en Clinical Medicine Clinical Medicine مقاله پژوهشی Original Research Article <div style="text-align: justify;"><span style="font-size:16px;"><span style="font-family:Times New Roman;"><span new="" roman="" times=""><b><span style="background:#2d7f8f"><span style="color:white">Background & Objective:</span></span></b><b> </b><b>&nbsp;</b><span lang="EN"><span style="color:black">Enterobacteriaceae, a family of Gram-negative bacteria in the normal gut flora, are common human pathogens. The rising fecal carriage of carbapenemase-producing (CPE) and extended-spectrum &beta;-lactamase-producing Enterobacteriaceae (ESBL-PE) poses significant resistance to beta-lactam antibiotics. Accordingly, this study investigated the prevalence and molecular characterization of beta-lactamase genes (blaKPC, blaIMP, blaVIM, blaNDM, blaSHV, blaTEM, blaOXA, and blaCTX-M) in Enterobacteriaceae isolates from hospitalized patients in Shahriar, Iran.</span></span></span><br> <span new="" roman="" times=""><b>&nbsp;</b><b><span lang="EN-IN"><span style="background:#2d7f8f"><span style="color:white"><span style="letter-spacing:-.1pt">Materials & Methods:</span></span></span></span></b> &nbsp;<span lang="EN"><span style="color:black"><span style="letter-spacing:-.1pt">A total of 85 stool samples were collected from hospitalized patients in the ICU and general wards of Imam Sajjad Hospital, Shahriar. Bacterial isolates were identified using standard microbiological methods for identification of Enterobacteriaceae. The antibiotic susceptibility profiles of isolates were analyzed using the disk diffusion and minimum inhibitory concentration (MIC) methods based on the Clinical and Laboratory Standards Institute (CLSI) 2023 guidelines. Phenotypic detection of ESBL metallo-beta-lactamase (MBL) resistance was performed using combined disc tests with specific inhibitors. PCR amplification with specific primers was used for the detection of beta-lactamase genes including blaKPC, blaIMP, blaVIM, blaNDM, blaSHV, blaTEM, blaOXA.</span></span></span></span><br> <span new="" roman="" times=""><b><span lang="EN-IN"><span style="background:#2d7f8f"><span style="color:white">Results: </span></span></span></b><b>&nbsp;</b><span lang="EN"><span style="color:black"><span style="letter-spacing:-.1pt">From 85 samples, 19 isolates of <i>Klebsiella pneumoniae</i> (20.43%) and 66 isolates of <i>Escherichia coli</i> (79.57%) were identified. Among these, 31 isolates exhibited ESBL production, and 10 were identified as MBL [-producing isolates]. Among the 31 carbapenem-resistant or intermediate isolates, all carried the blaCTX-M gene. Additionally, 2 isolates carried the blaNDM-1 gene, and another 2 harbored the blaIMP gene. However, the blaKPC and blaVIM genes were not detected in any of the isolates.</span></span></span></span><br> <span new="" roman="" times=""><b><span style="background:#2d7f8f"><span style="color:white">Conclusion: </span></span></b><b>&nbsp;</b><span lang="EN"><span style="color:black">The blaCTX-M gene is one of the most common resistance genes in Iran. Previous studies indicate that the prevalence of antibiotic resistance in Iran is rising dramatically, which reduces the available options of antibiotics to treat severe infections in the future.</span></span></span><br> &nbsp;</span></span></div> Fecal Carriage, ESBL, Carbapenem Resistance, Escherichia coli, Klebsiella pneumonia 156 165 http://journal.zums.ac.ir/browse.php?a_code=A-10-7214-1&slc_lang=en&sid=1 Amir Hossein Omidi amirhossein_omidi@yahoo.com 5200319475328460090083 5200319475328460090083 No Department of Epidemiology and Biostatics, Research Centre for Emerging and Reemerging Infectious Diseases, Pasteur Institute of Iran, Tehran, Iran Reyhaneh Seydmohammadi reyhanehseydmohammadi@yahoo.com 5200319475328460090084 5200319475328460090084 No Department of Biochemistry and Biophysics, Faculty of Advanced Sciences and Technology, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran Mohammad Reza Mohammadi mreza_mohammadi@modares.ac.ir 5200319475328460090085 5200319475328460090085 No Department of Bacteriology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran Mina Latifian latifianmina1376@gmail.com 5200319475328460090086 5200319475328460090086 No Department of Epidemiology and Biostatics, Research Centre for Emerging and Reemerging Infectious Diseases, Pasteur Institute of Iran, Tehran, Iran Vajihe Sadat Nikbin vsnikbin@yahoo.com 5200319475328460090087 5200319475328460090087 No Department of Bacteriology, Pasteur Institute of Iran, Tehran, Iran Fereshteh Atabi feratabi.2nd.1400@gmail.com 5200319475328460090088 5200319475328460090088 No Department of Biochemistry and Biophysics, Faculty of Advanced Sciences and Technology, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran Reza Hosseini Doust rhdoust@gmail.com 5200319475328460090089 5200319475328460090089 No Department of Microbiology, Faculty of Advanced Science and Technology, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran Fereshteh Shahcheraghi shahcheraghifereshteh@yahoo.com 5200319475328460090090 5200319475328460090090 Yes Department of Bacteriology, Pasteur Institute of Iran, Tehran, Iran