Sebaceous adenitis (SA) is a rare disorder in dogs that causes inflammation and eventual destruction of sebaceous glands (glands found in the hair follicles in the skin dermis).
Sebaceous glands are microscopic glands that produce an oily/waxy matter known as sebum which helps lubricate and waterproof the skin and hair as well as aid in basic immune functions. Inflammation of these sebaceous glands is known as sebaceous adenitis. Loss of the sebaceous gland leads to dysfunction of normal hair growth which results in hair loss.
The condition commonly affects young to middle aged dogs. While sebaceous adenitis can affect any breed, certain breeds are predisposed to this condition including Poodles, Akitas, and Samoyeds.
Sebaceous adenitis is primarily a cosmetic condition, i-e, it affects appearance of the dog rather than cause any general health concern.
SA is differentiated into two forms, one affecting long-coated dogs (known as granulomatous or “standard poodle” form) while the other affecting short-coated dogs.
Dogs with long-coated form of SA will typically have dull, sparse or completely absent fur. Whitish scaling of the skin (which adheres to the coat) will cause waxy, matted hair. While itching is not primarily associated with SA, it can be intense once the affected skin becomes secondarily affected with bacterial or yeast infection. Other signs include odor along the hair line, casts forming around hair shaft and clusters of skin lesions that form in certain areas of the head.
In short-coated breeds, the condition causes facial swellings, nodular skin lesions, fine dandruff which does not adhere to the coat, and a general "moth-eaten" appearance to the coat. Scaling areas have a tendency to be round or S-shaped.