For most of us, our animals are part of the family. But, unlike people, they cannot tell us when something is wrong, and it can be frightening when we notice symptoms of poor health in our pets.
Like us, animals have immune systems meant to protect us from foreign invaders that cause infections and diseases. However, in cases of autoimmune disease, this system malfunctions, causing serious illness as the immune system attacks itself and begins destroying healthy tissue.
Autoimmune Disease in Dogs
Autoimmune diseases vary and can affect a single organ or multiple ones. Veterinarians often use the term immune-mediated for these types of ailments. All autoimmune diseases stem from high levels of antigen-antibody complexes that form throughout the body. The white blood cells and lymphocytes attack healthy cells, tissues, and organs as they would attack diseased ones. No one knows precisely what causes this ‘switch,’ and symptoms of the disease vary widely, depending on the parts of the body affected.
Autoimmune diseases can affect connective tissues, the endocrine system (which controls hormones and naturally occurring chemicals in the body), muscles, nerves, and the skin. It is important to note that animals suffering from any autoimmunity generally should not be vaccinated unless under specific circumstances, which your vet can educate you on.
Autoimmune diseases in dogs can occur at any age, and certain breeds are predisposed.
Causes of Autoimmune Disease in Dogs
While some autoimmune diseases in dogs occur without a known reason, vets can pinpoint some to a specific trigger.
Theoretically, any type of cancer can bring about autoimmune disease. However, round-cell cancers like histiocytic sarcoma, leukemia, lymphoma, and multiple myeloma are well-known causes.
Cephalosporins, penicillins, sulfa-containing medications, and other antibiotics can cause hypersensitivity leading to immunity issues.
Veterinarians have found that certain breeds have genetic predispositions that cause their immune systems to turn on themselves more than others. For instance, Dobermans are sensitive to certain drugs, and Italian Greyhounds are more likely to develop immune-mediated polyarthritis.
Chronic infections, such as those of the heart and spinal cord, can trigger autoimmunity. Likewise, tick bites can cause Anaplasma, Babesia, Ehrlichia, Lyme (Borrelia), and Mycoplasma, all of which are known to cause immune diseases.
Other outside factors may exacerbate the issues, although not directly cause them, like ultraviolet (UV) light.
Symptoms of Autoimmune Diseases in Dogs
Depending on where the immune complexes attack, symptoms of the disease can vary widely. However, for all types, a dog will typically present as anorexic and lethargic, with a fever.
Other symptoms are dependent on the type of autoimmune disease present and which cells, tissues, or organs are affected.
Autoimmune Skin Diseases in Dogs
While relatively rare, there are numerous variations of autoimmune diseases that can affect a dog’s skin.
There is a group of five immune-mediated skin diseases in dogs that fall under the pemphigus complex. This group is characterized by the large and small blisters (vesicles and bullae) that occur around the mouth and junctions where the skin meets mucosal tissues (mucocutaneous junctions). The blisters often appear around the anus or the eyelids, lips, and nostrils.
Pemphigus Foliaceus (PF)
Known as leaf-like pemphigus, this is the most common autoimmune skin disease in dogs and cats alike. While most blisters for other forms present around the mouth and mucocutaneous junctions, this disease causes crusty scabs and ulcers around the bridge of the nose, ears, eyes, groin, and pads of the feet.
This pemphigus may form suddenly and may be drug-induced. However, certain breeds are affected more than others. Akitas, Chow-chows, Cocker spaniels, Daschunds, English bulldogs, Finish Spitzes, and Labrador retrievers are all susceptible. Some symptoms to look out for are:
- Crusty spots
- Excessive itchiness/scratching
- Hair loss
- Hyperpigmentation, typically black
- Peeling foot pads
- Pustules that form under the skin
Pemphigus Vulgaris (PV)
Pemphigus Vulgaris is known as common pemphigus, as it is the most frequent one that presents in humans but is rare in dogs. Fluid-filled blisters form in and around the anus, genitals, lips, nostrils, or mouth that break open and turn into ulcers. The condition is quite painful, and it may cause depression and loss of appetite.
Pemphigus Erythematosus (PE)
PE is known as red and inflamed pemphigus, as its typical symptom is redness and hair loss with crusty scaling around the nose. Ultraviolet light is known to exacerbate this form. Collies, German shepherds, and Shetland sheepdogs are most affected, and other symptoms to look for are excessive itching and scratching.
Pemphigus vegetans are thought to be a benign version of PV. It is rare in dogs, but it is usually in the form of oozing lumps around the groin area when it occurs. The bumps typically crust over, and you may notice what looks like warts in the area.
Paraneoplastic pemphigus (PNP)
PNP signifies an underlying malignant tumor. It is the most severe type of autoimmune skin disease, but luckily, it is extremely rare.
Other than the pemphigus complex, there are a few more skin disorders to look out for.
While pemphigoid may sound like pemphigus, the two are different. Bulbous is the term for a liquid-filled, thin-walled sac. Before and during the forming of these blisters, you will notice red welts and hives on the skin, and the dog will be itching. The sacs are often found in the armpits, groin, and mouth. The blisters rupture quickly, so it is essential to take the dog to the vet as soon as you notice them so they can be biopsied. Other symptoms are decreased appetite, depression, and fever.
Discoid Lupus Erythematosus (DLE)
Another autoimmune skin disease in dogs is discoid lupus erythematosus. Also known as ‘Collie’s nose,’ it can occur in many breeds and even in cats, albeit rarely for the latter. Besides Collies, German shepherds, Shetland sheepdogs, and Siberian huskies are most often affected. Sunlight and other UV light may trigger the condition.
DLE can transform a dog’s nose from its normal texture to smooth and shiny with a loss of pigmentation. There may be ulcers present, and it bothers some dogs while others are unaffected. However, veterinarians consider DLE relatively benign.
Non-Skin Immune-Mediated Conditions in Dogs
Now that we’ve covered the most common autoimmune skin diseases, here are the other immune-mediated issues that our canine friends can suffer from.
Systemic Lupus Erythematosus (SLE)
Systemic lupus erythematosus, more commonly known as lupus, is what many think of when they hear the term autoimmune disease. It is a prime example of a systemic version of these diseases. Also called the ‘great imitator,’ lupus can mimic many other disease states. Likewise, SLE can be acute or chronic, and the symptoms often come and go. Dogs and cats can both fall victim to lupus, and they should not be vaccinated without careful consideration. Breeds usually affected include Afghan Hounds, Beagles, Collies, German Shepherds, Irish Setters, Poodles, Old English Sheepdogs, and Shetland Sheepdogs.
One classic sign of SLE is a fever that comes and goes yet does not respond to antibiotics. In addition, issues with the blood, such as hemolytic anemia, low platelet counts (thrombocytopenia), or a low white blood count (leukopenia), can point to lupus.
Symptoms often vary as the disease progresses but may also include:
- Arthritis affecting multiple joints
- Hair loss
- Skin crusting or ulcerations
- Weight loss
Addison’s Disease (Hypoadrenocorticism)
Addison’s disease in dogs occurs when the adrenal glands are attacked. Less commonly, it can result when they are damaged by trauma or an illness like cancer. Common symptoms of hypoadrenocorticism in animals are:
- Kidney failure
- Increase in thirst and urine output
- Lack of appetite
- Muscle weakness
- Pain in the abdomen
- Weight loss
Autoimmune Hemolytic Anemia
Autoimmune hemolytic anemia, which can be present with lupus, happens when immune system antibodies attack red blood cells. Symptoms include:
- Blue, crusty, swollen, red, or ulcerated extremities
- Hemoglobin present in the blood and urine
- Swollen lymph nodes or spleen
Lymphocytic thyroiditis is when the immune system is attacking the thyroid. There are many symptoms for this, including:
- Dry eyes or fat deposits in the eye
- Hair loss
- Hyperpigmentation of skin
- Intolerance of the cold
- Muscle weakness
- Skin thinning
- Slow heart rate
When acetylcholine receptors in the muscle fall victim to immune system attacks, the condition is known as myasthenia gravis. Acetylcholine is a neurotransmitter that controls the function of muscles, so there will be muscle weakness as well as:
- Difficulty swallowing
- Disinterest in exercise
Sometimes, the dog’s immune system attacks blood platelets and inhibits clotting due to reduced thrombocytes (platelets). Known as immune-mediated thrombocytopenia, this is often a secondary condition in lupus and presents as hemorrhaging, internal bleeding, and nosebleeds.
Most people are familiar with rheumatoid arthritis, though not many know that it is also an autoimmune disease in dogs. When the immune system attacks the immunoglobulin in the body, it can cause lameness, lack of appetite, fever, and swollen joints. In addition, joint movement is often restricted or nonexistent due to the pain. They dislocate easily and often make a clicking or grating sound when being manipulated.
Diagnosis of Systemic Autoimmune Disease in Dogs
It is not easy to diagnose an autoimmune disease in dogs. Many symptoms can be attributed to conditions unrelated to the immune system, and not all dogs exhibit the same ones.
Your veterinarian will have to order a comprehensive blood panel to examine the white and red blood cells, plus look for all of the following:
- Anti-nuclear bodies
- Calcium concentration
- Creatinine level
- High blood urea
- High potassium in the plasma
- Low blood cortisol level
- Low platelet count
- Thyroid hormone level
All of these metrics will help the vet determine if there is an autoimmune disease present. For instance, a low thyroid hormone level indicates lymphocytic thyroiditis, low platelets can mean thrombocytopenia, and positive anti-nuclear antibodies would be present with lupus.
How are autoimmune diseases in dogs treated?
The severity of symptoms and type of immune-mediated disease that the dog is suffering from will determine whether he needs hospitalization or not. Fortunately, many can be treated with outpatient services. That said, severe issues like the destruction of red blood cells will require more drastic measures. The use of corticosteroids like prednisone can reduce autoimmune activity and inflammation, and secondary immunosuppressants like azathioprine, cyclosporine, or cyclophosphamide are often administered. Other treatments depend on the disease itself.
Bullous autoimmune skin disease – Immunosuppressants, limiting exposure to the sun combined with gold salt therapy are recommended.
Hemolytic Anemia and Thrombocytopenia – Either may or may not require surgical removal of the spleen and a complete blood transfusion, depending on the severity.
Hypoadrenocorticism – With this condition, the salt and water balance of the body must be restored with long-term mineral corticoid therapy, often in combination with fludrocortisone acetate.
Myasthenia Gravis – A cholinesterase inhibitor like pyridostigmine bromide will have to be injected every day.
Rheumatoid arthritis – Either antineoplastics or cytotoxic drugs will be prescribed to target the offending antibodies and attack them. In the absence of other autoimmune issues like thrombocytopenia or lupus, aspirin will likely be recommended. Gold salt therapy is promising for slowing the progression and severity of rheumatoid arthritis.
Systemic Lupus Erythematosus – Lupus will require cytotoxic drug-like cyclophosphamide.
Lymphocytic Thyroiditis – To return the thyroid to a normal functioning state, the dog will have to go through synthetic hormone replacement therapy.
Autoimmune Disease in Dogs – Recovery Prognosis
Some dogs diagnosed with the autoimmune disease live relatively healthy, long lives, while others succumb. Paying attention to your dog and getting them to the vet at the first sign of something being wrong is imperative, and the animal will likely have treatments for life, along with having to go to the veterinarian for regular checkups. Once home, making the dog comfortable, reducing exposure to sunlight, and possibly a special diet will all help.
Autoimmune Disease in Dogs FAQ
Can a dog survive an autoimmune disease?
A dog’s chance of surviving an autoimmune disease is dependent on the type and severity. Some dogs are barely affected and live long lives, while others are not so lucky.
What are the symptoms of autoimmune disease in dogs?
There are many symptoms of autoimmune disease in dogs that often mimic other conditions. Some of the more common ones are skin sores that crust over or turn into painful ulcers, lethargy, fever, bleeding, muscle weakness, being unwilling or unable to eat or exercise, and swelling.
What are the three most common autoimmune diseases?
Pemphigus foliaceous (PF), discoid lupus erythematosus (DLE), and immune-mediated thrombocytopenia are common autoimmune diseases in dogs.
What is a good diet for dogs with autoimmune disease?
The best diet for a dog suffering from an autoimmune disease includes foods that are wholesome and not chemically processed. Staying away from hormones, preservatives, and other harmful substances are highly recommended. Your vet may also advise you to go grain-free. Before starting your dog on any new diet, check with your veterinarian, as some of these diseases will have special considerations.