What is fungal dermatitis in dogs?
Fungal dermatitis, also referred to as a yeast infection or Malessezia dermatitis, is caused by the fungus Malessezia pachydermatis.
A yeast infection, a fairly common inflammatory skin condition, occurs when the yeast that naturally resides in your pet's ears, mucocutaneous areas, and skin reproduces excessively, leading to an overpopulation in these regions.
What causes fungal skin infections?
Yeast flourishes in hot, humid environments, and infections can occur when your pet's immune system is weakened or when they are prescribed potent immunosuppressive medications. The condition can be caused by an increase in the amount of oils produced on the skin, or excess skin oils.
Yeast-like organisms or fungi can invade the circulation system and lead to problems in your dog's organs. Some of the more serious fungi that can be encountered are histoplasmosis, cryptococcus, and Valley Fever, among others.
Luckily, fungal dermatitis is not something you can catch from someone else, but it may come back if you don't take medication to control the underlying skin condition or allergy.
If you have a Cocker Spaniel, Shetland Sheepdog, Dachshund, Basset Hound, West Highland White Terrier, Silky Terrier, Maltese Terrier, Australian Terrier, Poodle, or Lhasa Apso, you should be vigilant as these breeds are more prone to yeast infections.
What are signs and symptoms of fungal dermatitis?
When harmless malassezia changes to a pathogenic form, it can become problematic and result in symptoms such as:
- Skin irritation
- Inflammation
- Intense itchiness
- Flaky, crusty or scaly skin
- Thickened/”elephant” skin
- Ear infections
You might observe these signs particularly in the areas between your pet's paw pads and nails, as well as on the neck, nasal folds, armpits, and anal area. Make sure to also check his surroundings. Secondary symptoms may manifest as a sticky discharge, skin redness, or sores.
If your dog's coat appears greasy, shows signs of hair loss, or has a foul smell, it may be an indication of an underlying health issue such as a yeast infection. It is recommended to consult a veterinarian for proper diagnosis and treatment.
How is fungal dermatitis in dogs diagnosed?
Your vet may use any of these techniques to collect a sample from your dog so his infection can be diagnosed and treated:
Skin biopsy - The most invasive diagnostic test uses a biopsy punch to obtain a small piece of skin. However, this provides the most complete diagnostic data.
Cotton swab sample - The skin is rubbed with a moistened swab to collect yeast organisms. Impression smear - A microscope slide is pressed onto the skin to collect yeast organisms. Acetate tape preparations - A piece of clear tape is applied to the skin to collect yeast organisms.
Skin scrape - The skin is scraped with a blade so yeast organisms can be collected.
How is fungal dermatitis treated?
There are a number of options for treating yeast infections in dogs, including oral or topical solutions. Sometimes your vet will prescribe a combination of both if the case is severe.
Oral Treatment
Persistent, severe or chronic cases of yeast dermatitis would require this type of treatment. In addition to the condition, bacterial skin infections may also be present and will need to be treated with antibiotics for a period of 4 to 12 weeks. Systemic anti-fungal medications, such as itraconazole, fluconazole, and ketoconazole, are commonly included in this category.
Be cautious when using these drugs as they can potentially cause side effects on your dog's liver, despite their high effectiveness. You must have routine blood tests and be closely monitored.
Topical Treatment
Using a medicated shampoo that contains benzoyl peroxide or selenium sulfide is crucial in treating yeast dermatitis. It is recommended to take a 10-minute bath with an anti-fungal shampoo after the initial cleansing session with the shampoo. You need to apply topical treatments every 3 to 5 days for 2 to 12 weeks in order to completely get rid of the infection.
Your dog may need to use a topical ointment daily if an infection is diagnosed on the ears or on a few isolated spots on the skin.
What is the prognosis for treating fungal dermatitis?
Treatment for yeast infections typically provides long-term relief, and you should experience a reduction in itching within a week of starting the prescribed treatment.
The outcome of your dog's condition will depend on how effectively these underlying issues, such as a compromised immune system or allergy, can be treated and controlled. Severe skin allergies can often lead to secondary yeast or bacterial skin infections, which may occur multiple times a year in certain dogs.
Your veterinarian can create a personalized treatment plan for your dog to effectively manage the condition.
Note: The advice provided in this post is intended for informational purposes and does not constitute medical advice regarding pets. For an accurate diagnosis of your pet's condition, please make an appointment with your vet.