(See also Overview of Blistering Disorders.)
Pemphigus vulgaris is a rare, severe autoimmune disease in which blisters of varying sizes break out on the skin and on the lining of the mouth and other mucous membranes.
Pemphigus vulgaris occurs when the immune system mistakenly attacks proteins in the upper layers of the skin.
People have severe blistering in the mouth and on other areas of the body, and sometimes sheets of skin peel off.
Doctors can diagnose pemphigus vulgaris by examining skin samples under a microscope.
Treatment usually involves corticosteroids or drugs that suppress the immune system.
Pemphigus develops most often in middle-aged or older people, affecting equal numbers of men and women. It rarely develops in children.
In this autoimmune disease, the immune system, which normally protects the body against foreign invaders, mistakenly attacks the body’s own cells—in this case, the skin. Antibodies produced by the immune system attack specific proteins that connect the epidermal cells (the cells in the top layer of skin) to each other. When these connections are disrupted, the cells separate from each other and from the lower layers of the skin, and blisters form. Similar-appearing blisters occur with a less dangerous skin disorder, bullous pemphigoid.
The major symptom of pemphigus vulgaris is the development of clear, soft, and painful (sometimes tender) blisters of various sizes. In addition, the top layer of skin may detach from the lower layers in response to slight pinching or rubbing, causing it to peel off in sheets and to leave painful areas of open skin (erosions).
The blisters often first appear in the mouth and soon rupture, forming painful sores (ulcers). More blisters and ulcers may follow until the entire lining of the mouth is affected, causing difficulty swallowing, eating, and drinking. Blisters form in the throat as well. Blisters can form on the skin and rupture, leaving raw, painful, crusted wounds. The person feels generally ill. Blisters may be widespread, and once ruptured, they may become infected. When severe, pemphigus vulgaris is as harmful as a serious burn. Similar to a burn, the damaged skin oozes large amounts of fluid and is prone to infection by many types of bacteria.
Doctors usually recognize pemphigus vulgaris by its characteristic blisters, but the disorder is diagnosed with certainty by examining a sample of skin under a microscope (skin biopsy). Sometimes doctors use special chemical stains that allow antibody deposits to be seen under the microscope. Doctors differentiate pemphigus vulgaris from bullous pemphigoid by noting the layers of skin involved and the particular appearance of antibody deposits.
Without treatment, pemphigus vulgaris is often fatal, usually within 5 years. However, when people are treated with corticosteroids given by mouth (orally) or vein (intravenously), only about 5 to 15% of them die within 5 years. The risk of death and severe complications tends to be higher if people have widespread pemphigus vulgaris, require high doses of corticosteroids or other drugs that suppress the immune system to control the disorder, or have other serious disorders.
People who have moderate to severe disease are hospitalized. In the hospital, the raw skin surfaces require extraordinary care, similar to the care given to people with severe burns. Antibiotics may be needed to treat infections in ruptured blisters. Dressings can protect raw, oozing areas.
High doses of corticosteroids are the mainstay of treatment. They are taken by mouth or, if the person is hospitalized, may be given by vein. If the disease is controlled, the dose of corticosteroids is gradually reduced (tapered).
If the person does not respond to treatment or the disease flares up as the dose is tapered, a drug that suppresses the immune system, such as azathioprine, cyclophosphamide, methotrexate, mycophenolate mofetil, cyclosporine, or rituximab, is also given. Drugs that suppress the immune system may also be given to reduce the need for corticosteroids in people who have needed corticosteroids for a long time or at high doses. People with severe pemphigus vulgaris may also undergo plasma exchange, a process in which antibodies are filtered from the blood (see Controlling Diseases by Purifying the Blood). Immune globulin given by vein is another treatment that can be used for severe pemphigus vulgaris. Some people respond well enough to discontinue drug therapy, whereas others must continue taking low doses of the drugs for long periods.