Ear Infections:  They can be more complicated  than you thoughtearinfection2

  Ear disease is one of the most common conditions we see in pets. The medical name for inflammation of the outer ear canal is 'otitis externa.' It is estimated that up to 20% of the dog population is affected by this disease.

The reason that the ears are often more severely affected by this generalized skin irritation than other areas of the body, is because of the environment within the ear canal. Initially the hypersensitivity or skin allergy causes a low level of inflammation which allows bacteria and yeast organisms that normally live on skin to increase in numbers. In mildly affected dogs, most areas of the skin can avoid significant organism overgrowth, but the moist and warm environment within the ear canal provides the ideal environment for these organisms to grow and therefore cause further inflammation. As the organisms increase in numbers, their presence causes further inflammation and damage to the skin, leading to a vicious cycle of deterioration.

 

 

Signs of ear disease

 Every day we see dogs who have problems with their ears. Signs of these ear problems include:earcaneldogs

•          Odor
•          Scratching or rubbing of ears and head
•          Discharge in the ears
•          Redness or swelling of the ear flap or canal
•          Shaking of the head or tilting it to one side
•          Pain around the ears
•          Changes in behavior such as depression or irritability

Causes of ear disease

 Dogs can have ear problems for many different reasons. When we see a dog with ear disease we need to think about the possibility of:

•          Allergies such as atopy or food allergies
•          Parasites - ear mites
•          Infections - bacteria and yeast
•          Foreign bodies, e.g., plant awns
•          Trauma
•          Hormonal abnormalities, e.g., hypothyroidism
•          The ear environment, e.g., excess moisture and ear anatomy

Allergies/Yeast:

 Yeast can cause severe ear problems. We usually observe a brown waxy exudate and a bad odor. Daily cleaning of the ears will help, but often these infections are difficult to treat, and special medications need to be given since antibiotics do not kill yeast. If you suspect a yeast infection in your dog’s ears, consult your veterinarian.

 

WHERE WOULD A DOG GET A YEAST INFECTION?

Yeast happily live on most normal skin as well as in ears and anal glands.To get a yeast infection, conditions on the skin surface have to change to favor of the proliferation of yeast.

The yeasts in small normal numbers are harmless but when the yeasts are present in large numbers, disease results.

So what conditions lead to a yeast proliferation? An increase in skin oils (which often occurs in an allergic flare up) would be the most common situation. Sometimes there is an immune deficiency or hormone imbalance which allows for the yeast proliferation.

 

Some animals are battling seborrhea (excessive oil production of the skin) and thus are naturally predisposed to the yeast proliferation. The most important thing to realize is that while a yeast infection is not contagious, it tends to recur unless the underlying allergy, seborrhea, or other problem is controlled. The yeast overgrowth is extremely itchy and if it can be controlled, the underlying allergy, seborrheaetc. may not be all that itchy in and of itself.

We need to be aware that in rescue dogs the reaction to Yeast as an allergic response is due to the suppression of the normal immune system due to stress on the dog from it’s life.

It needs to be understood that while antibiotics and steroids can control the bacterial infection and the inflammation the underlying allergy trigger causing the Yeast growth must be found. It is usually food.

If you suspect a food/protein allergy to be the cause of a chronic condition you may want to undertake a food elimination diet. This is a lengthy process that you will need to keep careful records and perhaps do under the supervision of a veterinary dermatologist or your general vet.

DDC cat ear mange mites

 

 

Parasites:

The ear mite, Otodectes: Some dogs are hypersensitive to the mites, however, and the resultant itching can be intense. These dogs may scratch so much they severely traumatize the ear.

 

 

Ear Environment:earbacteriayeast

Bacteria and yeast could not ask for a better environment to live in than a warm, dark, moist ear canal. Dogs with heavy, floppy ears such as Cocker Spaniels may have ear problems due to the excess moisture that builds up in their ears.

*Bostons do not typically have an environment for bacteria and yeast as accommodating as these other breeds. i.e. Spaniels, Bassets etc.

 

Diagnosis

Because there are many potential causes of ear problems, we cannot just say it is a bacterial ear infection, dispense antibiotics, and it will go away. Often, more work is needed. Your veterinarian can use an otoscope to look down into the ear canal and determine the amount of inflammation present, if the tympanic membrane (ear drum) is involved, and if there are any foreign bodies, tumors, or other potential causes of the problem. Swabs of the ear can be taken, smeared on a microscope slide, stained, and examined for bacteria, yeast, and mites. A thorough history and physical exam may help determine if this could be a hormonal, allergic, or hereditary problem. If these are suspected, further diagnostic testing would be needed. If a bacterial infection does not respond to the first antibiotic therapy, a culture and sensitivity may need to be performed to select a different antibiotic.

Treatment:

The treatment is going to depend on what caused the ear problem and what secondary conditions are there as a result.

Antibiotics:

Used for bacterial infections and antifungals for yeast infections. Glucocorticoids such as dexamethasone are often included in these preparations to reduce the amount of inflammation in the ear. Ear problems caused by a systemic disease such as a hormone abnormality or allergy must include a therapy that treats the whole dog, such as hormonal replacement or allergy testing and hyposensitization(immunotherapy).

Allergies:

Allergies are commonly treated with regular ear cleaning with an ear cleaning solution, antihistamines, and fatty acid supplements. Sometimes corticosteroids are needed. These may be given in an oral or injectable form, or they can be applied topically. Allergy testing and immunotherapy (hyposensitzation) may be the best way to cure the ear problem.

Ear mites:

Ear mites can cause a dry, dark, crumbly debris in the ear that resembles coffee grounds. For this condition, ear cleaning followed by an ear medication to kill mites will eliminate the problem, although the treatment may need to be continued over several weeks depending upon the product used.

 

Bacterial Ear Infections:

Bacterial ear infections can also have a bad odor and often have a more yellowish exudate. If it is a severe or chronic condition, ear cleaning alone will not take care of the problem and antibiotics will almost always be necessary. Again, consult your veterinarian. Ear infections of the canal, if severe, can spread to the middle and inner ear, so prompt attention to the problem is always best.

Regardless of the cause of the ear disease, we must always keep the ear canal clean.

The key to healthy ears is to keep them clean. Check your dog's ears weekly. A slight amount of waxy buildup may be present in normal ears. If your dog swims a lot, has pendulous ears, or a history of ear disease, routine cleaning (often once to three times per week) is recommended. Use the same procedure as described above. Excess hair around the ear can be clipped to allow more air flow

Remember, if your dog is showing severe discomfort, the ears have a bad smell, or the ear canals look very abnormal, do not delay in contacting your veterinarian. If your dog has a ruptured or weakened eardrum, some ear cleansers and medications could do more harm than good.

The ultimate “fix” for a chronically infected, damaged and traumatized ear is TECA surgery. The term Total Ear Canal Ablation or TECA is used to describe a procedure used to manage severe canal or middle ear disease in dogs where other methods of treatment have failed. The full name of the procedure is Total Ear Canal Ablation with Lateral Bulla Osteotomy (TECA + LBO) but most surgeons use the term TECA for convenience. earinfection1

My experience with the cycle of chronic ear infection and TECA surgery came with a rescue I fostered. He came into rescue with untreated hematoma and three types of bacteria in his right ear one being e-coli! Upon examination under anesthesia it was found that his tympanic membrane had been eaten away by the bacteria and his ear skin was so inflamed and thickened from chronic infection that it would be impossible to break the cycle of infection. His behavior around his head was very protective and that gave rise to behavior issues. This boy had been in constant pain and discomfort most of his young life. The TECA surgery was literally a life saving surgery he had to have. His condition rendered him unadoptable.

 

However, it MUST be noted, that the surgery was only part of the puzzle. Without neutralizing the allergen causing Yeast growth in his body, the other ear which had remained healthy would surely be affected. This is, in fact what started to happen shortly after the successful TECA surgery.

 

Fortunately, his condition stabilized with a low dose of prednisone in Vanectyl –P and being on a vegetarian diet. He was adopted to a lovely couple who live a quiet life in the country which was perfect for this boy. His condition remains under control and his remaining ear smells sweet as a daisy!!

 

I cannot over stress the importance of staying on top of ear infection and ear health – with this one Boston boy it was literally life or death.

 

earinfection4                                                       Here he is (you can see the thick and flopped over damaged right ear)

Sources:
http://www.willows.uk.net/specialist
http://veterinarysurgicalcenters.com
http://www.peteducation.com
http://www.marvistavet.com