Is your dog showing signs of ear discomfort?

Harry is a 17 year old poodle crossbreed and presented for ear discomfort (shaking head and scratching) of the right ear only. The ear was found to be full of a waxy residue, and the ear pinnae surface had wax crusted onto the internal surface.

The ear canal was examined, cleaned and he was commenced onto medicated ear drops which target both bacteria and yeast. These both exist on the skin in normal healthy dogs but can become a problem when humidity or trauma to the skin allows them to proliferate into larger populations – causing itching and discomfort.

He returned 1 week later for a follow up appointment – the ear looked much improved but still not 100% as there was still a little residue inflammation. The inflammation is a result of infections – and it reduces the ability of the ear to rid itself of the waxy discharge.

The following week another appointment was made to check the ear, but it had regressed and lots of purulent (pus –like )discharge was found in the ear canal. The follow appointment (after a week had lapsed) Harry was treated with a long acting antibiotic injection (convenia) as his skin had a generalised infection and the ear was resolving, although much slower than anticipated.

Cerumen is a natural lubricant and protector of the ear canal, and overproduction can be due to breed predisposition, inflamed ear canals, polyps or growths in the ear canal. In Harry’s case, there was no evidence of cerumen gland disruption in the left ear, and no obvious growths or polyps could be seen in the ear canal.

Harry was started onto a more potent steroid ointment topically onto the ear pinna surface, in addition to the previously prescribed ear ointment.

Some improvement was seen over the course of the following month but as soon as the topical ointments were stopped (even with a step down measure of reducing to every other day dosing), the ear discharge and crusting returned almost immediately.

At this point, a small bleeding mass was identified on otoscopic examination. The mass appeared to be adjacent to the tympanic membrane (ear drum) and fresh blood was seen as well as mucoid discharge. This was likely to be the cause of the ongoing ear disease (as it had been slowly growing in the ear and had only just grown large enough to be seen with the otoscope).

Harry was admitted into hospital for the day to undergo a general anaesthetic and have his right ear cleaned and suctioned and to biopsy the mass from the ear to decide what further treatments could be offered to rid his ear of the ongoing disease.

Under anaesthetic the right ear was able to be visualised completely and the remaining crusted discharge could be evacuated from the ear. The mass (approximately 7 mm in diameter and irregular in size and shape) was then easily seen. Forceps were used to grasp the mass to sample for histopathology and de-bulk it. With several attempts, the mass was largely removed and placed into formalin pots to send for laboratory analysis.

Once it had been removed, it was possible to see that the mass was likely growing through the tympanic membrane as its integrity was now compromised.

Harry was recovered from anaesthetic and sent home with the topical ear drops as the anti-inflammatory component would help with the swelling and irritation. The histopathology results revealed that Harry’s right ear mass was a ceruminous gland carcinoma – a relatively uncommon diagnosis in dogs though usually patients are between 9-11 years of age. Secondary infections and ulcerations are commonly seen and can cause more discomfort than the primary lesion.

To completely remove the mass, a total ear canal ablation would need to be performed. This is a major procedure with high risks for an older patient.

Harry is currently being treated conservatively with topical medications into the ear to prevent the area developing secondary infections and ulcerations, and to reduce the growth rate of the mass.

If you pet has an irritated ear (or two) or has an unsavoury smell, please contact us at VetHQ to make an appointment to check their aural health.