Prevalence and Resistance Profile of Clinical Isolates of Acinetobacter Species from Karachi, Pakistan


  • Qurat ul Ain
  • Asma Naim
  • Asma Saeed



Acinetobacter baumannii, OXA-51, minimum inhibitory concentration, pan-drug resistant, multidrug resistant, broad-spectrum antibiotics


Acinetobacter baumannii causes a variety of infections including pneumonia, urinary tract infection, bacteremia, peritonitis etc. This organism is developing resistance to a number of antibiotics due to various intrinsic and acquired antibiotic resistance genes. The aim of the present study was to determine the prevalence of antibiotic-resistant Acinetobacter species from Karachi, Pakistan. A total of 111 strains of Acinetobacter baumannii and 8 strains of non-baumannii Acinetobacter were isolated from various hospitals of Karachi from September 2013 to December 2014. Identification of the isolates was based on the standard biochemical tests and detection of OXA-51 and OXA-23. Antibiotic resistance profile of the isolates was determined by Kirby-Bauer disc diffusion method and Minimum Inhibitory Concentration (MIC) was also determined by broth macro-dilution method. Among 111 Acinetobacter baumannii isolates, 8 were pan-drug resistant (PDR) and 103 isolates were multidrug resistant (MDR) while all non-baumannii Acinetobacter were MDR. The effective antibiotics against A. baumannii were colistin, gentamicin, trimethoprim/sulfamethoxazole and ciprofloxacin with MIC50 value 1, 256, 256, 256µg/ml, respectively. These findings strongly suggest the proper detection and reporting of PDR/MDR Acinetobacter from clinical samples and also the judicious use of broad-spectrum antibiotics is necessary to prevent the further spread of resistant strains of Acinetobacter.

Author Biographies

Qurat ul Ain

Department of Microbiology, University of Karachi, Karachi, Pakistan

Asma Naim

Department of Microbiology, University of Karachi, Karachi, Pakistan

Asma Saeed

Department of Microbiology, University of Karachi, Karachi, Pakistan