Antimicrobial Resistance of Acinetobacter Baumannii Isolated from Intensive Care Units of Isfahan Hospitals

Acinetobacter baumannii is an opportunistic Gram-negative pathogen with increasing relevance in a variety of hospital-acquired infections especially among intensive care unit patients. A. baumannii is mostly a cause of septicaemia, pneumonia and urinary tract infection following hospitalization of patients with more severe illnesses. Multidrug-resistant isolates of A. baumannii have been reported increasingly during the last decade, probably as a consequence of extensive use of antimicrobial agents. The aim of this study was to determine the antimicrobial resistance of Acinetobacter baumannii isolated from Intensive Care Units of Isfahan hospitals. In a period of one year (2009-2010) we examined 456 clinical specimens from patients in ICU departments for isolation of Acinetobacter baumannii. Then susceptibility of isolates toward antibiotics was determined by standard disk diffusion method. A total of 50 Acinetobacter baumannii isolates were cultured from urine, catheter wound, blood, and CSF. The antimicrobial patterns of isolates showed that 52% of isolates were resistant to Carbapenems (imipenem and meropenem), 66% to Ceftazidime, 64% to Amikacin, 72% to Ciprofloxacin, 90% to trimetoprim sulfametoxazol and 54% were resistant to Piperacillin-Tazobactam. 85% of isolates were resistant to two or more antibiotics. This study showed a high percentage of resistance to antimicrobial agents in Acinetobacter baumannii isolates, therefore, strategies to control the spread of multidrug-resistant strains must be designed and evaluated. In addition, new treatment regimens are clearly necessary.