Detection of NDM-۱ producing Klebsiella pneumoniae ST۱۵and ST۱۴۷ in Iran during ۲۰۱۹-۲۰۲۰

Background and Aim : Carbapenems are employed to treat infections caused by Gram-negativebacteria including Klebsiella pneumoniae. This research is aimed to perform phenotypic detectionof β-lactamases and molecular characterization of NDM-۱ positive K. pneumoniae isolates.Another objective is to investigate NDM-۱ producing K. pneumoniae among children in Iran.From ۲۰۱۹ to ۲۰۲۰, altogether ۶۰ K. pneumoniae isolates were acquired from various patients incertain Iranian hospitals.Methods : Antimicrobial susceptibility testing was performed by disk diffusion and brothmicrodilution methods. In addition, mCIM and eCIM were used to confirm the production ofcarbapenemases and metallo-beta-lactamases (MBLs), respectively. Detection of resistance genesnamely, blaNDM-۱, blaIMP, blaVIM, blaKPC, blaOXA-۴۸-like, blaCTX-M, blaSHV, blaTEM,and mcr-۱ was performed by PCR and confirmed by DNA sequencing. Multilocus sequence typing(MLST) was employed to determine the molecular typing of the strains.Results : According to the findings, the highest rate of carbapenem resistance was detected againstdoripenem ۸۳.۳% (۵۰). Moreover, ۳۱.۷% (۱۹) were resistant to colistin. Further to the above,altogether ۸۰% (۴۸) were carbapenemase-producing isolates and among them ۴۶.۷% (۲۸) of theisolates were MBL and ۳۳.۳% (۲۰) isolates were serine ?-lactamase producer. According to thePCR results, ۱۴ isolates produced blaNDM-۱. Remarkably, four blaNDM-۱ positive isolates weredetected in children. In addition, these isolates were clonally related as determined by MLST(ST۱۴۷, ST۱۵). Altogether ten blaNDM-۱ positive isolates were ST۱۴۷ and four blaNDM-۱positive isolates were ST۱۵.Conclusion : Based on the results, the emergence of NDM-producing K. pneumoniae amongchildren is worrying and hence, it is necessary to develop a comprehensive program to controlantibiotic resistance in the country.

کلیدواژه ها:

K. pneumoniae ، blaNDM-۱ gene ، carbapenem-resistance ، carbapenemase ، colistin ، metallo-β-lactamase genes