Detection of Extended Spectrum Beta Lactamase Producing Escherichia Coli and Klebsiella Species Isolated from Urine Samples of UTI Patients by Phenotypic and Genotypic Methods

Abstract

Background: Escherichia coli and Klebsiella spp. are the most common organisms causing urinary tract infection (UTI) and commonly responsible for extended spectrum beta lactamase (ESBL) production. This study was carried out to detect ESBL producing uropathogenic Escherichia coli and Klebsiella spp. by phenotypic and genotypic method. Rapid and accurate detection of ESBL producing E. coli and Klebsiella spp. has an important role to avoid treatment failure. Materials and Methods: This was a cross sectional observational study and carried out in department of microbiology in Chittagong Medical College, Bangladesh from January to December 2017. Urine was collected from suspected UTI patients and standard microbiological and biochemical tests were carried out. ESBL producing E. coli and Klebsiella spp. were identified by phenotypic confirmatory disc diffusion test (PCDDT). Polymerase chain reaction (PCR) was performed by using standard protocol with specific primers. Results: 448 urine samples were collected. Among them, 140 showed bacterial growth; 72 were E. coli and 35 were Klebsiella spp. Among E. coli 38(52.8%) and in Klebsiella spp. 15(42.9%) were detected as ESBL producers by PCDDT respectively. Among E. coli, 41(56.9%) and in Klebsiella spp. 21(60%) strains produced ESBL genes by PCR. Out of 38 phenotypically positive E. coli, 7 strains do not carry any detectable genes. Similarly, out of 15 phenotypically positive Klebliella spp. 3 isolates did not produce any detectable gene. On the other hand, 10 E. coli isolates and 9 Klebsiella spp. carry detectable genes although these were not phenotypically ESBL producers. Moreover, ESBL producing E. coli and Klebsiella spp. showed more multidrug resistant than Non-ESBL producing E. coli and Klebsiella spp. Conclusion: This study revealed that large portion of E. coli and Klebsiella spp. was ESBL producers. PCR can detect some additional cases of ESBL producing isolates. So, PCR can be used along with phenotypic ......