Malassezia pachydermatis is a saprophytic yeast that is commonly found on normal and abnormal skin.  It is often difficult to ascertain if yeast organisms found on comprised skin are a primary contributor (yeast hypersensitivity) to the clinical lesions present or if they are, merely, secondary invaders (with an underlying etiology; allergic dermatitis, etc.).

Clinical Signs

  • erythema (red, inflamed skin)
  • scaling dermatitis (yellow to gray)
  • greasy surface
  • crusting
  • malodor (smells like "corn chips")
  • many dogs are poorly responsive to common therapeutics used to control pruritus such as steroids or Apoquel. A large percentage of affected animals have an underlying etiology (ie. atopic dermatitis or Malassezia hypersensitivity) which must be explored in order to resolve / control the yeast overgrowth
  • lichenification (thickened hyperplastic and hyperpigmented skin)

Diagnosis

Specific and accurate diagnosis of Malassezia Dermatitis is often difficult and may rely heavily on clinical evaluation of the cutaneous lesions. Cytology is the preferred diagnostic test over cutaneous biopsy or culture.  

Treatment  

Antifungal medications including a combination of oral (ketoconazole, fluconazole, itraconazole, or terbinafine) and topical shampoos. Many of these cases require chronic maintenance shampoo therapy to maintain the yeast population at an acceptable and non-clinical level. Some patients require long term oral medication as well to control these symptoms. 

 

Myths Abound

The most common myth perpetuated by digital media is that dietary carbohydrates will exacerbate or even cause a yeast infection. NOT TRUE!

Grain-free or low carb diets are NOT beneficial in managing yeast dermatitis. Click here to explore other myths!

 

Contributed by:  Karen Helton-Rhodes, DVM, Diplomate ACVD