Congenital Hypotrichosis in Dogs

Congenital hypotrichosis is a condition where dogs experience the loss of their hair either at birth or just a few months old. This is due to a problem in the development of their hair follicles or their not having some or all of the follicles where hair will typically grow from. The condition may impact other things in your dog like his sweat glands or his teeth. With this condition, a dog can lack some or all of his hair.

A condition where a dog will lose his hair either at birth or at a few months of age, congenital hypotrichosis is the result of missing hair follicles or follicles having not developed correctly.

This condition can present itself at birth or when your dog reaches a few months of age. Areas more likely to be hairless are the head, ears and belly of your dog. Should the hair loss be more general, typically there will be minimal hair left on your dog’s head and at the end of his tail and legs, similar to the pattern of hair growth in dogs that have been bred to be hairless. 

In many dogs, as they get older their skin will darken and can become greasy, scaly and smelly. Should your dog have pale skin, without hair he can be more sensitive to things like frostbite and sunburn.

Types 

Hypotrichosis is when there is less hair than is typical. This is more common than alopecia, which is a lack of hair. Typically, the hair loss will occur in patterns and won’t impact your dog’s extremities, though they can occur in a more general manner. The hair loss may be present at birth or first be seen when your dog is a few months old. The condition can be in association with abnormal or missing appendages or accessory organs, or with defects in teeth, claws and eyes (or other skeletal or developmental abnormalities).

Several follicle dysplasias are possible in dogs, to include color dilution alopecia, which can occur in dogs that have the coat color genotype dd. This can be seen in Doberman Pinschers, color dilute Dachshunds, Italian Greyhounds, Greyhounds and Whippets among other breeds. Dogs with this condition have a typical coat of hair at birth; however, before they are a year old they start developing folliculitis and hypotrichosis in areas of a particular color. Black hair follicle dysplasia is similar, although it occurs earlier and will only impact the black-colored parts of your dog.

Other types of follicular dysplasia include seasonal flank alopecia (found in Boxers and Airdale Terriers), woolly syndromes and post-clipping alopecia (found in Spitz-type breeds) and alopecia X (found in Pomeranians among other breeds).

How the condition is inherited has not been confirmed. It is thought that it varies, much like the condition itself does, based on the breed of dog. The condition occurs more often in male dogs, so it is thought that inheritance may be sex-linked. Dogs like the Mexican hairless dog and the Chinese crested dog have been bred to be hairless.

If your dog has displayed hair loss from birth or shortly after, your veterinarian will suspect that he has congenital hypotrichosis. He will conduct a full physical examination of your dog, as well as conduct a skin biopsy. The skin biopsy will involve a local anesthetic and your veterinarian will take a small sample from the skin of your dog that will be examined by a pathologist. Should the sample show that there are no hair follicles or that they are significantly underdeveloped, your dog will be diagnosed with congenital hypotrichosis.

There is no treatment for congenital hypotrichosis; any hair that your dog loses, whether at birth or at several months old, is permanent. Should your dog develop seborrhea, which is when his skin gets greasy and smelly, anti-seborrheic shampoos can help manage the condition.

While there is no treatment for the condition, if your dog has congenital hypotrichosis, he can still enjoy a high quality of life. Should you notice any issues with his skin over time, through using an anti-seborrheic shampoo, any symptoms your dog is experiencing can be managed. It is important that you communicate with your veterinarian to address any other possible issues your dog is experiencing so that they can be addressed.