Gettysburg Medical News
The Clinical View
by P.E. Hoffsten, MD
9 August 2006

WHAT IS PEMPHIGUS? 

            A lady recently came to the clinic complaining that she had skin problems.  She related that she had intermittent itching on her back or her abdomen.  The problem had been going on for more than a month and she had learned that if she scratched the areas that were itching, she would develop a blister.  She came to the clinic now because she had spontaneously developed a blister remarking that she didn’t even scratch the area that itched and the blister formed anyway.

            On examination of her abdomen, she had a blister the size of half an egg.  It had not broken as she was very careful to protect it.  She knew that several blisters had broken and had taken a long time to heal.  She was wondering what the problem was and what she could do to prevent it.

            She indicated that she was not sick otherwise and had had no other complaints.  On examining her abdomen, the size of the blister was very impressive as I indicted and it was easy to tell her that she had a condition called bullous pemphigoid.  “Bullous” means forming a big blister.  “Pemphigoid” means that the disease looks like a condition called pemphigus.  Whenever a doctor puts the ending “-oid” on the end of a word, he indicates that it means the condition seems to look like the first part of the word but really isn’t that.  Thus, pemphigoid is a condition that looks like pemphigus but isn’t.  The lady had done some reading before she came to see me and she was aware of these words and wanted to know what they meant.  I explained to her as above.  Pemphigus (technically pemphigus vulgaris) is a disease with hereditary permission to form an allergy to the cells that make up the skin.  These cells are called keratinocytes.  These are the cells that lie on the surface of a basement membrane in the skin.  These cells initially are big and succulent like other cells but then they slowly dehydrate and turn into the surface of your skin which is dry, sometimes flakey like dandruff.  Everyday a few of these cells flake off all over your body and everyday a few more are formed flattening out making the skin surface.  The skin surface is critically important in protecting a person from the great outside world and all the bacteria that are in it.

            Unfortunately, some few people develop and allergy to these keratinocytes in their own skin.  As I mentioned above, there are hereditary genes that will allow this to occur although it does not occur in everybody that has these genes.  When the condition occurs, it can be fatal.  It is treated with large doses of cortisone and other medications designed to prevent organ rejection.  The medications that help a kidney transplant patient keep their transplanted kidney or a heart transplant patient keep their transplanted heart can be used to decrease the severity of pemphigus.  The condition tends to wax and wane lasting years requiring attention all of the time.

            I explained to the patient that she did not have pemphigus but instead she had a condition called bullous pemphigoid.  In this condition, the person had become allergic to the basement membrane upon which the keratinocytes normally reside.  And again, very large blisters can form.  Different than pemphigus vulgaris, this condition is much easier to control although it does require cortisone treatments as does pemphigus.

            The patient had read that 25% of the people that have bullous pemphigoid have an underlying malignancy associated with it.  We went through an extensive evaluation of this lady looking to see if there might be a cancer of the colon or the stomach or the breast.  Very fortunately, she was in the 75% of the people that do not have a malignancy to explain their bullous pemphigoid.  She got started on a relatively small dose of cortisone which resolved her itching completely.  She is now on a maintenance dose of cortisone at very low doses and is doing very well with this.  At some point, we could consider stopping the cortisone or using alternative medications but we have not gotten that far to this point.

            Obviously, the most common cause of blister in our society is a burn.  When a person’s skin gets too hot or gets too much sunshine the keratinocytes can be killed.  Granted they will grow back relatively quickly in a minor second degree burn.  In a third degree burn, the basement membrane is also damaged and deep tissue damage occurs.  Third degree burns take a long time to heal and often require skin grafting.

            There is one other condition called dermatitis herpetiformis.  In this condition, the person forms multiple small blisters almost like heat rash.  These patients have a very special type of allergy not only to their skin but to their kidneys and very frequently to wheat germ.  The allergy to wheat germ is called celiac disease and is associated with severe diarrhea and malnutrition.  Fortunately, the condition can also be treated with small doses of steroids although the allergy to wheat requires the person to completely rid their diet of wheat products.  This is a very difficult feat to accomplish.  Wheat is everywhere in our diet including salad dressings, breads, gravy, even chocolate.  Very special attention to the diet to rid it completely of wheat is necessary.

            The healthcare providers at your local clinics are aware of these considerations.  Often times, the condition can be diagnosed by the itching even prior to the development of a blister.  This can prevent a great deal of grief from developing later on.