Ear infections are one of the most common diagnosed diseases in dogs and cats. Otitis externa, meaning inflammation of the ear can cause a great deal of pain, discomfort, and stress for your dog or cat. Dogs are most often affected by bacteria or yeast, and sometimes, a combination of both. Dogs rarely get ear mites. Cats on the other hand, when suffering from ear infections, most often have ear mites. But they, too, can be diagnosed with bacteria and yeast infections.
Otitis externa develops due to a lack of oxygen flow through the ear canal. The air flow can be disrupted for a number of reasons. A dog’s ear canal has a vertical and a horizontal component. This structure predisposes dogs to ear infections as debris must work its way upward rather than straight out. Dogs that have droopy ears, excessive hair in their ears, or narrowed ear canals, have an increased chance of ear infections. Dogs that are bathed or swim regularly are also at a higher risk of developing ear infections. Breeds that are predisposed include Cocker Spaniels, Labrador Retrievers, and Poodles.
Once air is not circulating normally in the pet’s ear canal, moisture begins to accumulate leading to inflammation. The inflammation then narrows the ear canal even more exacerbating the problem. The damp, humid environment that follows is ideal for bacteria and yeast to grow in. Once the infection, along with the inflammation, settles in, it isn’t long before the pet is seen scratching at his ears, shaking his head or holding one ear tilted. Discharge and odor may be noticeable at this point.
Otits externa needs to be diagnosed and treated. There are severe complications that can arise from leaving the ear untreated. If the infection reaches the middle ear, affected animals may have a head tilt, a lack of balance, and unusual back-and-forth eye movements called nystagmus. These symptoms are called vestibular signs and represent a complication of middle ear infection. Middle ear infections can also cause paralysis of the facial nerve, leading to a slack-jawed appearance on that side of the face. The bacteria can grow from weak, easily treated bacteria, to a stronger more complicated infection that is much more difficult to treat.
Diagnosis of Otitis externa involves a complete otoscopic exam. During the exam, your veterinarian will examine the outside of the ear, the vertical and the horizontal ear canal, as well as the ear drum. Your vet is looking for possible causes and complications of having an ear infection. The vet will also collect swabs from the ear canal. This swab will be stained with a special stain and looked at under the microscope in their office. This procedure is done to determine if bacteria, yeast, inflammation, or mites are the cause of the problem and to tell how severe the infection and inflammation is.
Treatment of Otitis externa is dependent on the diagnosis. Many ear infections require drops instilled in the ear twice daily. The drops may contain antifungal, antibiotic or anti-inflammatories, depending on the cause of the infection. Many pets will be sent home with an ear cleanser that is used to dry the ears, thus eliminating to original cause of the problem. At Twin Valley Veterinary Health Services, we recommend that all dogs that are bathed or swim regularly and have had past ear infections have their ears cleaned after water activities. In severe ear infections, oral medications may also be warranted.
If you have any questions regarding the above information or any questions/concerns in general, please contact Twin Valley VHS at 745-6642.
Dr. Justin Noble DVM
Twin Valley Veterinary Health Services