Sebaceous Adenitis

WHAT IS A SEBACEOUS GLAND?

Everyone has heard skin described as “dry,” “oily,” or “normal” referring to the amount of natural oil on the skin surface. The oils of the skin are important moisturizers (holding water inside the skin and preventing its evaporation). The oil also acts as a protection barrier keeping irritants or even infectious organisims off the skin cells below. Of course, at this point there is more to this covering that just skin oil; it has mixed with sweat, proteins, even the dead cells of the upper most layer of skin cells.

These oils come from the “sebaceous glands” of the hair follicle. Oils are secreted into the follicle, the small hole from which a hair grows. The oil makes its way out of the follicle and onto the skin surface and hair.

normal hair follicle

Normal hair follicle


SEBACEOUS ADENITIS MEANS INFLAMMATION OF THE SEBACEOUS GLANDS

Standard Poodle

Standard Poodle

Akita

Akita

In early stages of sebaceous adenitis skin biopsies show glands in the throes of the inflammatory process. In later stages the inflammation has more or less destroyed the glands they are absent in the biopsy sample. Knowing the stage of the disease is very important in determining what therapy will help: if the inflammation is still active, there is some chance at saving at least some of the glands.

No one knows what causes sebaceous adenitis but we know that certain breeds are predisposed (which means there is a genetic component.).

In the Standard Poodle, sebaceous adenitis is definitely a recessive genetic trait, though not all dogs with the genes for the disease will show the disease. We think a similar situation exists for the Akita. Affected dogs should be registered with the Orthopedic Foundation for Animals so that the heredity of the trait can be tracked. Other breeds that seem to have a genetic predisposition to sebaceous adenitis include the Chow Chow, Samoyed, and Viszla. Any dog breed can be affected.

 

WHAT DOES AN AFFECTED DOG LOOK LIKE?

This depends a great deal on whether the hair is short or more plush/fluffy. The condition is generally not itchy unless there is an accompanying Staphylococcal infection.

short hair Sebaceous AdenitisShort-haired dogs

 

For these breeds, a fine white dandruff begins on the head and ears which ultimately progresses to the whole body. Scaling areas have a tendency to be round or S-shaped.

 

 

 

 

fluffy Sebaceous Adenitis

Fluffy or Plush-coated dogs

 

In these breeds, the scale is most obvious as a clump of dandruff sticking to a group of hairs. The coat is dull and brittle and tends to develop a reddish tint. In time, bald spots develop. Again, usually the head is the area where problems start.

 

 

BIOPSY IS REQUIRED FOR DIAGNOSIS.

 

TREATMENT

If there is still active inflammation present then an anti-inflammatory medication such as cyclosporine or a corticosteroid such as prednisone may be able to spare some of the sebaceous glands from destruction. Nutritional supplements such as Vitamin A, zinc, omega 3 fatty acids, and Vitamin E can be helpful.

The skin oil will need to be replaced and the dandruff will need to be removed. This is generally done with an oil soak followed by a bath to strip the dandruff and excess oil or with a bath to strip the dandruff followed by a conditioning rinse.

A shampoo containing sulfur and salicylate (Sebolyt, sebolux, or one of any number of other products) can be used up to three times a week. The lather must remain on the dog for at least 10 minutes and after it is rinsed a brush can be used to remove the excess scaling. A humectant rinse such as Humilac or 75% propylene glycol or a regular conditioning rinse may be used to help the skin remoisturize.

Poodles seem to need period mineral oil soaks which mean that the oil is rubbed into the hair and allowed to soak in for an hour. It is important to keep the dog from licking the mineral oil off as it will act as a cathartic (causing diarrhea) or worse, it could be aspirated to create granulomas in the lung. (Because it is a mineral based oil, the body cannot remove it and can only wall it off inside the lung.) A degreasing shampoo or even Dawn® dishwashing liquid can be used to remove the oil soak. Poodles typically need these soaks every 1-4 weeks.

Synthetic retinoids (vitamin A derivatives) have been found to be effective but at the present time these medications are tightly regulated by the government and it is extremely difficult to obtain them for veterinary use.

There have been some cases that have been reported to respond to tetracycline combined with niacinamide (a form of vitamin B-3). If more conventional methods have failed, it may be worth asking your veterinarian about trying this one.

Page posted: 4/17/08