Ear inflammation and infection is one of the most common conditions we encounter at Vet Services, especially in dogs.
The ear is divided into three sections, the external ear, the middle ear and the inner ear. Inflammation/infection can affect any one of these three compartments separately or combined. Dr Neil Stuttle explains the cause & treatment for infections in each section of your pets ear.
Otitis externa
This is the inflammation/infection of the external ear involving the ear canal down to the ear drum. The signs of an inflamed/infected ear canal are persistent head shaking, rubbing the ear along the ground, pawing at the ear and an unpleasant smell coming from the ear. This is very common and can be caused by a number of primary factors.
In dogs these factors are:
- A Foreign body down the ear canalg. barley grass seeds which are very common over the summer months.
- Mite infection. This is more common in younger pups.
- Allergy. This is most common cause of otitis externa in dogs leading to inflammation and secondary infection. This often starts as a young dog 2-4 years old.
- Hormonal conditions. These are not that common and will generally affect older dogs e.g. hypothyroidism
In cats these factors are:
- Mite infection. This is more common in younger kittens
- Ear polyps. These are benign growths of the lining of the ear canal more commonly seen in young cats.
- This can be due to an environmental or a food allergy.
- A Foreign body down the ear. These are relatively uncommon despite how many cats like to wander and explore.
It is worth noting that infection itself is not a primary factor in ear disease. There will be an underlying primary factor that has triggered the infection.
Ear disease is complicated by a number of secondary factors. These factors either predispose the ears to problems and/or perpetuate an existing problem.
Predisposing/perpetuating factors include:
Ear conformation – e.g. droopy ears that limit air circulation. The classical example here is spaniels.
Hairy ear canals – Hair itself does not cause a problem but will hold in extra wax that is produced when there is inflammation. This can affect how effective ear drops are in getting down the ear canal. If the hair is adding to the problem it is best removed, normally by plucking. If hair is present and not adding to a problem it is best left as the process of plucking itself causes inflammation and irritation.
Wet ear canals – Dogs that swim on a regular basis are predisposed to infection due to the increased moisture content in the ear. This can be managed by regular ear cleaning with a product that contains a drying agent.
Infection – This is the most common secondary factor that perpetuates ear problems. It is often the secondary infection that is noticed first often due to the green/brown discharge and the smell that accompanies it. Bacterial and/or yeast infection can be diagnosed following a smear made from the ear discharge. These are very treatable in most cases but will recur if the underlying primary factor is not managed.
Treatment of external ear disease consists of ideally removing the primary cause. This generally consists of removing foreign objects down the ear, removing polyps and treating for mites with either ear drops or topical products. When allergy is the primary factor this cannot be cured but will need to be managed either by longer term ear drops, anti – itch medication or a hypoallergenic diet.
Middle ear disease (Otitis media)
This is inflammation/infection in the middle ear. The common cause of this is a ruptured ear drum and infection spreading from the external ear. In cats a cause can be inflammatory polyps.
The signs of middle ear disease include head tilt, loss of balance, eye twitching and nausea.
Inner ear disease (Otitis interna)
This is inflammation/infection of the inner ear. This is a rare problem in cats and dogs. The signs are similar to middle ear disease including, head tilt, loss of balance, eye twitching and nausea.
If your pet is showing signs of discomfort or you are concerned about their health please give your closest Vet Services clinic a call.
Neil Stuttle, Companion Animal Veterinarian
