Nosocomial Bacterial Infections and Their Antimicrobial Resistance Patterns in University Hospitals of Hamedan, Iran

Background: Nosocomial infections constitute a global health problem, leading to a high rate of morbidity and mortality. The aim of this study was to determine the frequency and antimicrobial resistance patterns of nosocomial infections in edu cational hospitals of Hamadan, western Iran. Methods: During a 1-year period from April 2006 to March 2007, all patients with cul ture-proven nosocomial infections from educational hospitals in Hamedan, west ern Iran were included. Nosocomial infections were defined as a culture-proven infection, which occurred more than 48h after admission in the hospital. An timicrobial susceptibility testing of isolated bacteria was performed by disc dif fusion method. Results: A total of 170 cases of culture-proven nosocomial infections were diag nosed. Most cases were in intensive care units (ICUs) (57.4%). The common sites of infection were lower respiratory tract (51.8%) and urinary tract (31.9%). Kleb siella pneumoniae, Pseudomonas aeruginosa, and Escherichia coli, were the most prevalent pathogens (32.7%, 22.9%, and 14.8% respectively). Most en terobacteriacea isolates were resistant to third generation cephalosporins. The resis tant rates to ceftriaxone were 75.5% for K. pneumoniae, and 76% for E. coli. Among P. aeruginosa isolates, 26.5% were resistant to ceftazidim, and 36% to cipro floxacin. Among S. aureus isolates, 80% were methicillin-resistant. Conclusion: The patients in the ICUs are at a higher risk of nosocomial infec-tions. The high prevalence of antimicrobial resistance in the hospitals highlights the need of further infection control activities and surveillance programs.