Determination of the Frequency of CTX-M Gene in Extended Spectrum β Lactamases (ESBLs) Producing Pseudomonas aeruginosa in Clinical Samples in Ahvaz Taleghani Hospital, 2015 (Iran)

Pseudomonas aeruginosa is an important pathogen in clinical infections, which has different mechanisms of antibiotic resistance. Extended spectrum β lactamases (ESBLs) are a very important mechanism of antibiotic resistance in this bacterium. The objective of this study was to determine the prevalence of CTX-M gene in ESBL-producing P. aeruginosa isolates in clinical samples.
This study was a cross-sectional study. A total of 110 isolates of P. aeruginosa were collected from clinical samples, and after verification by biochemical tests, antibiotic susceptibility testing was performed using disk diffusion method. ESBLs were combined by combined disk method, and then CTX-M gene was identified using PCR method.
All the isolates were sensitive to colistin sulphate and the highest resistance was to ceftazidime and gentamicin, 80.9% and 80%, respectively. Ninety-three isolates (84.5%) were resistant to three different classes of antibiotics. Also, 19 samples (17.3%) were producing ESBLs and 4 samples (21.1%) had CTX-M gene.
The results of this study showed high levels of antibiotic resistance in P. aeruginosa isolates, which more than ever emphasizes the need for comprehensive programs for control and treatment of this resistant pathogen.