Survey of TEM Type Extended-Spectrum β-Lactamases) ESBL (in Clinical Isolates of Escherichia Coli by Phenotypic and Genotypic Methods

Extended-spectrum β-lactamases (ESBLs) enzymes are one of the reasons for accruing drug resistance in E. coli isolates. The aim of this research was to investigate the antibacterial susceptibility patterns of isolates to β-lactam antibiotics and also to study the presence of blaTEM gene in E. coli isolates. During 5 months, 188 isolates of E. coli were collected from Imam Reza and Shahid Madani hospitals of Tabriz and clinical centers of Khoy and identified by differential tests. In order to determine resistant patterns of isolates to antibiotics, disk diffusion method was used. The production of ESBLs in isolates resistant to ceftazidime was determined by combined disk test (CDT). Polymerase chain reaction (PCR) was carried out for the detection of blaTEM. Of 94 isolates collected from Tabriz, 29 (30. 85%) and 38 isolates (40. 42%) were respectively resistant to ceftazidime and cefotaxime, among which 38 (56. 71%) cases were recognized as ESBL producer. Moreover, 7. 89% of ESBL producer isolates contained blaTEM gene. In 94 isolates collected from Khoy, 24 (25. 53%) resistant isolates to ceftazidime and 25 (26. 5%) isolates resistant to cefotaxime were recovered. Among β-lactam resistant isolates of Khoy, 24 (52. 12%) ESBL producer were obtained, of which 12. 5% contained blaTEM gene. ِDetecting this type of resistance using molecular methods coupled with phonotypic methods and taking control of antibiotic is considered essential.