Three-Year Trend of Antimicrobial Resistance of A. baumannii: A Retrospective Study from Ardabil, Northwestern Iran

 Acinetobacter baumannii is one of the most important pathogenic bacteria causing nosocomial and opportunistic infection with the high rate of antibiotic resistance. The aim of the present work was to study the antimicrobial resistance pattern of Acinetobacter isolates recovered from patients admitted to Imam Khomeini Hospital and identifying the related risk factors. Also, in this study, the efficacy of different combined antimicrobial therapy against A. baumannii was evaluated.

In this retrospective study, a total of 108 medical records related to patients admitted to Imam Khomeini Hospital in Ardabil province from 2011 to 2013 was entered into the study. For each patient, demographic, bacterial culture, and antibiogram data were obtained and analyzed.

Results indicated that pulmonary infections were the most common clinical source of Acinetobacter infection. The highest rate of resistance (100%) was related to ceftizoxime, chloramphenicol, furazolidone, nitrofurantoin, cephalothin, cephalexin, ticarcillin, piperacillin, amoxicillin, and aztreonam followed by ceftazidime, imipenem, co-trimoxazole, ceftriaxone, cefotaxime, and cefixime (80%). The lowest rate of resistance was seen against polymyxin B, ampicillin/sulbactam and meropenem. Our results indicated that 86.9 % and 91.7% of isolates were resistant to ceftriaxone and imipenem, respectively. Since carbapenems are the drug of choice and the last-resort agent for the treatment of MDR strain of A. baumannii , this high resistance level would be a serious concern.

The epidemiological survey will be helpful in controlling infections in hospital environment and prescribing proper antimicrobial agents.