Introduction: Resistance of pathogenic organisms to countenance antibiotics has become a worldwide problem with serious consequences on the treatment of infectious diseases. The aim of this study was to evaluate antibiotic resistance and also the detection of transferred antibiotic resistance by plasmid in clinical Proteus isolates.

Materials and methods: A total of 250 urine samples were collected from patient suffered from urinary tract infection (UTI), and cultured on blood agar and MacConkey's agar. Positive cultures were diagnosed by routine microbiological and biochemical tests. Antibiotic susceptibility test was performed by disc diffusion method. The minimum inhibitory concentration (MIC) was evaluated by agar dilution method, and also antibiotic resistance mediated by plasmid was determined using transformation of plasmids to plasmid free Escherichia coli ATCC 25922 as competent cell.

Results: Among 200 samples, 120 samples (60%) were collected from female and 80 samples (40%) were isolated from males. Out of 25 species (12.5%) were diagnosed as Proteus. Al isolates were resistant to ampicillin (maximum frequency), only 16% of isolates were resistance to amikacin (minimum resistance). Totally, 66.66% of Proteus isolates harbored plasmids. All plasmid containing P. mirabilis isolates were able to transferred resistance to amoxicillin, ampicillin, while rate of resistance to other antibiotics were as amikacin (88%), gentamycin (72%), tetracycline (50%), tobramycin (48%), ceftazidime, cefotaxime (32%) and ciprofloxacin (22%).

Introduction: Recentlly, resistance to antibiotics has increased and antibiotic-resistant strains producing extended-spectrum beta-lactamases (ESBLs) have emerged among Enterobacteriaceae, mainly in Escherichia coli (E. coli). In this study we aimed to determine phenotypic and genotypic ESBL production in isolated E. coli from women with urinary tract infection (UTI).
Materials and Methods: In total, 92 E. coli isolates were collected from patients with UTI. The antimicrobial susceptibility of all E. coli isolates were investigated. Morover, Mast D68C test and polymerase chain reaction (PCR) were used for phenotypic and genotypic investigation of ESBLs in the studied isolates.
Results: Totally, 92 isolates of E. coli were investigated, among which 51 (55.4%) isolates were resistant to cefotaxime/ceftazidime. Theise resistante isolates were included in the study. Among the resistant isolates, 40 (78.4%) cases were ESBL producers. Moreover, all the 40 isolates were observed with both CTX-M-15 and CTX-M-14 resistance genes.
Conclusion: In general, high increasing prevalence of ESBL producer E. coil isolates of E. coil is a serious problem in the investigated region. Therefore, development of a rapid and simple method is essential to for the identification of various ESBL producer isolates.