Primary Idiopathic Seborrhea

Primary idiopathic seborrhea is the most common chronic keratinization disorder of dogs. Many breeds have primary idiopathic seborrhea: Basset hound, Cocker Spaniel, Dachshund, Doberman Pincher, English Springer Spaniel, German Shepherd, Irish Setter, Shar-Pei, and West Highland White Terrier.

Signs of Seborrhea

The onset of signs is usually before 2 years of age. Depending on the breed, clinical signs may range anywhere from dry scaling (seborrhea sicca), to greasy scaling (seborrhea oleosa), to scaling and greasiness with inflammation and itchiness (seborrheic dermatitis), to any combination of these clinical abnormalities.

Seborrhea sicca is characterized by accumulations of a dry, white to gray scale. The coat is usually dull and dry. Breeds predisposed to seborrhea sicca include: Doberman Pinscher, Irish Setter, German Shepherd Dog, and Dachshund.

Seborrhea oleosa is characterized by a generalized, malodorous, greasy skin and hair coat. There are accumulations of brownish-yellow, greasy material that adhere to the hair and skin. Neck, and feet are the most severely affected regions.

Frequently, there is a concurrent ear disease with excessive buildup of earwax. Breeds predisposed to seborrhea oleosa include: Basset Hound, Cocker Spaniel, English Springer Spaniel, Labrador Retriever, Shar-Pei, and West Highland White Terrier.

Dogs with seborrheic dermatitis have malodorous, greasy skin and hair coat, along with moderate to severe inflammation, bacterial folliculitis, Malassezia dermatitis, itchiness, and inflamed skin plaques. The most commonly involved areas are the external ear canals, ear skin, neck, and chest.

Diagnosis & Treatment

A definitive diagnosis of primary idiopathic seborrhea is based on age, breed, history, and clinical tests. Topical therapy is always indicated in primary idiopathic seborrhea. Mild seborrhea sicca cases will respond to frequent applications of moisturizing shampoos and rinses. Mild to moderate shampoos containing sulfur or salicylic acid may be needed to remove heavier, dry scales. Stronger degreasing agents (benzoyl peroxide, tar, sulfur, selenium sulfide) are needed to control the greasy scale, crust, and odor associated with seborrhea oleosa. Seborrhea sicca may respond partially to systemic essential fatty acids. Acitretin (1 mg/kg orally every 24 hours) has been an effective therapy for some idiopathic seborrhea problems of Cocker Spaniels, English Springer Spaniels, Irish Setters, and Golden Retrievers. Systemic antibiotic may be prescribed if there is a secondary bacterial infection.