Tehran University of Medical Sciences Iranian Journal of Microbiology 2008-3289 4 3 2012 09 15 146 149 EN S Noorbakhsh Research Center of Pediatric Infectious Diseases, Rasoul Akram Hospital, Tehran University of Medical Sciences. M Barati Research Center of Pediatric Infectious Diseases, Rasoul Akram Hospital, Tehran University of Medical Sciences. M Farhadi Research Center for Diseases of Ear, Nose and Throat, Rasoul Akram Hospital, Tehran University of Medical Sciences. J Mousavi Research Center of Pediatric Infectious Diseases, Rasoul Akram Hospital, Tehran University of Medical Sciences. V Zarabi Research Center of Pediatric Infectious Diseases, Rasoul Akram Hospital, Tehran University of Medical Sciences. A Tabatabaei Research Center of Pediatric Infectious Diseases, Rasoul Akram Hospital, Tehran University of Medical Sciences. 2015 10 16 Background: Nosocomial rhino sinusitis causes major problems in all Intensive Care Units (ICUs). Objective: To describe incidence, epidemiologic, clinical manifestations, and microbiologic findings in ICUs admitted cases with nosocomial sinusitis. Materials and Methods: A prospective, cross sectional study done in Pediatric & Adult ICUs in Rasoul Akram Hospital; Tehran Iran (2007-2008). Para-nasal sinus computed tomography (CT) was performed in all adults with fever of unknown origin (FUO) within 48h of admission and repeated thereafter (4-7 days). Infectious sinusitis was diagnosed by microbiological analysis of sinus fluid aspirates. Results: Acute bacterial nosocomial sinusitis proved in 82% (51/ 63) of all cases. Head trauma was the most common cause (n = 22, 45%) of cases. The results of culture were positive for 45 cases (82%). Of 45 culture positives, 19 yielded Gram negative organisms (41%) and 9 (22%) gave Gram positives (S. aureous, Streptococus spp). The remainders (n = 17, 37%) consisted of mixed aerobic/anaerobic bacteria.Seven cases, were positive in gram staining of sinus drainage and these were positive in culture for S. pneumonia (n = 5), Hemophilus influenza (n = 2). The type of organisms were  not related to  Glasgow Coma Scale in cases (P = 0.3). Conclusion: Nosocomial organisms isolated were quite different from community acquired rhino sinusitis cases. Investigation of CT scan and drainage of Para-nasal sinuses would be helpful in undiagnosed FUO cases, especially in traumatic patients. Optimal treatment usually consists of removal of the tubes, mobilizing the patient, and administration the broad-spectrum antibiotics. https://ijm.tums.ac.ir/index.php/ijm/article/view/692 https://ijm.tums.ac.ir/index.php/ijm/article/download/692/461