Managing recurrent otitis externa in dogs: what have we learned and what can we do better?

Abstract

Recurrent otitis externa is a common problem in dogs. Topical treatment for each flare is successful in the short term, but repeated cycles of inflammation and infection lead to chronic inflammatory changes, pain and aversion, and antimicrobial resistance. These make the flares more frequent and harder to control. Eventually, the changes become irreversible and require a total ear canal ablation/lateral bulla osteotomy or ablative laser surgery. Most ear canal surgery is avoidable if recurrent otitis is properly managed at an earlier stage. This requires a different mindset and approach to these cases, taking advantage of recent research and clinical findings. Most importantly, clinicians must appreciate that all recurrent ear infections in dogs are secondary. To achieve a good long-term outcome, it is essential that all the underlying factors in each case are diagnosed and managed using the primary, secondary, predisposing, and perpetuating framework. This means that the primary condition must be diagnosed and managed, the secondary infection treated, predisposing risks identified and corrected, and the perpetuating factors reversed. Treatment is in 2 phases: induction to get the ears in remission and then long-term maintenance therapy to prevent relapses. Treatment should be appropriate to each dog but will typically involve ear cleaning, topical antimicrobial therapy, and topical or systemic glucocorticoids. Novel treatments for infection and inflammation will offer additional options in the future. Understanding the triggers for recurrent otitis in dogs will help clinicians plan effective management regimens that will make a huge difference to the quality of life of their patients and their owners.