What Is Lupus in Dogs?
Systemic lupus erythematosus, known as SLE or lupus, is a multi-systemic immune-mediated disease in dogs where multiple organs are affected.
An immune-mediated disease happens when the immune system—the system in charge of protecting the body and fighting off foreign substances (antigens), such as bacteria or viruses—becomes unbalanced and uncontrollable.
Instead of targeting foreign antigens, the immune system develops antibodies against its own proteins to form immune complexes.
When a dog has SLE, their body develops antibodies targeted against:
- DNA. A double-stranded molecule that contains genetic material.
- RNA. A single-stranded molecule that contains genetic material.
- Protein antigens. Cell proteins that the immune system reacts to.
These immune complexes can then become lodged in a pup’s tissues, creating more inflammation (swelling), which worsens their condition.
Symptoms shown by your dog will depend on the location of their immune complexes.
- If put in the kidney glomerulus (filtering system of the kidney), then glomerulonephritis and kidney failure will develop.
- If put in the joints, then painful and stiff joints, lameness, and muscle atrophy (wasting) can occur.
- If the red blood cells or platelets become targeted, then anemia or clotting disorders can develop, which will show as pale gums, lethargy, bruising, and bleeding from orifices (openings in the body).
While lupus is not considered a true medical emergency, it has potentially fatal complications.
If left untreated, it will end in an uncomfortable and painful death for a pup.
Discoid lupus erythematosus, or DLE, is a less-aggressive form of lupus that only affects the skin of the nose and face.
It is considered a benign variant of lupus and doesn’t progress to SLE.
Symptoms of Lupus in Dogs
In addition to lesions that affect the face (lips, nose, around the eyes, and ears), pups may experience the following symptoms of skin disease:
Nasal depigmentation (loss of color) and loss of normal texture to the nose
Erythema (redness) of the skin
Scaling and crusting of the skin
Dogs suffering from SLE may also show nonspecific symptoms, which can occur suddenly or come and go over time.
These signs are attributed to which part of the body is affected.
Unfortunately, dogs will often have multiple symptoms, such as:
Skin lesions (seen in about 50% of SLE cases), often occurring throughout the body, but the face, ears, and extremities are more often affected
Enlarged lymph nodes (under the jaw, armpits, behind the knees)
Decreased appetite or difficulty eating
Mouth ulcers and bad breath
Anemia (low red blood cell count)
Sneezing, often with blood (epistaxis)
Difficulty breathing or increased respiratory rate
Bruising and pin-point hemorrhages seen on the gums or skin (petechiae)
Causes of Lupus in Dogs
Female dogs tend to be more affected than males.
Any breed and age can develop lupus. However, it tends to develop more in middle-aged dogs of certain breeds, which suggests a genetic factor. These breeds include:
Lupus is an autoimmune disease that in many cases, happens without a known cause.
However, UV light and prolonged sun exposure may be factors.
The disease is often worsened by the sun. Some veterinarians think some cases are tied to the use of certain medications, viruses, and other environmental factors.
How Veterinarians Diagnose Lupus in Dogs
However, when all test results are analyzed together, they will provide your vet enough information to make a diagnosis.
Your vet will take notice of any symptoms your pup may have been experiencing during a physical exam. They may then recommend that your dog have bloodwork and urine testing done.
These tests look for evidence of anemia, a decreased platelet count, and protein in a dog’s urine.
Additionally, these tests will look for infectious parasites and tick-borne diseases with tick PCR (a test looking for DNA of certain ticks in a dog’s blood) or tick titer tests (a test looking for a dog’s antibody response to the offending tick antigen).
Your vet may also perform other tests that look for antibody and immune complex formation, such as:
Coombs test. This test looks at antibodies targeted against red blood cells.
ANA (antinuclear antibody test). This test looks for antibodies targeted against nuclear (DNA) antigens.
Lupus erythematosus (LE) cell test. This test looks for white blood cells that have engulfed nuclear material.
Immunofluorescence testing. This test looks for evidence of certain antibodies.
Diagnosis of DLE requires a biopsy (a test taken from a sample of the skin or tissue).
In this procedure, several samples of a dog’s skin are surgically removed (often using local sedation or general anesthesia) and analyzed by a veterinary pathologist.
In the case of SLE, biopsies of other organs along with fluid analysis of the joints, abdominal, or chest cavities may be taken.
Stitches are usually removed after a few weeks.
For some patients with a secondary skin infection, their vet may recommend that it’s treated for a few days before getting a biopsy, as pyoderma can make it harder to diagnose.
Treatment of Lupus in Dogs
Treatment includes blocking the immune system with prescription medications called immunosuppressants.
Steroids, at high doses, are the drug that’s prescribed most often and is the most effective. However, they can have many negative and unappealing side effects, such as:
Increased risk of infection
Increased risk of developing certain endocrine disorders
Bone marrow suppression, when too few blood cells are produced by the bone marrow
To minimize or avoid these side effects, other immunosuppressive drugs may be used with steroids. These include:
Topical therapies are often prescribed to a pup, though this type of treatment is more common in dogs affected with DLE. This includes ointments, shampoos, or conditioners having antibacterial, antifungal and/or steroidal properties.
Topical ointments with tetracycline-niacinamide or tacrolimus are good options, especially for localized lesions.
These ointments are often used with oral medications to decrease the dose of oral steroids a dog needs to take. Bathing your pet to remove crusts and scales can give itch relief and comfort, and it is soothing to the skin.
Sun exposure and UV light can also make lesions worse, so limit sun exposure as much as possible.
Because many dogs with lupus also suffer from secondary skin infections, antibiotics may also be prescribed. These could include:
Dogs with lupus often don’t need a change of diet or supplements, but talk with your vet about the best topicals, supplements, and diet for your dog based on their specific medical and nutritional needs.
Fatty acid supplements can help maintain the skin barrier and reduce inflammation, and prescription diets can help support dogs’ immune systems.
Recovery and Management of Lupus in Dogs
Lupus is not a curable disease in dogs.
However, dogs with DLE typically have a good prognosis. Usually, improvement in their condition is seen within eight to 12 weeks.
The prognosis for dogs affected by SLE—especially if multiple organs are affected—can be worse.
When significant complications develop, such as seizures and kidney failure, a pup’s prognosis is quite poor, and humane euthanasia may be recommended.
Lupus—both DLE and SLE—can be managed by an attentive pet parent. Pups often need lifelong medication.
It may take several months to see healing in your pup, and there may be scarring of their skin and permanent pigment loss as well as other symptoms, such as chronic kidney failure.
Once your dog is improved and symptoms have resolved, your vet may then recommend reducing the immunosuppressive drugs. This occurs so your dog can get the lowest dose that works and minimize any uncomfortable side effects.
Relapse—the return of your dog’s symptoms—may occur during this time, but it’s important not to lose hope because the long-term benefits of reducing drug therapy outweigh the risks.
Consistent and proper follow-up care with your vet is very important to lower the risk of relapse. Make sure to watch the disease and any drug side effects.
Be sure to follow all your vet’s recommendations, and do not stop the drugs suddenly or decrease the dose or frequency without talking with your vet first.
Prevention of Lupus in Dogs
Unfortunately, lupus cannot be prevented.
If your dog gets it, it is important to follow your vet’s recommendations because they can help minimize your pup’s flare-ups.
Because certain medications—including vaccines—have the potential to trigger an affected dog’s immune system, they should be given with caution, as recommended by your vet, or not at all.
Lupus in Dogs FAQs
How long will a dog with lupus live?
Dogs with lupus have a variable life expectancy. Those with DLE have a longer life expectancy than those with SLE.
About 50% of dogs will achieve long-term remission, but some dogs—especially those whose organs have been affected with kidney failure or neurologic deficits or who have adverse drug side effects—may be euthanized (about 40% of cases in the first year).
What happens if lupus goes untreated in dogs?
Both SLE and DLE carry serious and life-threatening risks if left untreated.
The symptoms that occur most definitely affect a dog’s quality of life and cause weakness and fatigue.
Treatment may pose challenges and risks depending on your pup’s health. Work with your vet to determine the best treatment and care plan for your pet and their comfortability.
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