Pemphigus in Cats
Pemphigus can best be described as an immune-mediated skin disease in cats where a cat’s own immune system begins to attack the connection between the normal layers of skin cells. While there are different types of pemphigus that involve different areas of the skin, pemphigus foliaceus (PF) affects cats most often. Pemphigus usually affects middle-aged to senior (7+ years old) cats but can affect cats of any age. Continue reading to learn about the causes, symptoms, and treatment options for cats with pemphigus.
Causes of Pemphigus in Cats
This immune-mediated disease is associated with the following:
- Autoantibodies where the body makes its own antibodies that attack healthy skin cells as if they were diseased cells.
- Exposure to sunlight
- Particular breeds seem to have a hereditary predisposition.
- Chronic inflammatory skin disease has been thought to contribute to pemphigus.
- Possible reaction to medications
Symptoms of Pemphigus in Cats
Pemphigus Foliaceus (PF)
- The skin has scales, crusts, pustules, shallow ulcers, redness, and itching
- Pads of the paws often have cracking and skin overgrowth
- Fluid-filled cysts or vesicles in the skin
- The areas most often affected include the head, ears, and footpads and eventually become generalized over the entire body
- Gums and lips can be affected
- Often the nipples and nail beds are affected in cats
- Enlarged or swollen lymph nodes, generalized swelling such as in the limbs, fever, depression, lameness (especially when the footpads are affected)
- On/off pain and itchy skin
- Secondary bacterial skin infection due to cracked/open/ulcerated skin
Pemphigus Erythematosus (PE)
- Similar signs as for PF with areas of the affected skin being localized to the head, face, and footpads
- More often, PE causes loss of color in the lips than with other forms of pemphigus.
Pemphigus Vulgaris (PV)
- The most severe form of pemphigus
- Skin ulcers that can be shallow and deep, blisters, and crusted skin
- Affected areas include gums, lips, and skin but becomes generalized over the entire body
- Frequently, ulcers inside the mouth result in decreased appetite or not eating due to pain and discomfort
- Affects the skin under the front legs and inside area of the back legs
- Painful and itchy
- Anorexia (not eating), depression, and fever
- Commonly have secondary bacterial infections
What breeds are most affected by pemphigus?
Breeds noted to be most affected include domestic short-haired cats, domestic long-haired cats, Siamese, Himalayan, Persian, Maine Coon, American Blue, Somali, Scottish Fold and Ragamuffin.
What tests are used to diagnose pemphigus in cats?
Your vet will perform a thorough physical exam on your cat, including blood tests (feline leukemia/feline immunodeficiency test, blood chemistry panel, and complete blood count), and urinalysis. It’s important to assess your cat’s overall health before beginning immunosuppressive medications which have potentially serious side effects. Provide your vet with a complete and thorough history of your cat’s health, any issues, when you first noticed the signs, any medications, and if your cat spends time outdoors or in direct sunlight.
Your vet will examine your cat’s skin and under anesthesia, take a skin sample or biopsy for evaluation. In addition, cytology (examining a sample under a microscope) of fluid-filled pustules/cysts can help diagnose pemphigus. Secondary skin infections often need to be cultured to determine the most effective antibiotic to be prescribed. The results from these tests will be sent to your vet and discussed with you during a follow-up consultation.
Treatment Options for Cats with Pemphigus
Your vet will discuss the treatment options recommended and tailored to your cat depending on the form of pemphigus diagnosed, the lab test results, as well as your cat’s history and temperament.
Immunosuppressive treatments such as corticosteroids and azathioprine are often prescribed.
For cats not responding to these medications, veterinarians may prescribe Chlorambucil, chrysotherapy (or gold salts), and cyclosporine.
Your vet will discuss what to expect. Follow-up consultations are needed to monitor response to therapy as well as negative side effects that may make it necessary to modify the dosage of medication or change to an alternate therapy.
Prognosis for Cats with Pemphigus
Studies have shown that cats diagnosed with pemphigus require treatment for life. This includes frequent monitoring for recurrence of symptoms, blood tests, and other diagnostics due to the serious potential side effects from the medications needed to treat pemphigus.
Initially, you can expect your cat to have follow-up appointments with your vet about every one to three weeks. Your cat will have routine blood work tests to assess progress and potential negative side effects from the medications. Once your vet has determined that your cat is in remission you can expect to see your vet about once a month to every three months.
Since the sun can make this disease worse it is recommended to limit exposure to sunlight if possible.
A small percentage of cats diagnosed with pemphigus are euthanized due to their disease or from being unable to tolerate the side effects of the medications used to treat the disease.
When to Contact a Vet
If you notice your cat suddenly develops changes in their skin as described above, schedule an appointment with your vet to determine a diagnosis and treatment plan.
Need to speak with a veterinarian regarding your cat’s skin or another condition?
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