What to do for prolonged cases of otitis externa

What steps should veterinarians take in the face of a prolonged otitis externa case? In an interview with dvm360, Jason B. Pieper, DVM, MS, DACVD, assistant professor at Iowa State University explains that veterinarians should determine whether the infection fully resolves or recurs, the latter of which could indicate underlying issues such as allergies, foreign bodies, or autoimmune diseases. In the interview, Pieper talks about recurrent infections, as well as nonresponsive cases, and what each scenario entails.

Below is a partial transcript which has been edited for clarity

Jason B. Pieper, DVM, MS, DACVD: So those prolonged cases of otitis externa, the chronic ones, I think it kind of depends on, does the infection go away or not? I think that's kind of the big question mark I always have, if it goes away and then it comes back, then the question is, ‘what is that underlying problem that is going on?’ You know… whether it's the allergy, the mass, foreign body, you know, autoimmune diseases, endocrinopathies—is it those that's causing it to come back again and again? Because if that's the case, those underlying problems really need to be addressed, otherwise you're going to constantly have that inflammatory cycle going again and again. So I think if it goes away, completely resolves, no signs for a month, 2 months, 3 months…then I would consider that a recurrent otitis.

Then there's the ones that just are non-responsive otitis. If it's that chronic nonresponsive otitis externa, realistically, then I worry ‘is there something deeper down in there if we’re not responding?’ You know…one of the concerns we have now is this biofilm. Is there a biofilm that's protecting that bacteria and not allowing your medications to get in there to kill it? You know, do we need to clean, break down that biofilm to actually allow the antibiotic to get in there to kill it off? So that can be a big concern with those cases….