Increasing antimicrobial resistance in nosocomial pathogens; multidrug-resistant extensively drug-resistant and pandrug-resistant Acinetobacter baumannii

Objective: The aim of this study was to determine the ntimicrobial susceptibility of Acinetobacter baumannii strains, which were isolated from nosocomial infections and compare the changes in resistance rates of isolates over time.\udMethods: Acinetobacter spp. strains isolated from hospitalized patients diagnosed with nosocomial infection at Cumhuriyet University Hospital between 2007 and 2011 were included in the study. Isolate identification and antibiotic susceptibility test were performed using an automated system according to the Clinical and Laboratory Standards Instituteguidelines.\udResults: In total, 454Acinetobacter spp. strains were included in this study. A. baumannii was the most frequently isolated\udAcinetobacter species. Imipenem and meropenem resistance were determined to be 31.9% and 33.7%, respectively,\udand 74.4%, 78.0%, 76.7%, 46.6%, 62.4%, 66.8%, 61.3% and 53.9% of isolates were resistant to piperacillin-tazobactam,\udceftazidime, cefepim, amikacin, gentamicin, ciprofloxacin, levofloxacin and tetracycline respectively. The resistance rates\udof multidrug-resistant (MDR), extensively drug-resistant (XDR), and pandrug-resistant (PDR) A. baumannii were 50.2%, 28.5%, and 14.0%, respectively. Changes in MDR, XDR and PDR rates over time were examined. Importantly, PDR A. baumannii have been reached dangerous levels over time. \udConclusion:A. baumannii is one of the most important pathogen, particularly in a nosocomial setting. Increasing resistance rates of this group to all antibiotics will likely lead to increased treatment failure in the future. J Microbiol Infect Dis 2014;4(1): 7-1