مقالات پذیرفته شده در هفتمین کنگره بین المللی زیست پزشکی
Characterization of Disinfectant Susceptibility Patterns in Serratia marcescens isolates Collected from Hospitals in Ardabil province, Iran
Characterization of Disinfectant Susceptibility Patterns in Serratia marcescens isolates Collected from Hospitals in Ardabil province, Iran
Kazem Nejati-Koshki,1,*Malek Namaki Kheljan,2Zohreh Neyestani,3solmaz basirikhiavi,4
1. Pharmaceutical Sciences Research Center, Ardabil University of Medical Sciences 2. Department of Microbiology, School of Medicine, Ardabil University of Medical Sciences, Ardabil, Iran. 4. Department of Microbiology, School of Medicine, Ardabil University of Medical Sciences, Ardabil, Iran.
Introduction: Antimicrobial biocides are extensively used for a long period to control hospital-acquired infections worldwide. Prolonged exposure of bacteria could promote development of resistance to antimicrobial biocides. The aim of this study was to evaluate the antimicrobial activity of four commonly used biocides i.e. triclosan, chlorhexidine digluconate, benzalkonium chloride and formaldehyde against Serratia marcescens isolates and to determine the prevalence of biocide tolerance related genes including qacE, qacED1, emrA, aceI, and fabI.
Methods: A total of 100 clinical isolates of Serratia marcescens were included in current study. The minimum inhibitroy concentrations (MICs) of antimicrobial biocides were measured using agar dilution method. Genes involved in the resistance to biocides were investigated by PCR method.
Results: The benzalkonium chloride MICs ranged between 32 -128 μg/mL, chlorhexidine digluconate 8 - 64 μg/mL, triclosan 1-32 μg/mL and formaldehyde 128 μg/mL. Overall, the highest MIC90 value was identified for formaldehyde (128 μg/mL) followed by benzalkonium chloride and chlorhexidine digluconate (64 μg/mL for each one) and triclosan 4 μg/mL.
In present study, the qacE, qacED1, emrA, aceI and fabI genes were found in 91%, 55%, 100%, 88% and 82% of isolates, respectively. The qacG gene was not identified in our Serratia marcescens isolates. A significant association (P < 0.05) was observed between MICs of benzalkonium chloride and chlorhexidin with qacE and aceI genes. The presence of fabI gene was conversely associated with triclosan elevated MICs.
Conclusion: The results of this study indicated that triclosan was the most effective biocide against Serratia marcescens.