Pemphigus

Understanding Pemphigus

Pemphigus is a group of rare autoimmune skin conditions that cause large fluid filled blisters to form. An autoimmune disorder develops when the immune system malfunctions and creates antibodies that attack and cause damage to a part of the body. In pemphigus, molecules called desmogleins are attacked. Desmogleins function as the glue of the epidermis (outer layer of the skin). When the desmogleins are destroyed epidermal cells become separated. This is called ancantholysis and results in blisters that form on the skin and mucous membranes (mucus-secreting tissue such as those lining the mouth and nose). Pemphigus can occur in any race and gender. Onset is most common in middle or older adults but two types, pemphigus vulgaris and pemphigus foliaceous, occur in young adults and children. Certain ethnic groups are more prone to developing pemphigus vulgaris, including people of eastern European Jewish and Mediterranean descent. Pemphigus is similar to pemphigoid, another group of rare autoimmune blistering disorders. The blisters in pemphigus are more superficial and fragile than those in pemphigoid.

Symptoms of Pemphigus

Symptoms of pemphigus, including location and nature of blisters, and treatments depend on the type of pemphigus. There are several types:

• Vulgaris: Most common type. Blisters may form in the mouth first and then spread to the skin and even genitals. Blisters are frequently painful but not itchy. Blisters in the mouth make chewing and swallowing difficult.
• Foliaceus: Least severe type. Blisters may form on the scalp and face first and then spread to the chest and back. Blisters are not usually painful and are thicker and form crusts.
• Paraneoplastic: Associated with certain forms of cancer. Blisters form inside the mouth and may affect the esophagus, making swallowing difficult.

Diagnosis of Pemphigus

Diagnosing pemphigus can be very difficult and may take months or even years. When the disease is diagnosed early, before it is widespread and severe, it is easier to control and results in fewer complications. Unfortunately, early diagnosis is not typical. A person with pemphigus may present with a single blister that does not heal. They may see several physicians and take several medications that do not work before they get a definitive diagnosis and the right treatments to control the disease so blisters heal, and new ones do not form.

Diagnostic testing may include:

• Your doctor may rub an area near a blister. In pemphigus, it is likely the top layers of skin will be rubbed off when this is done. This is called Nikolsky's sign.
• Skin biopsy with immunofluorescence. The tissue is stained with a dye and is examined under a special microscope to look for the presence of autoantibodies.
• Blood work to test for autoantibodies that occur with pemphigus.

Treatment of Pemphigus

Treatment of pemphigus may include steroids, immunosuppressants, immune globulin therapy and/or rituximab (e.g., Rituxan^®). Immune globulin therapy is administered into the blood stream intravenously (IVIG). Steroids are typically initiated in high doses to get the disease under control and then are weaned. If during the weaning process blisters reappear and/or worsen, immunosuppressants are started and weaning is reattempted. If this is unsuccessful in controlling the blisters, IVIG and/or rituximab may be added to the treatment plan. In very severe cases, IVIG may be the first treatment prescribed.

Resources:

• The International Pemphigus and Pemphigoid Foundation
  www.pemphigus.org
• Information from the National Institutes of Health:
  Questions and Answers about Pemphigus, Pemphigus information

References:

• Pemphigus Vulgaris | Johns Hopkins Medicine