Comparative study of the microbial profile from bilateral canine otitis externa

Area of Science:

• Veterinary Microbiology
• Canine Infectious Diseases

Background:

• Otitis externa is a common condition in dogs.
• Bilateral cases present unique diagnostic challenges.
• Understanding microbial flora and susceptibility is crucial for effective treatment.

Purpose of the Study:

• To investigate the microbial profiles of bilateral canine otitis externa.
• To assess antimicrobial susceptibility patterns of isolated pathogens.
• To determine if microbial isolation differs between the right and left ears.

Main Methods:

• Samples from 50 dogs with bilateral otitis externa were collected over 10 months.
• Microorganisms were isolated using standard microbiological techniques.
• Antimicrobial susceptibility testing was performed on Staphylococcus intermedius isolates.

Main Results:

• All samples showed polymicrobial bacterial and/or fungal growth; no anaerobic bacteria were isolated.
• Staphylococcus intermedius and Malassezia pachydermatis were the most frequent pathogens.
• Significant differences in microbial isolation patterns were noted between the right and left ears in 68% of dogs.
• High resistance rates of S. intermedius to common antibiotics including penicillin, ampicillin, erythromycin, tetracycline, and clindamycin were observed.

Conclusions:

• Each ear in bilateral canine otitis externa should be treated as a separate unit for diagnostic and therapeutic purposes.
• Separate microbial culturing of each ear is recommended for accurate diagnosis and targeted treatment.
• The high prevalence of antibiotic resistance in S. intermedius necessitates careful selection of antimicrobial therapy.