• Sadia Zafar Jinnah University for Women
  • Syed Baqir Shyum Naqvi Hamdard University
  • Tanveer Abbas University of Karachi
  • Faaiza Qazi1 Jinnah University for Women


Double Disc Synergy, Resistance, Broad spectrum


Objective: The present study was aimed to investigate the resistant pattern of Acinetobacter spp. against 4 broad spectrum antibiotics and the synergistic activity between 3 different combinations of antimicrobials.

Methods: For conducting research we obtained 52 sample of bacterial spp. from different infection sites of patients admitted to tertiary care hospital. The procedure was carried out in two parts. At first the Kirby Bauer Disc Diffusion Method was adopted to evaluate resistance pattern according to CLSI standards. 08 broad spectrum antibiotics were used. In second part of the study the synergistic activity between different combinations of selected antibiotics were estimated by Double Disc Synergy Method.

Results: It was evident that male patients were highly infected by Acinetobacter spp. The organism was found responsible for infecting the respiratory tract of elderly patients at high rate. Colistin and Polymixin effectively inhibited Acinetobacter spp. 98% each. On contrary, it was found to be highly resistant against β-lactam (98%). Cephalosporins, Quinolones, Aminoglycosides, Carbapenem were also proven inactive when used alone. All the isolates when subjected to DDS test. Highest synergy was observed between combinations of Fosfomycin-Polymixin (90.38%), Almost 52% isolates were successfully inhibited when the combination of Colistin and Fosfomycin was checked. However, more than 61% isolates showed the highest resistance when the Polymixin-Imipenemwere used together. However, all the tested combinations were highly effective against Acinetobacterisolates obtained from tracheal aspirate.



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Author Biography

Sadia Zafar, Jinnah University for Women



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How to Cite

Zafar, S., S. B. S. Naqvi, T. Abbas, and F. Qazi1. “SYNERGISTIC COMBINATIONS OF BROAD SPECTRUM ANTIBIOTICS AGAINST ACINETOBACTER SPP”. International Journal of Pharmacy and Pharmaceutical Sciences, vol. 7, no. 4, Apr. 2015, pp. 214-7,



Original Article(s)