Sebaceous Adenitis (SA) in Dogs

Overview of Canine Sebaceous Adenitis

Sebaceous adenitis, also known as glaucomatous sebaceous adenitis or “SA”, is an uncommon inflammatory skin disease that leads to the destruction of sebaceous glands.

Sebaceous adenitis (SA) is most common in young to middle-aged dogs (1 to 7 years of age). It is genetically inherited and runs in families of dogs. It is thought to be inherited in Poodles, Akitas, and Samoyeds. Other breeds at increased risk include Vizlas, Lhasa apso, German shepherd, and the Bernese mountain dog. It is rare in cats.

The exact cause is not known, but it may be caused by an attack of the immune system against the sebaceous glands responsible for the production of sebum (oil) on the skin. As a consequence, the skin becomes dry and scaly and loses the hair (alopecia). Some dogs may develop skin infection as a consequence of the abnormal skin oil and may become itchy because of the skin infection. Skin infections manifest with odor, papules (red bumps) and excessive shedding. In general, this condition is considered a “cosmetic” problem and does not affect the dogs overall health or lifespan.

The disease starts on top of the head and spreads to the rest of the body. It starts when dogs are one to three years of age and tends to get progressively worse with time.

Screening can be done in dogs belonging to breeds at increased risk for this disease to identify individuals carrying the disease. Biopsies taken from clinically normal skin may already reveal changes suggestive of the condition. Dogs carrying the disease should be excluded from breeding programs due to the genetic nature of this condition.

What to Watch For

These disease may appear differently in different pets. Some pets have a generalized condition while other pets have multiple but focal areas of skin affected. Signs may include:

Diagnosis of Sebaceous Adenitis in Dogs

Other skin diseases may look similar to sebaceous adenitis and must be ruled out by appropriate testing.

The final diagnosis of sebaceous adenitis is made by histopathology, so skin biopsies are normally taken. Since the changes seen with this condition may not be present in all the areas, it is important that several biopsies are taken. Stitches are places in the biopsy sites to ensure fast and proper healing.

Treatment of Sebaceous Adenitis in Dogs

There is no definite cure for this condition. Long term treatments are generally required to control this disease. However, several topical and systemic treatments can be tried to decrease the clinical signs. Control of secondary infections should be treated with antibiotic therapy.

For dogs that do not respond to retinoids, other medications may be tried. Cyclosporines (Atopica®) have been effective in a few refractory cases. This medication is immunosuppressive, which means it suppresses the reaction of the immune system, and therefore has the potential to increase the risk for bacterial infections. Your dog should be closely monitored for adverse effects including vomiting, diarrhea, liver and kidney disease.

In-depth Information on Canine Sebaceous Adenitis

Sebaceous adenitis is an inflammatory disease of the sebaceous (oil) glands leading to the destruction of the glands. Vizlas, Akitas, poodles and Samoyeds are predisposed and the exact pathogenesis has not been established. It seems to be a genetically inherited defect and young dogs are usually affected.

In Poodles, it is believed to be an autosomal recessive mode of inheritance due to the fact that 25 percent of affected dogs may be sub-clinical. Several theories have been formulated to explain this condition:

Deep skin scrapings should be done in any dog with these clinical signs to rule out demodicosis.

Diagnosis In-depth of Sebaceous Adenitis in Dogs

The early lesions include alopecia (hair loss) with excess scaling and brittle hairs. The top of the head, the dorsal planum of the nose, dorsal neck and dorsal midline are commonly affected areas.

Sebaceous adenitits has a cyclic pattern in some dogs with periods of improvement and worsening. Symptoms are slightly different according to the type of hair coat:

Diagnosis of sebaceous adenitis is made by histopathology, and several biopsies may be needed to make a final diagnosis. Biopsies should be taken from affected and non-affected skin. Subtle early lesions are most useful to document active inflammation.

Secondary bacterial infection and Malassezia dermatitis are commonly present at the time of initial evaluation. Cytology is important to determine the type and severity of the infection. Infections should be cleared before skin biopsies are taken to minimize secondary non-specific changes.

Pathological changes of the tissue vary according to the stage of the disease.

Treatment In-depth of Sebaceous Adenitis in Dogs

Treatments include anti-seborrheic shampoos, emollients, essential fatty acids, antibiotics for the secondary bacterial folliculitis, and retinoids.

Topical therapy:

Systemic Therapy:

Toxicity in animals seems to be less severe than in humans. Adverse effects include: vomiting, diarrhea, erythema, keratoconjunctivitis and stiffness.

Follow-up Care for Dogs with Sebaceous Adenitis

This condition is genetic and can be prevented by identifying affected animals and carriers and eliminating these animals from the breeding program.

This is a lifelong condition, thus chronic maintenance therapy (both topical and systemic) is necessary.