Backgrounds and Objectives: Despite the widespread availability of antibiotics, antibiotic resistance uropathogens are increasing. The most common mechanism of antibiotic resistance is production of extended spectrum B-lactamas (ESBL). ESBLs are derived from TEM-1 ، TEM-2 and SHV-1ancestoral plasmids. Currently, according to a variety of mutations in these plasmids, there are more than 90 types for TEM and 25 types for SHV plasmids. Materials and Methods: In this study, 146 uropathogenic Escherichia coli (UPEC) isolates were collected. Isolated organisms were identified by standard biochemical and microbial tests. Antibiotic susceptibility was examined by disc diffusion method and isolates with ESBL, were recognized. The presence of TEM and SHV plasmids in isolates were examined by PCR method. Results: According to molecular estimations, TEM and SHV plasmids would be detected in 68/1% of isolates. But, TEM and SHV plasmids were detected in 18/1% and 13/6% of isolates, Separately. It seems that a chromosomal gene of beta lactam resistance was responsible in 52/1% of samples. Conclusion: According to increase level of antibiotic resistance among UEPC isolates, complete recognition of ESBLs is necessary and also trying to understand who they affect antibiotics resistance.
Keywords: Escherichia coli, ESBL, Antibiotic resistance