Overview of Pemphigus Foliaceus
Pemphigus foliaceus is a severe skin disease that is characterized by pustules and blisters that rupture, causing damage to the skin of the face, ears, feet and eventually the entire skin.
This disease results when the animal recognizes a specific component of his own skin (desmoglein I) as foreign and makes antibodies against that component. Desmoglein I is important in attaching skin cells to each other. Lack of this component causes the outer layer of the skin to split apart and fill with fluid and cells leading to a blister or pustule. This abnormality of the immune system is an example of an autoimmune disorder.
Middle aged to older cats are more prone to this disease. This disease has a severe health impact on the animal and can be fatal if not treated aggressively.
What to Watch For
Diagnosis of Pemphigus Foliaceus in Cats
Your veterinarian may puncture an intact pustule and collect the contents to put on a microscope slide for cytology (microscopic exam of the cells). This test may lead to a preliminary diagnosis that must be confirmed by biopsy. This test also helps to rule out other pustular skin diseases like pyoderma.
Treatment of Pemphigus Foliaceus in Cats
Once the disease is successfully in remission, other immunosuppressive drugs like azathioprine in cats may be used to help lower the dose of corticosteroids needed.
Home Care and Prevention
Give all medications as directed. Follow up appointments with your veterinarian are critical to allow for adjustment of drug dosages to maximize efficacy and minimize side effects.
There is no known way to prevent the development of this disease.
In-depth Information on Pemphigus Foliaceus in Cats
Pemphigus foliaceus is an autoimmune disease. In other words, it is caused by the animal’s own immune system. In this case, the body recognizes a glycoprotein, desmoglein I, found in the skin as foreign and mounts an antibody response against it. This glycoprotein is involved in the attachment of one skin cell to another within the outer layer of the skin (epidermis).
The result of the antibody binding to desmoglein I is a loss of attachment leading to a cleft within the epidermis. This cleft fills with fluid and white blood cells called neutrophils, which is the pustule that we see. Cells that are losing their ability to attach to one another round up and float into the middle of the fluid. These large, round cells are called acanthocytes. The pustules are very fragile and rupture easily leaving a lesion in the epidermis that is covered by a crust.
This disease tends to begin on the bridge of the nose and the ears and progress to the feet, including the footpads, and legs. Eventually the skin of the trunk and the rest of the body are affected. Often the lesions will cross from the skin on the bridge of the nose to the nose itself causing a loss of the normal cobblestone appearance and loss of pigmentation. Skin lesions that involve the nose are seen almost exclusively with autoimmune skin diseases. Animals with pemphigus foliaceus may have a fever and refuse to eat.
Other diseases that may be confused with pemphigus foliaceus are those that also have pustules as their major lesion. These include: