Yeast Otitis In Dogs And Cats

Yeast otitis is a common condition in dogs and cats, especially those with allergic conditions such as Atopy.

The most common yeast infecting pets’ ears is Malasezzia pachydermatis. This yeast organism not only affects ears, but it can infect pets’ skin, also.

To diagnose yeast otitis we first observe abnormal material in the ear canals. The discharge itself is not diagnostic, but the presence of any material beyond a small amount of clear or lightly-colored wax in the ears is abnormal. In yeast otitis the discharge can be dark brown, almost black, to tan or even yellow.

Some veterinarians report that these ears have a “sour” or “yeasty” smell, much like a wet, dirty dishcloth.

The next step is to obtain a bit of the discharge on a cotton-tipped applicator, then transfer that material to a glass microscope slide. The slide is then subjected to three different-colored stains, rinsed, dried, then placed on a microscope for examination at high magnification.  The process is called Cytology.

Malasezzia, if present, will stain dark blue and look like “8s” or dumbbells.

Prevention of yeast otitis is pretty straightforward. The organisms like to live in a dark, warm, moist place. To make an ear inhospitable to them, keep the ears clean and dry. In addition, they prefer a high pH (low acidity) environment. The ear cleaner we like best, DermaPet Ear/Skin Cleanser, affords the ears a low pH (acidifying) effect, making it all the more difficult for yeast to abide.

How often should you clean your pet’s ears? At least once weekly, and every time he has a swim, bath, or other exposure to water. Let’s say Saturday is your regular cleaning day. Sunday afternoon you go to a friend’s house for a visit. He has a pool and your Fido jumps right in. Because he had exposure to water, it’s time for another cleaning.

For the ear-cleaning technique, click here.

Even one drop of water in the ear canal can turn a dark, warm dry environment into a dark, warm, moist environment, and that’s a perfect place for yeast to grow.

See you tomorrow, Dr. Randolph.


