What Are Autoimmune Blistering Disorders?
Autoimmune blistering disorders (also called autoimmune blistering diseases or autoimmune bullous disorders) are a group of rare skin diseases. They happen when your immune system attacks your skin and mucous membranes -- the lining inside your mouth, nose, and other parts of your body. This causes blisters to form.
Researchers have found many types of this disorder. Although there's no cure for them, your doctor can give you treatments to help heal the blisters and prevent complications.
Types of Autoimmune Blistering Disorders
Autoimmune blistering disorders are broken down into different types. These are some of the main ones:
Pemphigoid is another group. It has three main types:
- Bullous pemphigoid usually affects people between the ages of 60 and 80. It causes itchy blisters to form on the arms, thighs, and belly.
- Mucous membrane pemphigoid affects the lining of the mouth, eyes, nose, throat, and genitals.
- Pemphigoid gestationis affects women during pregnancy or just after their baby is born. It starts as a bumpy rash on the belly, arms, and legs. Then the bumps turn into blisters.
IgA mediated bullous dermatoses are disorders in which the immune system makes a lot of immunoglobulin A (IgA), a type of antibody that fights bacteria, toxins, and viruses. It comes in two types:
- Dermatitis herpetiformis affects people with celiac disease (who are sensitive to the wheat protein called gluten). It causes clusters of itchy blisters to appear on the elbows, knees, scalp, and buttocks.
- Linear IgA disease causes new blisters to form a ring around old ones on the skin. This is sometimes called a “cluster of jewels.” This type affects mucous membranes, too.
Epidermolysis bullosa acquisita mostly affects middle-aged and older adults. It makes the skin so fragile that blisters form from minor injuries.
Autoimmune Blistering Disorder Symptoms
The places on your body where blisters form depends on which disorder you have. Some autoimmune blistering disorders cause blisters to grow on the skin. Other types cause them to form in the mucous membranes that line the mouth, nose, throat, eyes, and genitals.
They can be painful or itchy. They can break open and leave a sore.
Autoimmune Blistering Disorder Causes
When your immune system is working as it should, it attacks bacteria and other invaders before they can make you sick. In autoimmune blistering disorders, your system mistakes healthy cells in your skin and mucous membranes for unwanted intruders.
Your immune system makes proteins called antibodies. These attack the substances that hold the outer (epidermis) and inner (dermis) layers of skin together. The damage causes the two layers of skin to separate. Fluid collects between the two and forms blisters.
Doctors don't know what causes the immune system to misfire. Some people have genes that make them more likely to get one of these disorders. Then, something actually triggers it, such as:
- Ultraviolet light from the sun
- Chemicals used to kill pests
Some medicines can also cause autoimmune blistering disorders. These include:
- Diuretics and other medicines for high blood pressure
- Rheumatoid arthritis medications
- Antipsychotic medicines
- Antibiotics such as amoxicillin (Moxatag), ciprofloxacin (Cetraxal, Ciloxan, Cipro), and penicillin
Usually, the blisters go away once you stop taking the medicine causing them.
Autoimmune Blistering Disorder Complications
Blisters can cause long-term problems if they form in certain parts of the body or break open.
- Blisters that pop open can cause infections.
- After they heal, they can leave scars.
- In the throat or lungs, they can make it hard to eat, swallow, or breathe.
- In the mouth, they can cause gum disease and tooth loss.
- In the eyes, they can affect sight.
Autoimmune Blistering Disorder Diagnosis
You'll see a dermatologist. They will look at your skin and see where the blisters have formed.
You might get one or more of these tests:
- Blister biopsy. Your doctor removes a piece of the blister and looks at it under a microscope. A biopsy can show where the skin layers have separated.
- Direct immunofluorescence. A chemical is placed on the skin biopsy sample. Then it is tested for antibodies. The type of antibodies in your skin can show which type of blistering disorder you have.
- Blood test. Your doctor tests a sample of your blood for antibodies. This test can show how severe your condition is. It can also help the doctor see whether treatment is working.
Sometimes it’s hard to tell the difference between autoimmune blistering disorders and other conditions, including:
- Genetic blistering disease, a group of disorders caused by changes in a gene needed for healthy skin
- Grover’s disease, a rare skin disorder that can cause small red lesions and blisters
- Other skin conditions that cause blisters, such as erythema multiforme or impetigo
Autoimmune Blistering Disorder Treatment
Your doctor will decide on a treatment based on your symptoms. Medicines for these disorders lower the immune system response and prevent it from attacking your skin and mucous membranes. Treatments might include prescriptions from these classes of drugs:
- Corticosteroids, such as prednisone (Deltasone, Prednicot, Rayos), that also ease inflammation
- Immunosuppressive medicines, such as azathioprine (Azasan, Imuran), cyclophosphamide, or mycophenolate mofetil (CellCept)
- Biologic drugs, such as rituximab (Rituxan), also used in some cancer treatments
For more serious cases, your treatments might include:
- Intravenous immunoglobulin G (IVIG). This is a blood product you get through a needle into a vein. IVIG is an antibody found in plasma -- the liquid part of blood. It's taken from thousands of donors and pooled together. IVIG treatment gives you healthy antibodies to take over for the unhealthy ones that caused your disorder.
- Plasmapheresis. This treatment removes the harmful antibodies from your blood. The part of blood that's removed is replaced with blood from a donor that contains healthy antibodies.
Blisters that pop open can get infected. These drugs help prevent an infection:
- Antiviral drugs
- Antifungal drugs
Autoimmune Blistering Disorder Home Care
To prevent infections and help you stay more comfortable, take care of your blisters. Keep them clean the way your doctor recommends. Try not to pop them. This can leave scars. If a blister is in an uncomfortable place such as your foot, your doctor can release the fluid with a clean needle. Also:
- Wash your sheets, towels, and clothes often. Make sure everything that touches your skin is clean.
- Care for your teeth. If you have blisters in your mouth, ask your dentist how to brush your teeth and gums without causing pain and more damage.
Each person with autoimmune blistering disorders is different. Some people have only mild blisters that go away on their own. Others have more severe skin problems that are harder to treat. Talk to your doctor about your situation. Try different treatments until you find one that works for you.