Pemphigus foliaceus, pemphigus vulgaris, pemphigus erythematosus and pemphigus vegetans There are several related immune mediated skin disorders called pemphigus complex. These have a common mechanism of action in which the body produces antibodies against the outer layer of the skin (the epidermis). Pemphigus foliaceus is the most common of these diseases in the dog. It is seen more often in Akitas, chow chows, dachsund, bearded collies, Doberman pinscher, schipperke, Finnish spitz and Newfoundland dogs. Pemphigus erythematosus is second most common and may just be a milder form of pemphigus foliaceus. It is seen more commonly in collies, Shetland sheepdogs and German shepherds. Cats are also susceptible to phemphigus disorders. These diseases look exactly alike except that pemphigus erythematosus usually only affects the head and feet. The more common forms of pemphigus produce scaling skin, scabbiness and sometimes pustules (pus filled sores that look like pimples). Early in pemphigus foliaceus the disease may be confined to the head and feet, making it hard to distinquish from pemphigus erythematosus. Later it spreads to more of the body. Careful examination of the skin may reveal the presence of blisters, which are very indicative of these diseases. The blisters rupture quickly and may not be seen. If the sores become infected it is possible for severe illness to develop but this is not a common complication. Pemphigus vulgaris is the most severe form of the disease. In this disorder, there is severe ulceration of the skin, usually where "normal" skin meets "specialized" skin --- around the mouth, anus, prepuce, nose and vagina. The mouth is almost always affected. Secondary complications are more common with pemphigus vulgaris than other forms of pemphigus and can be very severe. Pemphigus vegetans may be a less severe form of pemphigus vulgaris but it does look different. In this form of pemphigus there are warty growths that may ulcerate. There are a lot of diseases that can look like pemphigus disorders. Drug eruptions (skin reaction to administered medications) are probably the most common "look alike" disorder but systemic lupus erythematosus, discoid lupus and skin cancers are other fairly common diseases that may be confused with pemphigus. Diagnosis of pemphigus is best done by skin biopsy. Sometimes specialized testing must be done on the biopsy samples -- which often means doing them again. Treatment of pemphigus vulgaris and pemphigus foliaceus can be pretty frustrating. Usually it is necessary to use prednisone (a corticosteroid) for the life of the dog to control the symptoms of skin scabs and scaling for pemphigus foliaceous and ulceration of skin around mucous membranes (the more "specialized" skin). Prednisone often will not work alone, though. It is usually necessary to use a second immune suppressive medication like azathioprine or chemotherapeutic agents to get complete control of the disease. Treatment of pemphigus erythematosus and pemphigus vegetans may not be necessary or is usually possible with topical corticosteroids or low to medium dosages of prednisone. Due to the serious immunosuppressive tendencies of the medications used to treat pemphigus diseases it is usually necessary to closely monitor the health of pets under treatment. To succeed in keeping a dog comfortable when affected by the more severe pemphigus diseases takes close cooperation between the client and veterinarian. Teamwork is important in treating pemphigus.

Mike Richards, DVM

Pemphigus - Cysts on feet in Weimaraner

Question: Hello. My name is Stacy and I have a question regarding my dog, who is a 2-year-old purebreed Weimaraner. My vet recently took biopsies of cysts/pustules that have been resistant to antibiotics and that appear on all of four of her paws (underneath her pads). My vet believes that she may have Pemfigus. Can you please provide me with any information you may have on this disease? What is the chance that my dog will live out a normal life span with this disease (and its treatment, which I am told is Prednizone). Thank you so much for your time. --Stacy

Answer: Stacy-

Before moving on to phemphigus, I do have one suggestion. I recently read, or heard, somewhere, but unfortunately can not remember where, that metronidazole (Flagyl Rx), worked really well for cysts on the feet that did not seem to be responding to other antibiotics. I would not normally have thought of this antibiotic for this use, but we have tried it twice recently and once it worked well and once it didn't work at all. Still, considering the difficulty that we have getting these cysts to go away, if this works even some of the time it is worth remembering.

Pemphigus complex is the usual name applied to a group of immune mediated (autoimmune) diseases affecting the skin. There are four forms of pemphigus which have been recognized in dogs and cats, pemphigus foliaceus, pemphigus erythematosus, pemphigus vulgaris and pemphigus vegetans. These are related disorders, with two main groups. Pemphigus foliaceus and pemphigus erythematosus being variants of one group and pemphigus vulgaris and vegetans being variants of the other group.

Pemphigus foliaceus is the most common form of pemphigus in dogs and cats. It is characterized by bumps on the skin (macules) that become pustules and then dry scabs on the skin. It is most commonly found on the face and feet, but lesions can occur on other areas of the body. In dogs the toenails are usually normal but in cats they may damaged by the disease. Some pets are itchy when they have pemphigus lesions but not all are affected in this way. Dobermans, schipperkes, akitas, chows, bearded collies, rottweilers and Siamese cats are usually included in lists of breeds most likely to be affected by this condition.

Pemphigus erythematosus is much less common and seems to affect collies more than other breeds. Lesions are similar but usually stay on the face and may cause loss of color (depigmentation) of nose.

Pemphigus vulgaris usually causes blisters to form, which become skin ulcers when they burst. The blister stage can be really short term, so careful observation for the blisters is important. This form of pemphigus really likes the areas where normal skin meets soft specialized skin, such as the edges of the lips, eyelids and rectum. When the feet are affected it is much more likely for the toe nails to be shed when pemphigus vulgaris is present. Since oral ulcers are common in pemphigus vulgaris but less common with pemphigus foliaceus, this finding can help to differentiate between the conditions. There may or may not be itching and some pets seem to have pain associated with pemphigus vulgaris.

Pemphigus vegetans is a very rare form of pemphigus, in which warty sores appear and are usually distributed over much of the body.

It is necessary in most cases to have a skin biopsy done, then to have it examined by a pathologist who is experienced at looking at skin lesions (dermatopathologist) to confirm the diagnosis of pemphigus complex. This disease can look like systemic lupus erythematosus, but an ANA (anti-nuclear antibody) test is usually negative when pemphigus foliaceus, vulgaris or vegetans is present and positive when pemphigus erythematosus is present. Negative ANA tests also occur with discoid lupus, another disease that is sometimes confused with pemphigus based on the appearance of the problem.

Treatment for all of the conditions is similar, involving immunosuppressive doses of corticosteroids, usually prednisone, often combined with other immunosuppressive medications, such as azathioprine (Imuran Rx) or chlorambucil ( Leukeran Rx). Since treatment is usually necessary for life, it is really important to be certain of the diagnosis before committing to lifelong therapy, whenever possible.

Another similar disease is bullous pemphigus, which affects primarily collies, shelties and dobermans. This disorder affects a different layer of the skin but otherwise looks a lot like pemphigus vulgaris. Treatment is the same.

Hope this helps.

Mike Richards, DVM 9/19/2000

Pemphigus treatment in Labrador Retriever

Q: Dr. Richards, My 5 year old Labrador Retriever was diagnosed with Pemphigus Foliaceus 17 months ago. The prescribed drug therapy of Prednesalone and leukeran was successful in keeping him comfortable until about 2 months ago. Since then, his condition has deteriorated. Our vet is a general practioner and this is the only treatment he has suggested based on his limited knowledge of the treatments. Do you have any suggestions as to alternate medications that can be used? Max weights approximately 120 now, his pre-steroid weight was 80 pounds. Thank you for your time and consideration. I look forward to hearing from you. Angelina

A: Angelina-I am a general practitioner, too -- so my actual "hands on" experience with phemphigus is limited to a handful of cases. There are veterinary dermatologists and they often can help in management of difficult problems such as phemphigus if standard therapies aren't working.

Corticosteroids such as prednisone are the mainstay of phemphigus therapy. These medications are usually effective. When they are not, there are some alternatives, including azathioprine (Immuran Rx), gold salts, and a combination of niacinamide and tetracycline. There are also occasional reports of dogs with pemphigus responding to single antigen food trials (food elimination diets) but I am not aware of a scientific study addressing this.

Mike Richards, DVM

Pemphigus in Saluki

Q: Dear Dr. Mike, My 12 year-old Saluki dog has been diagnosed with Pemphigus (auto-immune related) and is on 40 mg prednisone per day. I've tried to reduce this dose to 20 mg per day with the result that the skin around his nostrils and on the scrotum gets worse (little blisters and bumps). I've been told that steroids cause the weakening of the bone and as Kashmir still wears a steel plate due to a bone fracture some years ago, I would like to know what I can do to counteract this procedure. Also, I think that administering cortisone does not get to the root of the problem, but do I have another choice?

A: There are several types of pemphigus and they vary somewhat in their response to treatment. If your dog has pemphigus vulgaris, it is probably unlikely that you will be able to reduce the dosage of prednisone and maintain control of the pemphigus. There is a better chance with the other forms of pemphigus but since you have tried unsuccessfully to reduce the dose it may not be possible in your dog's case. You might try other immunosuppressive medications, such as azathioprine (Immuran Rx) or gold salt therapy (Auranofin or Solganol Rx) but these are probably more likely to cause side effects. Some veterinarians have reported success in treating autoimmune diseases in dogs with other medications but I have not personal experience with anything but corticosteroids and azathioprine. So far, these have usually worked for us. A combination of tetracycline and niacinamide has also been advocated for use in pemphigus conditions. I do not know the mechanism of action of this combination. The reported success rate in the article I saw (Journal of the American Veterinary Medical Association, May 15, 1992, White et al.), had fairly low success rates for this combination but it worked for some dogs. Since it has a lower likelihood of secondary side effects than most of the other treatments it may be worth considering.

I disagree somewhat with your statement that administering cortisones did not address the root of the problem. In this particular case, the problem is the immune system and cortisones directly suppress it. I think that is an approach that is directed at the problem. Its just that cortisones affect so many other body systems that it isn't the ideal approach.

Corticosteroids can enhance bone resorption, enhance calcium excretion by the body and inhibit vitamin D activation. All of these effects can weaken bone. I do not think that this causes clinically observable symptoms in many dogs but yours may be at increased risk of problems from this due to the old injury. I think the major problem with bone from the use of corticosteroids is that it inhibits fibrocartilage repair in the joints and that this can lead to an increased rate of degeneration in dogs with degenerative joint disease. This effect may or may not be important in your Saluki, depending on the existing joint problems.

It might be worth trying the niacinamide/tetracycline combination to avoid long term use of corticosteroids. If that doesn't work, I think that prednisone is probably the best choice for long term use since it is actually the least likely to cause side effect of the remaining medications used in this condition.

I'm sure your veterinarian will be willing to work with you to keep the dosage as low as possible while still controlling the symptoms.

Mike Richards, DVM


Michael Richards, D.V.M. co-owns a small animal general veterinary practice in rural tidewater Virginia. Dr. Richards graduated from Iowa State University's College of Veterinary Medicine in 1979, and has been in private practice ever since. Dr. Richards has been the director of the PetCare Forum...