Antibiotic Susceptibility Pattern of Gram Negative Bacilli Isolated from Different Clinical Specimens in a Tertiary Care Hospital

  • Lubna Ghazal Assistant Professor, Department of Microbiology, Wah Medical College
  • Ayaz Hussain Qureshi Professor /Head Department of Microbiology, Wah Medical College
  • Naila Iqbal Registrar Department of Microbiology, Wah Medical College
Keywords: Antibiotics, Antibiotic susceptibility, Enterobacteriaceae, Gram negative bacilli


Objective: To find out the antibiotic susceptibility pattern of gram-negative bacilli isolated from different clinical specimens received in a tertiary care hospital at Wah.
Material and Methods: This cross-sectional study was carried out to determine antibiotic susceptibility pattern of gram-negative bacilli, cultured from different clinical specimens received in POF Hospital laboratory at Wah. One hundred and forty-four clinical isolates of gram-negative rods from different clinical specimens from April 2015 to March 2016 were included in the study. All the isolates were processed by standard microbiological methods. The antibiotic susceptibility pattern was carried out by disk diffusion method as recommended by Clinical Laboratory Standard Institute guidelines (CLSI).
Results: Out of one hundred and forty-four Gram-negative bacilli, one hundred (69.44%) were from Enterobacteriaceae family and forty-four (30.56%) were from non-Enterobacteriaceae group. The commonest isolated organism was Escherichia coli (47.3%), followed by Pseudomonas aeruginosa (17.36%) and Acinetobacter baumannii (13.19%). These isolates were highly resistant to the most of the commonly prescribed antibiotics. The members of the family Enterobacteriaceae showed better sensitivity for amikacin and cefoperazone-sulbactam. Resistance rate for carbapenems was significantly high for K.pneumoniae and Proteus mirabilis. Among non-Enterobacteriaceae, P.aeruginosa showed better susceptibility for cefoperazone-sulbactam, amikacin, imipenem and meropenem. The multi-drug resistant pattern was observed for Acinetobacter.baumannii.
Conclusion: The isolates depict highly resistant patterns to available oral antibiotics as well as commonly prescribed injectable third generation cephalosporins and carbapenems. Establishment and implementation of infection control practices are required to combat this grave situation.

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