en ميکروبيولوژي Microbiology پژوهشي Research <div style="text-align: justify;"><strong>Background</strong>: Multi-drug resistant (MDR)<em> Citrobacter freundii </em>(<em>C. freundii</em>) as a causative agent of nosocomial infections is a health threat, especially in hospitals. This study was conducted to determine the prevalence of MDR <em>C. freundii,</em> considering isolation sites and a variety of utilized antibiotics.<br> <strong>Materials and Methods</strong>: In this cross-sectional study, the clinical samples of <em>C. freundii</em> strains were collected and screened using traditional bacteriological tests in Zareh Hospital, Sari City, Iran, during 2016-2017. We used disk diffusion methods to assess the susceptibility patterns of isolates according to the Clinical Laboratory Standard Institute (CLSI) guidelines.<br> <strong>Results:</strong> Out of 3248 clinical samples, <em>C. freundii</em> strains were detected in 109 samples (32.1% females and 67.9% males)<em>. </em>Susceptibility tests indicated that 89 isolates (81.65%) were MDR strains. Frequencies of MDR <em>C. freundii</em> strains were higher in the Behavioral Intensive Care Unit (BICU) (37.61%) and restoration ward (29.35%) compared with other hospital wards.<br> <strong>Conclusion</strong>: Considering the MDR <em>C. freundii</em> strains detected from burn hospital wards, it is necessary to implement prevention criteria for their eradication from burn hospitals. The results indicate the urgent need to design more practical methods for controlling infection in hospital wards.</div> Multi drug- resistant, extensively- drug resistant Citrobacter freundii, Susceptibility testing, hospital acquired infections, Burn Hospital Wards. 63 70 http://rmm.mazums.ac.ir/browse.php?a_code=A-10-893-1&slc_lang=en&sid=1 Zahra Norouzi Bazgir zahrnorozi53@yahoo.com 10031947532846009009 10031947532846009009 No Department of Medical Microbiology and Virology, Faculty of Medicine, Mazandaran University of Medical Sciences Sari, Iran; Student Research Committee, Faculty of Medicine, Mazandaran University of Medical Sciences, Sari, Iran. Bahman Mirzaei dr.bahman.m@gmail.com 10031947532846009010 10031947532846009010 Yes Department of Medical Microbiology and Virology, Faculty of Medicine, Mazandaran University of Medical Sciences Sari, Iran; Department of Medical Microbiology and Virology, School of Medicine, Zanjan University of Medical Sciences, Zanjan, Iran. Mohammad Reza Haghshenas haghshenas 2001@yahoo.com 10031947532846009011 10031947532846009011 No Department of Medical Microbiology and Virology, Faculty of Medicine, Mazandaran University of Medical Sciences Sari, Iran. Hamid Reza Goli goli 59@gmail.com 10031947532846009012 10031947532846009012 No Department of Medical Microbiology and Virology, Faculty of Medicine, Mazandaran University of Medical Sciences Sari, Iran. Ebrahim Shafaie e.shafae1986@yahoo.com 10031947532846009013 10031947532846009013 No Infectious Diseases Research Center, Birjand University of Medical Sciences, Birjand, Iran.