Malessezia Dermatitis
(Yeast Infection of the Skin)
Yeast infections cause extremely itchy, smelly, crusty, and greasy skin. The infection usually begins
with a rash or with just some itchiness but soon progresses causing a thickening of the skin along
with the symptoms listed above. Itch from yeast infections is extremely intense and does not
respond well to treatment with steroids or antibiotics. This is because yeast is a small spore-like
form of fungi and fungal infections are not susceptible to antibiotics.
Yeast organisms are normal on the skin in small amounts. An infection is caused when skin
condition allows these organisms to overgrow. Yeast in small numbers is harmless but when you
start reaching large numbers disease and discomfort follow. The most common cause for the
overgrowth of these organisms is changes in the skin that come from allergic reactions. Often
during an allergic outbreak the skin becomes warmer and oil glands increase production in response
to the irritation. This increase in warmth and humidity causes the perfect conditions for yeast to
proliferate. Yeast infections can also occur secondarily to other disease processes. Sometimes
immune deficiencies can allow yeast infections to take hold. Also if the pet has a current bacterial
infection or highly irritated skin due to a parasite problem, yeast organisms can take advantage.
Malessezia dermatitis can be diagnosed by a number of procedures. A sample is taken from the
surface of the skin by pressing a place of clear scotch tape on the skin, rubbing the skin with a
moistened cotton swab, or sometimes by simply pressing a slide to the skin’s surface. This
sampling is then stained and looked at under the microscope where yeast is seen.
To treat yeast infection on the skin a couple different treatments can be used wither separately or
together. Topical treatment is usually our first step in fighting against the yeast. Topical treatment is
typically in the form of a medicated shampoo specially designed to kill yeast orgasms such as
pharmaseb or a chlorhexidine based shampoo. Bathing is recommended at least 2 times weekly in
the beginning of treatment and the shampoo needs to be left in contact with the skin for 10 minutes
before rinsing the pet.
Oral therapy is also needed in some cases. This involves the medication ketoconazole.
Ketoconazole is the medication that works best in treating this infection however often times the
treatment needs to be continued for several weeks and dosage can be dependant on severity of
infection and probability of recurrence.
The most important thing to realize in controlling these infections is treatment of the underlying
cause. Whether allergies, parasites, or other disease is the culprit, without them being addressed
infection in likely to return and become a persistent problem.