• Tahira Mansoor
  • Mohammed Ayub Musani
  • Gulnaz Khalid
  • Mustafa Kamal


Background: Chronic suppurative otitis media (CSOM) is a prevailing and notorious infection indeveloping countries causing serious local damage and threatening complications. Early and effectivetreatment based on the knowledge of causing micro organisms and their sensitivity results in goodclinical recovery and prevents from damage and complications. Pseudomonas aeruginosa is mostcommon pathogen causing CSOM in Pakistan. The objective of this study is to identify incidence ofPseudomonas aeruginosa involved in CSOM and sensitivity against commonly prescribed antibiotics.Methods: A total of 263 patients with unilateral or bilateral chronic suppurative otitis media (CSOM)were enrolled in the study at Department of ENT, Karachi Medical and Dental College & AbbasiShaheed Hospital, Karachi, Pakistan from December 2004 to May 2006. Sterile cotton swabs wereused to collect pus from discharging ears and plated on Blood agar and MacConkey agar for 24 to 48hours. Antibiotics susceptibility was tested by Minimum inhibitory concentrations (MIC) method usingMueller-Hinton agar. Results: Overall microbiology of 267 samples from 263 patients was studiedincluding 4 of bilateral discharge. Polymicrobial growth was present in 8 samples. A total of 275bacterial isolates were studied. Pseudomonas aeruginosa (40%) and Staphylococcus aureus (30.9%)were the most common bacterial agents found in CSOM. MIC was done for Pseudomonas aeruginosaonly as it was the commonest pathogen found in CSOM. Sensitivity pattern of Pseudomonasaeruginosa showed that amikacin was active against 96% of isolates followed by ceftazidime 89%,ciprofloxacin 85%, gentamicin 81%, imipenem 76%, aztreonam 42% and ceftriaxone 21%.Conclusions: Pseudomonas aeruginosa was the most common bacteria isolated from chronicdischarging ears followed by Staphylococcus aureus. Amikacin was found to be the most suitable drugfollowed by ceftazidime and ciprofloxacin for Pseudomonas aeruginosa. The resistance againstceftriaxone and aztreonam was found to be very high.Keywords: Chronic suppurative otitis media, Antibiotic resistance, Pseudomonas aeruginosa


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