Epidermal dysplasia is a hereditary skin disease characterized by severe inflammation. It is seen primarily in the West Highland White Terrier breed. The early age of onset of severe inflammation and itchiness rapidly progresses to chronic lesions on the abdomen, extremities, and face. With time, the lesions become hard and thick, while the skin develops a greasy appearance and foul odor. There is also iInflammation of the ears with excessive buildup of earwax. Secondary bacterial skin and lymph node infections are common. Malassezia organisms are frequently identified although they are not found in all dogs with epidermal dysplasia. While a tentative diagnosis is made from skin biopsy findings, a definitive diagnosis of epidermal dysplasia can be made only with characteristic clinical and histologic findings and can be assessed only by evaluating response after appropriate topical and systemic antimicrobial therapy.
Epidermal dysplasia is usually non-responsive to drug therapy. The prognosis is poor especially if the condition is chronic and severe secondary changes have occurred. In dogs with secondary Malassezia invasion, there may be significant improvement in itchiness and skin condition with ketoconazole (Nizoral) and twice-weekly application of topical ketoconazole (Nizoral shampoo) for 3 to 4 weeks. However, recurrence of the Malassezia infection is common. A sulfur or benzoyl peroxide formulations may also be helpful in long-term management of some cases. For cases in which the chronic skin changes have not occurred, there may be a dramatic response to oral prednisone or prednisolone. Before such therapy is used, however, allergies are to be ruled out and the side effects associated with chronic steroid therapy should be considered.
- Scott, Miller, Griffin. Small Animal Dermatology, 5th ed., Philadelphia, WB Saunders
- Nesbitt & Ackerman. Canine & Feline Dermatology, 1st ed., New Jersey, Veterinary Learning Systems