Acral Mutilation Syndrome in Dogs

Acral mutilation syndrome is a hereditary disease. AMS causes progressive degeneration and abnormal development of the sensory neurons in the spinal cord and in the peripheral nerves; which will cause the loss of pain sensation in the extremities. Single or multiple limbs can be affected by the disease. The hind legs are believed to be more severely affected. 

Dogs with acral mutilation syndrome will chew, bite, lick and self-mutilate their distal extremities which may result in ulcers and fungal or bacterial infections. In severe cases, auto-amputation of digits, pads and claws can occur. Canines will continue to walk on mutilated feet without showing pain or lameness.  Motor skills, coordination, and reflexes will all appear normal.

The breed best known for acral mutilation syndrome is the Cocker Spaniel, others also affected are the German Short-Haired Pointer, English Pointer and the Miniature Schnauzer.

Acral mutilation syndrome (AMS) is a rare autosomal-recessive genetic sensory neuropathy of canines.  It causes the absence of pain sensation in the dog’s extremities and eventually leads to progressive self-mutilation.

The symptoms of AMS will vary depending on the severity of the disease. Primary symptoms of the syndrome are:

• Puppies with AMS are much smaller than their littermates without the disease
• Licking, chewing and biting at the feet, which can start as early as 3 months of age
• No pain or temperature sensation

Secondary symptoms or conditions may include:

• Bleeding
• Swollen paws
• Redness around the pads
• Nail loss
• Ulcerations on toes or feet
• Hyperpigmentation
• Abscesses
• Extensive fibrosis (scarring)
• Bacterial infection
• Fungal infection

The disease acral mutilation syndrome is an autosomal-recessive condition. This means that a dog must inherit the abnormal genes from both the parents in order to be affected by the condition. More than one puppy in the litter can be affected by the disease. If both parent dogs are clear of acral mutilation syndrome, their offspring will not inherit the condition nor will they be carriers of the disease. 

A dog that inherits only one abnormal gene from either parent will have no signs of the disease, but will be a carrier and may pass the gene on to any offspring.  It is important that breeders screen stud dogs and brood bitches with a DNA test, to prevent the birth of puppies affected with acral mutilation syndrome. A veterinarian can perform DNA testing, it is a simple cheek swab of the dog’s mouth. The sample is then sent to a laboratory for screening.

Your veterinarian will require a complete medical history of your dog.  He will ask questions regarding the existing health concerns and when the onset of the symptoms occurred.  The veterinarian will then do a physical examination. Diagnosis is usually established with a combination of tests which may include:

• Electromyography - EMG test evaluates the absence of normal nerve and muscle health; the canine will need to be sedated or may need to be placed under anesthesia for this test
• Nerve biopsies may be taken under general anesthesia
• Bloodwork and cultures will help determine if there is a bacterial or fungal infection 

Dogs that are diagnosed with acral mutilation syndrome should never be used for breeding.

Unfortunately, there is no known treatment for this disease. There are ways to prevent further mutilation such as Elizabethan collars (cones), bandages, muzzles and dog booties.  Topical application of analgesic or steroidal medication, which are bad tasting, may also help deter the pet from licking and biting the area.

Anxiolytic drugs (sedatives) such as diazepam and endorphin blockers may help the pet with anxiety. Antibiotics will be prescribed if it is established that there is a fungal or bacterial infection. Laser ablation may be suggested to help sterilize lesions and deaden nerve endings.  

Alternative medical treatments such as acupuncture or cold laser therapy may also provide some relief to your dog. If the attempts to stop the canine from further self-mutilation are unsuccessful, your veterinarian may suggest euthanasia.

There is no known cure for acral mutilation syndrome.  Routine follow-up visits to your veterinarian will be necessary to monitor how your companion is responding to any prescribed medications.  If there was a bacterial or fungal infection it will be necessary to do a recheck of the area.  It is important to contact your veterinarian if you have concerns or questions about any new symptoms that may occur.

Acral mutilation syndrome is not a life threatening disease but it will require a lifetime commitment from the pet owner to manage the conditions. If the canine does not stop self-mutilating himself, the quality of life of the pet must be considered.