Pinnal Alopecia in Dogs

With pinnal alopecia, the hair loss may be gradual or sudden, and usually follows a pattern. For example, one ear may lose hair in the exact same pattern as the other. In most cases, pinnal alopecia begins around six months to one year of age and gradually gets worse until the ears are completely bald at about eight to nine years of age. This condition does not normally cause any other side effects besides baldness and does not affect their quality of life in any way. It is more of a cosmetic condition that bothers the owner more than their dog. However, underlying conditions do need to be ruled out so it is important that you take your dog to the veterinarian as soon as you can to get him checked out.

Pinnal alopecia is baldness of the ears that is not accompanied by itching or rash. This condition usually starts in the first year of life on the outer edges of the ears and may turn the skin dark in patches as well. In some cases, pinnal alopecia can eventually (over many years) spread to the rest of the body, but this is not common. There are a few other ear conditions that can mimic pinnal alopecia such as seborrheic dermatitis, localized demodicosis, and certain endocrine disorders. The cause of pinnal alopecia is unknown, but it mostly affects Dachshunds, American or Portuguese Water Spaniels, Chihuahuas, Italian Greyhounds, Whippets, Manchester or Boston Terriers, and Miniature Poodles.

The signs of pinnal alopecia may be sudden and severe or gradual and mild. In some cases, you may not even notice the hair loss until the hair is completely gone from the ears. With pinnal alopecia, there should be no inflammation or redness and your dog usually does not seem to notice the hair loss. Some of the things you may notice are:

• Gradual or sudden thinning of hair on the ears
• Hairs become thinned out to the point of baldness
• Darkened skin of the ears where there is hair loss
• Symmetrical baldness on both ears
• Total complete baldness of the entire ear does not usually happen until your dog is older middle aged

Types

• Gradual pinnal alopecia is the most common and happens over a lengthy period of time with fur becoming sparse and thinning out
• Sudden pinnal alopecia happens quickly, with large amounts of hair falling out within a few days

The cause is unknown, but it seems to be hereditary. It is most commonly seen in:

• Dachshunds
• American or Portuguese Water Spaniels
• Chihuahuas
• Italian Greyhounds
• Whippets
• Manchester or Boston Terriers
• Miniature Poodles

To diagnose pinnal alopecia in your pet, the veterinarian will need a complete medical history and immunization records if you have them. It is also imperative that you let the veterinarian know if your dog is on any medications. A thorough physical examination is the first thing the veterinarian will do, paying special attention to the skin and hair (or lack of hair) on the ears. A skin scraping will be taken for histopathology and samples of pinnal secretions are microscopically evaluated as well.

The results should reveal short hair follicles with thin hair shafts and no other abnormalities. To make sure your dog is not suffering from some other ailment, laboratory tests need to be performed such as blood testing, urinalysis, fecal exam, and imaging. Some of the conditions that need to be ruled out include alopecia areata, demodicosis from mites, dermatophytosis (ringworm), hormone responsive dermatosis hypothyroidism, hyperadrenocorticism, and hair follicle dysplasia.

Although this condition does not seem to cause any pain, itching, or other discomfort, many pet owners prefer to try to treat pinnal alopecia. There are some herbal remedies that may be helpful but have not been proven. Some veterinarians may suggest testosterone treatment for males, to induce hair growth.

Melatonin

Giving five milligrams of melatonin by mouth daily for four to six weeks is the most common treatment recorded. However, the results have been mixed.

Testosterone

In some cases, the veterinarian may approve a small dose of methyltestosterone to stimulate hair growth. However, since the side effects of these types of anabolic steroids are serious, most veterinarians do not agree to this. Because pinnal alopecia does not cause any harm or discomfort to your dog, your veterinarian will probably suggest melatonin instead, if anything.

As stated above, pinnal alopecia usually affects the dog owner more than the dog. There is no need for treatment as it does not cause any pain or itching at all. However, if you decide to try one of these treatments, be sure to let your veterinarian know and follow up within 30 days for re-evaluation.