What is coonhound paralysis?
Coonhound paralysis describes a sudden, progressive paralysis in dogs and occasionally cats. The paralysis results from acute inflammation of multiple nerve roots (nerves that exit the spinal cord) as well as peripheral nerves (nerves located outside the spinal cord and brain that communicate between the nervous system and the tissues in the body including the muscles).
One of the causes of acute inflammation is an immune reaction to raccoon saliva; however, it can also occur in dogs who have not encountered a raccoon. In this case, it is called acute idiopathic polyradiculoneuritis and its cause is unknown.
In humans, a similar condition is Guillain-Barré syndrome (GBS). In GBS, the body’s immune system attacks part of the nervous system, causing tingling and weakness in the legs that progresses to the upper body and arms. In severe cases, the person becomes totally paralyzed.
Are certain breeds more susceptible?
There are no breeds that are more likely than others to develop these symptoms spontaneously. Any dog breed that tends to have contact with raccoons is potentially susceptible.
What is the typical sequence of signs and symptoms?
Signs will typically appear 7–14 days after contact with raccoon saliva through a bite or scratch (true coonhound paralysis), after receiving a vaccination, or following a gastrointestinal or respiratory infection (idiopathic polyradiculoneuritis). Other risk factors, according to some studies, are exposure to Campylobacter bacteria from consuming raw poultry or exposure to a parasitic disease called Toxoplasmosis. These dogs start with a stiff-legged gait that rapidly progresses to paralysis of all 4 legs. The nerves that connect the spinal cord and the muscles are affected. Symptoms typically progress over 4–5 days, although it can take up to 10 days for maximum symptoms to appear.
These dogs have decreased reflexes, decreased muscle tone, and can lose muscle mass. The rear legs are sometimes more severely affected than the front legs, and in dogs with severe disease, their chest muscles may be affected, causing labored breathing. The facial muscles may be affected, preventing the dog from blinking normally and leading to “dry eye” and the need to provide artificial tear treatment. Also, the dog’s bark may become altered or lost. Interestingly, most dogs with polyradiculoneuritis can still wag their tails despite their paralysis.
Is this condition painful?
While coonhound paralysis is not generally considered a painful condition, pain sensation is intact. The dog can still experience pain; however, they may not be able to express pain because of the paralysis. Alternately, the dog may become overly sensitive to pain or touch. It is important to be especially watchful for any evidence of pain or discomfort and to discuss all concerns about pain with your veterinarian.
How is coonhound paralysis treated?
Severely affected dogs may need to be treated in a hospital and monitored for difficulty breathing. If breathing problems develop, oxygen treatment may be needed for a period. In severe cases, a ventilator may be required. Most dogs are treated at home once their diagnosis is confirmed and their condition is stable.
"They will need intensive physical therapy to reduce or slow the inevitable loss of muscle mass."
Most dogs can eat and drink, but they may need to be hand-fed, at least at first. If not, a feeding tube may be necessary. They will need intensive physical therapy to reduce or slow the inevitable loss of muscle mass. Bedding needs to be well-padded, and these dogs must be turned and moved frequently to prevent pressure sores. It is important to encourage as much voluntary movement as possible to facilitate a more rapid recovery. They will need to be kept clean, as urination and defecation may be out of their control. In a hospital setting, a urinary catheter can be placed to allow the bladder to drain.
No medications are proven effective for reversing this disorder. Appropriate and effective pain medications are indicated when needed.
Are there any special considerations for these dogs? What about recovery?
Coonhound paralysis may recur in some dogs. It is important to remain in close contact with your veterinarian throughout management and recovery. A veterinary re-evaluation should be performed at least every 2–3 weeks. Respiratory paralysis, pressure sores, and inflammation of the bladder (if the dog does not urinate as frequently as usual) are all potential complications.
Most dogs recover fully from coonhound paralysis/polyradiculoneuritis. Some dogs experience mild nervous system deficits for a period of several weeks to several months. The key to recovery is good nursing care: preventing pressure sores, limiting the loss of muscle mass, appropriate pain management (when needed), and adequate nutrition to support recovery.
