Epidermal dysplasia

What is ... ?: 

This is a disorder of abnormal development of skin cells (keratinocytes) and apparent hypersensitivity to a yeast organism (Malassezia) which is ubiquitous and does not cause problems in normal healthy skin. Affected dogs have greasy, scaly skin (seborrhea) and are intensely itchy due to the yeast infection.

How is ... inherited?: 

The mode of inheritance is unknown, but suspected to be autosomal recessive.

What does ... mean to your dog & you?: 

Signs of this condition are usually seen by 6 months of age. Initially the skin is greasy and scaly and your dog will become very itchy as secondary yeast infection develops. Over time the skin will become dark, scaly and thickened.

How is ... diagnosed?: 

A skin biopsy is necessary to make the diagnosis. This is a simple procedure, done with local anesthetic, in which your veterinarian removes a small sample of your dog's skin for examination by a veterinary pathologist. The biopsy will show characteristic changes in the skin, together with Malassezia organisms.

How is ... treated?: 

This is a frustrating condition to treat. Antifungal and antiseborrhea shampoos may be helpful, but the most difficult challenge in the management of epidermal dysplasia is keeping the yeast infections under control. Use of an antifungal drug (ketoconazole) for 30 to 45 days will usually resolve the yeast infection; your dog's itching will cease and his/her skin will be nearly normal. However often as soon as treatment stops, the yeast dermatitis returns.
Some dogs with this condition have periods of relative normalcy between flare-ups of the yeast infections, and these dogs can be treated intermittently, as necessary. In most cases unfortunately, affected dogs have virtually constant Mallassezia dermatitis and the only effective solution is regular maintenance use of ketoconazole every second or third day. Many dogs in this category are euthanized due to the expense of treatment, which will be lifelong.

Breeding advice: 

Although the mode of inheritance has not been established, dogs with this serious disorder and their close relatives (parents and siblings) should not be used for breeding.


Miller, W.H. 1995. Epidermal dysplastic disorders of dogs and cats. In J. D. Bonagura and R.W. Kirk (eds.) Kirk's Current Veterinary Therapy XII Small Animal Practice. p. 597-600. W.B. Saunders Co., Toronto.

Scott, D.W., Miller, W.H., Griffin, C.E.  1995.  Muller and Kirk's Small Animal Dermatology. pp 747.  W.B. Saunders Co., Toronto.

What breeds are affected by ... ?