited treatment options. The aim of this study was to identification and screening of the beta-lactamase producing Klebsiella.
Methods: In this study, a cross-sectional descriptive-analytical study was conducted over a period of 3 months. 36 specimens of Klebsiella were identified by biochemical-differential methods collected by culturing of urine, blood, secretions and sputum. Isolates were tested for antibiotic susceptibility. Phenotypic identification of 35 klebsiella isolats for ESBL production was confirmed by double disc synergy test, phenotypic confirmatory double disc test. The seven isolates with ESBL phenotype were sequenced by 16SrRNA molecular identification method.
Results: Among 36 Klebsiella isolates, 15 isolates (41.6%) produced ESBL. Antibiotic resistance in beta-lactamase-producing bacteria against ceftazidime, cefotaxime, and cefixime (92.8%) was higher than other antibiotics. Among the resistant isolates, the major identified species were Klebsiella Pneumoniae (71.42 %), Klebsiella oxytoca (14.27 %), Klebsiella quasipneumoniae (14.27 %).
Conclusion: Based on this study and sequencing of Klebsiella isolates, Klebsiella pnemoniea the most resistant isolated species against a wide range of antibiotics.
Keywords: Extended-spectrum b-lactamases (ESBL), Klebsiella bacterium, Antibiotic resistance