Digital hyperkeratosis sounds awful -- the name is almost as big as your little Chihuahua. However, when you break it down, this is a condition of a dog's footpads. There are two types of hyperkeratosis that can affect a dog's paws, familial footpad hyperkeratosis and idiopathic nasodigital hyperkeratosis. If your Chihuahua has digital hyperkeratosis, chances are it's the second form of the condition.
The Signs of Hyperkeratosis
When a dog makes or retains too much keratinized tissue, he has hyperkeratosis. The disease presents in the footpad or on top of the nose, showing as thickened, hardened skin. The skin will be dry and rough, perhaps even cracking.
Familial Footpad Hyperkeratosis
As the name implies, familial footpad hyperkeratosis is an inherited disease, seen primarily in Kerry blue terriers, Irish terriers and dogues de Bordeaux. This form of hyperkeratosis makes its appearance in young dogs, usually by 6 months of age. Though the footpads are normal at birth, by the half-year mark, dogs with the condition develop the telltale cracked, thick footpads, affecting the entire foot. It's not unusual for a dog to become lame from skin tears and secondary infections. Though there's no known cure for this type of hyperkeratosis, the vet can help you manage it and keep your dog comfortable. A biopsy can rule out any other potential problems. Treatment focuses on regular foot soaks as directed by the vet, as well as filing the footpads to whittle away excess keratin -- similar to how you file your own nails. If the footpads are torn or infected, the dog may require a moisturizing cream as well as antibiotics.
Idiopathic Nasodigital Hyperkeratosis
As if the footpads aren't enough, hyperkeratosis can afflict a pup's nose. This form of hyperkeratosis isn't genetically predisposed, meaning your Chihuahua is a little more vulnerable to it. While the familial footpad version strikes young pups, this version commonly affects older dogs. Tear duct blockage may contribute to the condition on the nose, but there are no other illnesses that give rise to this type of hyperkeratosis. Though dogs with idiopathic hyperkeratosis are usually healthy, the vet will rule out other illnesses, such as a zinc deficiency and discoid lupus. If your Chihuahua's tear ducts are blocked, they'll be flushed. Treatment may include soaking and moisturizing his footpads. As with the inherited version of the condition, a dog's footpads can become cracked and torn, and eventually, infected; though the condition is not critical, he needs to see his vet to prevent pain and infection.
If your Chihuahua develops digital hyperkeratosis, you'll need to be aware of his footpad health. Talk to your vet to learn how to shave excess keratin that may develop on his feet. As well, have soaks and salves on hand so you can keep his pads from becoming infected. In the case of digital hyperkeratosis, a little diligence on the front side minimizes the possibility of secondary infections.