^Ears

Knowledge of the bacterial species present when dealing with an infectious condition will be very helpful in selecting an appropriate antimicrobial and therefore culture and sensitivity testing is often indicated. If this information is not available, a combination of cytology and a knowledge of which pathogens are likely for a given situation may help in selecting an appropriate antimicrobial. Some sites of infection have predictable common bacterial species, for example Staphylococci in canine pyoderma.³ Knowledge of the site of infection may also suggest whether bacteria are likely to be aerobic or anaerobic, for example abscesses are likely to involve obligate and facultative anaerobes.³

 

Suggested topical antimicrobials for ear infections*

Aminoglycoside^3,20,77,83

Polymixin^3,77,83

Fluoroquinolones^3,77,83

Chloramphenicol³

Ticarcillin³

Fusidic acid⁸³ for Staphylococci⁷⁷

(Clotrimazole, miconazole and nystatin for Malassezia spp.)⁷⁷

 

It is suggested that the more potent broad spectrum antimicrobials such as gentamicin and chloramphenicol should not be used as first line treatments.⁷⁸ Antimicrobial treatment should be combined with use of an appropriate antibacterial ear cleaner⁸³ and culture and sensitivity testing should be carried out where Pseudomonas aeruginosa infection is suspected.

 

Common pathogens

Staphylococcus pseudointermedius^3,20

Malassezia spp.³

Streptococcus spp.²⁰

Pseudomonas aeruginosa^3,9,20

Proteus spp.^3,20

 

*Suggested antimicrobials are based on references from scientific literature and may not necessarily reflect UK market authorisations for the relevant species or condition. Veterinary surgeons are advised to carefully check the Summary of Product Characteristics (SPC) before prescribing a product.