Systemic Autoimmune Disease in Dogs

Systemic autoimmune disease is rare and occurs at any age. It occurs when high levels of antigen-antibody complexes form and deposit throughout the body, attacking cells, organs and tissues as they would normally attack diseases.

Systemic autoimmune disease refers to a number of autoimmune diseases in which a dog’s immune system begins to fight itself and its own protective antibodies, attacking its cells, organs, and tissues.

Symptoms may vary widely, depending upon the location of the immune complexes. Common symptoms across all types include:

• Lethargy
• Anorexia
• Fever

Additional symptoms are specific to certain types and are distinguished by the bodily system affected.

Hypoadrenocorticism (Addisons Disease)

Occurs when antibodies attack a dog’s adrenal gland. Symptoms include:

• Muscle weakness
• Depression
• Weight loss
• Collapse and shock
• Kidney failure
• Lack of appetite
• Diarrhea
• Abdominal pain
• Increased thirst and/or urine production

Hemolytic Anemia

Occurs when antibodies attack a dog’s red blood cells. Symptoms include:

• Anemia
• Free hemoglobin in blood and urine
• Jaundice
• Lethargy
• Blue, reddened, swollen, ulcerated or crusted extremities
• Swollen lymph nodes
• Swollen spleen

Systemic Lupus Erythematous (Lupus)

Is a multiple organ autoimmune disease that occurs when antibodies attack cells, organs and tissues throughout a dog’s body. Symptoms can vary according to the disease’s progression and the sites affected although they include:

• Arthritis in multiple joints
• Hair loss
• Production of dandruff
• Skin ulcerations and crusting of extremities
• High body temperature
• Loss of appetite
• Anemia
• Weight loss

Thrombocytopenia

Occurs when antibodies attack a dog’s platelets, hindering the blood’s ability to clot properly. Can occur as a secondary condition to Systemic lupus erythematosus. Symptoms include:

• Hemorrhages and/or internal bleeding
• Nosebleeds

Myasthenia Gravis

Occurs when antibodies attack acetylcholine receptors in your dog’s muscles. Acetylcholine is the neurotransmitter that controls muscle function. Symptoms include:

• Muscle weakness
• Fatigue
• Disinterest in exercise
• Difficulty swallowing
• Regurgitation of food

Rheumatoid Arthritis

Occurs when antibodies attack immunoglobulin G, which regulates your dog’s circulation. Symptoms include:

• Lameness
• Elevated body temperature
• Lack of appetite
• Swollen joints
• Restricted or nonexistent joint movement
• Dislocated joints
• A clicking, cracking or grating sound when joints are manipulated

Lymphocytic Thyroiditis

Occurs when antibodies attack your dog’s thyroid. Symptoms include:

• Hair loss
• Thinning skin
• Muscle weakness
• Slow heart rate
• Constipation
• Vomiting
• Diarrhea
• Dry eye
• Hyperpigmentation of skin
• Dandruff
• Lethargy
• Obesity
• Cold intolerance
• Fat deposits in the corner of the eye

Bullous Autoimmune Skin Disease

Occurs when antibodies attack your dog’s skin. Subsets and their symptoms are as follows:

• Pemphigus Vulgaris
• Erosions/ulcers around orifices which secrete discharge and crust over
• Depression
• Lack of appetite
• Pemphigus Foliaceus
• Pustules under skin surface
• Crusting
• Dandruff
• Loss of hair
• Excessive itchiness/scratching
• Hyperpigmentation, typically black in color
• Peeling foot pads
• Often found in the head and nose
• Pemphigus Vegetans
• Pustules
• Crusting
• Formation of papilloma, what looks like small warts
• Often found in groin area
• Pemphigus Erythematosus
• Sores secreting discharge
• Crusting
• Excessive itchiness/scratching
• Often found around the eyes, ears, and bridge of the nose
• Bullous Pemphigoid
• Erosions/ulcers around orifices which secrete discharge and crust over
• Depression
• Lack of appetite
• High body temperature

Breeds Affected

• Autoimmune Haemolytic Anemia
• Breeds - most often found in Cocker Spaniel, Old English Sheepdog, and Poodle breeds
• Gender - Is more often found in female than male dogs
• Autoimmune Thrombocytopenia
• Breeds - most often found in the Poodle breed
• Gender - Is more often found in female than male dogs
• Systemic Lupus Erythematosus
• Breeds - most often found in German Shepherd and Poodle breeds
• Rheumatoid Arthritis
• Breeds - most often found in toy breeds

There is no identifiable cause of systemic autoimmune disease. While not a cause, ultraviolet light can exacerbate the disease.

Diagnosis of systemic autoimmune disease is difficult, as all dogs don’t exhibit the same symptoms, and many symptoms overlap with other diseases.

The veterinarian will conduct a comprehensive blood panel measuring complete blood count in order to measure red and white blood cells and determine if your dog has a low platelet count, low blood cortisol, and blood chemistries in order to determine if your dog tests positive for anti-nuclear antibodies, thyroid hormone levels, high plasma potassium concentrations, high calcium concentrations, high blood urea and creatinine. These blood metrics will determine if you dog has a systemic autoimmune disease, and if so, what type. For instance, a positive anti-nuclear antibodies test indicates lupus, a low platelet count indicates thrombocytopenia, low thyroid hormone level indicates lymphocytic thyroiditis.

Your dog may or may not require hospitalization, depending on the severity of the symptoms. In cases of extreme red blood cell destruction, your dog will need to be hospitalized in order to manage red blood cell levels. However, in many situations, the disease can be treated on an outpatient basis. Corticosteroids like prednisone are prescribed to decrease inflammation and autoimmune activity. Often, this will be supplemented with a secondary immunosuppressant, such as azathioprine, cyclophosphamide or cyclosporine. Additional treatment will depend upon the type of autoimmune disease.

• Hypoadrenocorticism - Requires long-term mineralcorticoid therapy, likely with fludrocortisone acetate, in order to restore salt and water balances.
• Hemolytic Anemia and Thrombocytopenia - May or may not require a blood transfusion and surgical removal of your dog’s spleen.
• Myasthenia Gravis - Requires cholinesterase inhibiters, such as pyridostigmine bromide, injected daily.
• Rheumatoid arthritis - Requires aspirin, only in the absence of lupus and thrombocytopenia. Additionally, your dog will be prescribed cytotoxic drugs (or antineoplastics), which target and attack the dangerous antibodies. Common cytotoxics include azathioprine and cyclophosphamide. An additional tactic may be gold salt therapy, which helps to reduce further inflammation and slow progression of the disease.
• Systemic Lupus Erythematous (Lupus) - Requires cytotoxic drugs, such as azathioprine and cyclophosphamide.
• Lymphocytic Thyroiditis - Requires synthetic thyroid hormone replacement therapy to return to normal thyroid functioning.
• Bullous Autoimmune Skin Disease - Requires cytotoxic drugs azathioprine or cyclophosphamide, gold salt therapy, and limiting exposure to sunlight. Autoimmune skin diseases are exacerbated by ultraviolet light.

Prognosis of dogs with systemic autoimmune disease varies widely, with some dogs dying of complications and others living a relatively healthy life with treatment. However, treatment will likely be necessary for your dog’s entire life. You must monitor you dog carefully for symptoms of side effects, and the veterinarian will likely require frequent checkups in order to make sure the treatment is appropriate. The frequency of checkups will likely decrease over time.

When you dog comes home, it is important to provide a comfortable, quiet space for recovery, possibly in a cage, until your dog is healthy enough to move around more. Continue to be aware of your dog’s exposure to sunlight, limiting outdoor exercise to dawn and twilight times. Other specific treatments will require additional precautions. For instance, in the case of kidney complications, the veterinarian will likely prescribe a specific diet.