en Clinical microbiology Clinical microbiology پژوهشي Research <div><strong>Introduction: </strong>This research was a retrospective study on the prevalence of nosocomial infections (NIs) and the associated risk factors among the patients admitted to the surgery and internal Intensive Care Units (ICU).<br> <strong>Materials and Methods:</strong> This cross-sectional descriptive study was conducted on patients admitted to ICUs over one year. Clinical data of patients, including demographic information, length of stay, underlining disease, the rate of patients with NIs and distribution of NIs sites and pathogens were collected. Univariate and multivariate logistic regression were run to determine the factors associated with NIs.<span dir="RTL"></span><br> <strong>Results:</strong> Collectively, 1018 patients were studied, including patients admitted to surgical ICU (n = 665) and internal ICU (n = 353). The incidence rate of NI in the surgical and internal ICUs was 67 (10.1%) and 96 (27.2%), respectively. The most NIs in the internal ICU were respiratory tract infections (RTI, 46.9%) and urinary tract infections (UTI, 37.5%), while the common infections in the surgical ICU were respiratory tract infections (RTI, 38.3%) and surgical-site infections (SSI, 22.0%), respectively. The major risk factors, length of stay and use of nasogastric intubation (NG tubes), were associated with NIs in both ICUs.<span dir="RTL"></span><br> <strong>Conclusion:</strong> Our results indicated that the incidence of infections in the internal ICU was more than the surgical ICU. Age, underlying diseases, the long stay, and use of ventilator and NG tube were of factors associated with NIs rate in internal ICU.</div> Nosocomial Infections, Risk factors, Intensive care units, Medical devices 32 41 http://jbrms.medilam.ac.ir/browse.php?a_code=A-10-551-1&slc_lang=en&sid=1 Majid Zare-Bidaki m.zare@live.co.uk 10031947532846007696 10031947532846007696 No Infectious Diseases Research Center, Birjand University of Medical Sciences, Birjand, Iran Elaheh Allahyari elaheh.allahyari@gmail.com 10031947532846007697 10031947532846007697 No Department of Epidemiology and Biostatistics, School of Health, Birjand University of Medical Sciences, Birjand, Iran Fatemeh Nikoomanesh g.nikoomanesh@yahoo.com 10031947532846007698 10031947532846007698 Yes Infectious Diseases Research Center, Birjand University of Medical Sciences, Birjand, Iran Azadeh Ebrahimzadeh mr14436@yahoo.com 10031947532846007699 10031947532846007699 No Infectious Diseases Research Center, Birjand University of Medical Sciences, Birjand, Iran