Abstract

Introduction: The increase in antibiotic resistance due to overuse and misuse has led to changes in the primary pathogens causing otitis media and antibiotic susceptibility. Empirical antibiotic treatment may cause treatment failure or result in complications in diseases caused by antibiotic-resistant bacteria. We aimed to identify bacterial pathogens associated with ear infections and to evaluate antibacterial resistance among isolated organisms.

Methods: Ear swab samples of patients who applied to our hospital’s Ear Nose and Throat Outpatient Clinic between February 2022 and February 2023, sent to our laboratory with the preliminary diagnosis of ear infection, were examined. The study included 144 patients whose ear swab samples’ Gram staining and culture results were compatible with ear infection. Microorganisms that grew in culture were identified using conventional methods. The antimicrobial susceptibility of the isolated strains was determined using the Kirby-Bauer disk diffusion method and evaluated by the European Committee on Antimicrobial Susceptibility Testing (EUCAST) criteria.

Results: The study examined 171 external ear canal culture results from 144 patients at their first admission and 19 patients due to recurrent external ear canal discharge in later periods. Pathogenic microorganism growth was observed in 90 specimens, normal microbial flora grew in 58 specimens, and no microorganism growth was observed in 23 specimens. Staphylococcus aureus was the most common, and Pseudomonas aeruginosa was the second most common pathogen. Ampicillin resistance was the highest among the isolated Gram-negative bacteria (77.7%).

Conclusion: It is essential to monitor the frequency of causative pathogens and the rates of resistance to antimicrobial agents to start appropriate antimicrobial therapy in patients with ear infections.