From the Urinary Catheter to the Prevalence of Three Classes of Integrons, -Lactamase Genes, and Differences in Antimicrobial Susceptibility of and Clonal Relatedness with Rep-PCR.

INTRODUCTION

is a biofilm-forming agent that quickly settles on the urinary catheters and causing catheter-associated urinary tract infections. Thus, the spread of multidrug-resistant isolates, with the ability to form a biofilm that carries integron, extended-spectrum -lactamases (ESBLs), and plasmid-mediated colistin resistance genes (), represents a severe threat to managing nosocomial infectious diseases. This study is aimed at surveying the prevalence of ESBL, integrase, and genes of , isolated from the catheter, to assess the differences in their antimicrobial susceptibility and clonal dissemination.

METHOD

Microtiter plate assay was adopted to measure biofilm formation. The antimicrobial susceptibility was assessed by the disk diffusion method. Antimicrobial resistance genes (, , , , , , , and ) were detected by PCR. All of the isolates were characterized by repetitive sequence-based PCR.

RESULT

From 385 collected catheters in patients admitted to the intensive care unit (ICU), 40 were isolated. All of the isolates could form a biofilm. spp. had intrinsic resistance to tetracycline (95%) and nitrofurantoin (92.5%), which explains the high resistance prevalence. The most widely resistant antibiotic was trimethoprim-sulfamethoxazole (75%). Thirty-three (82.5%) isolates were classified as multidrug resistance (MDR). The prevalence of and genes was 60% and 25%, respectively. In 6 (15%) isolates, both genes were detected. The most frequent ESBL gene detected in all of the isolates was . Also, no detection for and antibiotic resistance genes was reported. Rep-PCR identified 39(GTG)5 types (G1-G39) of 40 isolates that 38 isolates had unique patterns.

CONCLUSION

In this study, 82.5% of isolates were MDR with high antibiotic resistance to trimethoprim-sulfamethoxazole. The and were the most prevalent genes in the integrase and ESBL gene family. High diversity was seen in the isolates with Rep-PCR. The increasing rate of MDR isolates with a high prevalence of resistance genes could be alarming and demonstrate the need for hygienic procedures to prevent the increased antibiotic resistance rate in the future.