Frequency of Extended Spectrum β-Lactamase Genes in Pseudomonas Aerugionsa Isolates from Shiraz Hospital, Iran

Nowadays، overuse of the antibiotics culminates in existence of antibiotic resistant bacteria with high frequency. Pseudomonas aeruginosa is one of the most important pathogenic bacteria because of its resistance to beta lactam antibiotics. This character in Pseudomonas aerugionsa occurs because of extended spectrum β lactamase (ESBL) genes، which carry by transposons، plasmids and mutation. Therefore، the present study aimed to evaluate frequency of existence of OXA، PER، CTX-M1، CTX-M2 and CTX-M genes in pathogenic Pseudomonas aerugionsa isolates from different hospitals in Shiraz، Iran. The pathogenic bacteria were isolated from hospitals in Shiraz during six months. Then، the isolates were identified and their antimicrobial sensitivity assessed by antibiogram test. In addition، ESBL genes in Pseudomonas aerugionsa were tested by disk double diffusion. Afterward، DNA of the isolates was extracted and the genes amplified by PCR method. Out of 728 bacteria isolated from the clinical samples obtained from the patients of the hospitals in Shiraz، 62 Pseudomonas aeruginosa isolates harbored ESBL genes. The high level resistance character of Pseudomonas aeruginosa isolates was related to erythromycin، ampicillin، tetracycline and imipenem. In additiont highest frequency of ESBL was related to OXA-10، PER-1، CTX-M1، CTX-M2 and CTX-M3. All of the antibiotic resistant genes of Pseudomonas aeruginosa located in choromosom. Hence، more investigations on ESBL genes such as OXA and the other genes in Pseudomonas areuginosa are necessary.