Ear infections in Karachi: The frequency and antibiotic resistance of bacterial isolates

Objective: This 12-month retrospective study was undertaken to determine the frequency of ear infections in children and adults, and the sensitivity of bacterial isolates to antibiotics available for their treatment Methodology: Ear swabs of 197 subjects with ear infections were processed in a local lab with branches in key areas of Karachi City from January 2009 to December 2009. The isolates from ear discharge were identified on conventional basis and their sensitivity to 24 antibiotics was determined by the Kirby-Bauer Agar Disc Diffusion Method. Results: Among the patients, 100 were females and 97 males; infections were more common in children between 1 to 10 years. Staphylococcus aureus and Pseudomonas aeruginosa were mostly isolated among 10 bacterial species; Klebsiella pneumoniae was more often grown from female infected ears. The most effective antibiotics determined for possible empirical prescription included Pipericillin+Tazobactam, Cefoperazone+Sulbactam, Imipenam, and Fosfomycin. While Ciprofloxacin (57.7%) and Amoxyclav (36.2%) exerted transitional activity, a majority of the isolates were indifferent to Cotrimoxazole, Cefixime, Lincomycin, Doxycycline and Polymyxin B. Conclusion: The increasing resistance of causative organisms in our environment to multiple antibiotics encourages the C/S of specimens prior to drug prescription in order to reduce the chances of treatment failure and amplified antibiotic resistance. When unavoidable, however, a selection of drugs is offered for empirical preference.