By Dr. Becker
Claw and claw bed diseases are relatively uncommon, affecting just over 1 percent of dogs and 2 percent of cats. However, they can lead to considerable discomfort and, though they are usually confined to the claw area, may also be a sign of systemic disease.
There are many different types of claw and claw bed diseases, ranging from an absence of claws (anonychia) to claw pain (onychalgia). Dogs and cats may also have unusually small or large claws, softening of claws, abnormally curved claws and more.
In some cases, claw variations like splitting, thickening or separation of claw structure may be due to nail trauma. In other cases, these symptoms may be a sign of bacterial or fungal infections, a systemic issue or a nailbed tumor.
The First Clue: How Many Claws Are Affected?
The number of claws affected can give a clue as to what type of claw disease your pet is experiencing. If only one claw is affected, the problem may be due to an injury, bacterial infection or tumor.
When two or more of the claws are affected, it may be due to parasitic infections, fungal disease, nutritional imbalance, vasculitis (inflammation of the blood vessels), hypothyroidism or symmetric lupoid onychodystrophy (SLO, which is an autoimmune disease that targets the claws).
Whenever you suspect something is wrong with one or more of your pet's claws, have a veterinarian do a thorough check of her paws, claws and surrounding skin. Additional testing, such as x-rays, biopsy, blood tests, skin or claw bed scraping, or bacterial or fungal cultures, may be needed to make an accurate diagnosis.
Trauma: The Most Common Cause of Claw Disease in Dogs
Physical trauma is the most common cause of claw disease in dogs and the second most common cause in cats.
Sometimes pets suffer accidental crushing injuries to the toes. Your dog may injure a claw while digging, for instance, or a claw may catch or snag on a carpet or other material. Active dogs and cats are most at risk of these types of claw injuries.
The claw may have only a minor crack or it may be completely broken off. It may (or may not) bleed. Depending on severity, your pet may need to see a veterinarian for pain relief and in some cases the fractured claw may need to be professionally removed.
Parasitic Claw Diseases
The following are some of the most common parasitic or protozoal causes of claw disease:
• Demodicosis: This is the most common parasitic nail condition and is a result of an inflammatory skin condition (a form of mange) that is caused by demodex mites that can't be seen with the naked eye.
These mites are commonly found on the skin of mammals and usually don't cause a problem.
But when an animal's immune system is weakened by illness, stress, or genetic predisposition, the mite population can grow out of control, causing skin and coat issues as well as infection and malformation of the claws.
• Hookworms: Hookworms are primarily transmitted fecal-orally to animals. Your pet may eat contaminated feces or dirt, or he might run through contaminated soil, then lick his paws and ingest the eggs in that manner.
If your pet is infected with hookworms, his claws may grow rapidly (more than 1.9 millimeters a week) or display other abnormalities.
A puppy or kitten that acquires hookworms can become lethargic, weak, malnourished and anemic. Infected adult dogs and cats may show symptoms of poor appetite, diarrhea, anemia and weight loss.
• Leishmaniasis: This parasite may lead to onychogryphosis, a condition in which the claws thicken and develop a deep curve. Your pet's claws may also become abnormally long and brittle.
Bacterial and Fungal Infections of the Claw
Bacterial infections of the claw bed are common and often result after a dog or cat has injured the claw. If the infection is not treated, it can progress into a bone infection (osteomyelitis). Your pet may also display signs of infection such as fever or depressed mood.
Some dogs with hypothyroidism have dry, flaky nails and the skin around the nails may be predisposed to secondary bacterial infections. Managing thyroid disease and the secondary infection (I recommend betadine foot soaks) is important for resolution of these nailbed infections.
When a fungal infection is present, the claws may become abnormally soft or rough (sometimes referred to as sandpaper nails). Ringworm may also be present along with hair loss, rash or skin crusts elsewhere on your pet, such as her paws and face.
If your pet has a systemic fungal infection, she may also have a fever and cough and act lethargic.
Immune-Related Causes of Claw Disease
Pemphigus is an autoimmune disease that causes watery blisters to form on the skin. Often, this is associated with blisters on and/or infection of the claw beds.
In the case of the autoimmune disease symmetric lupoid onychodystrophy (SLO), your pets' nails may slough off and then form abnormally. Multiple claws on all paws will typically be affected.
SLO is associated with chronic lameness, swollen digits, partial loss of claws, bleeding from the claws and secondary skin or claw infections. Your pet may also have a history of licking her paws or claws.
You should see an integrative veterinarian if your pet displays these symptoms or has been diagnosed with SLO. In some cases, treatment with essential fatty acids, vitamin E, niacinamide (vitamin B3) and Moringa may help.
Claw Bed Tumors and Signs Your Pet May Have Claw Disease
It's estimated that 12 percent of lesions on dog claws and claw beds are tumors. Most often, this occurs on the forelimb claws rather than the hindlimb claws. In many cases, the tumor is benign, but see your veterinarian to be sure. A biopsy may be needed for diagnosis.
Because there are so many causes of claw disease, you should seek veterinary care to find out the best treatment for your pet. In general, the following signs may indicate that your cat or dog is suffering from claw or claw bed disease:
- Licking her paws
- Difficulty walking
- Pain in the paws
- Swelling or redness around the claws
- Abnormal claw color
As mentioned, if only one claw is affected, injury is the likely cause. If multiple claws are affected, there's more likely to be an underlying disorder causing the symptoms.
One of the best ways to prevent claw injuries in your pet is to keep her claws trimmed and clean. Claws must be trimmed very carefully to avoid cutting into the quick (which could lead to infection). You can find tips for trimming your dog's or cat's claws in the videos below.