Autoimmune Blistering Diseases

What are autoimmune blistering diseases?

Autoimmune blistering diseases, also known as autoimmune bullous disorders, are a set of rare skin disorders where the patient experiences severe blistering. Autoimmune blistering disease occurs when our body’s immune system begins to attack epithelial tissue on the skin instead of invaders that pose a risk to our health.

In this condition, the body’s immune system mistakenly attacks proteins that act as the “glue” to keep the epidermis (the outermost layer of your skin) attached to the underlying dermis tissues. When this occurs, the adhesion of the epidermis to the underlying dermis tissue becomes weaker, resulting in a separation of skin layers, ultimately causing blisters and itching to occur. 

Are they rare?

Autoimmune blistering diseases are very rare. Pemphigus, a type of autoimmune blistering disease, is estimated to occur in 0.75-5 people per 1 million. ^[1]

What are the characteristics?

Sores and blisters tend to develop on the skin and/or mucous membranes (e.g. mouth, throat, genitals). These can break open, resulting in open wounds and sores which may ooze and become infected. ^[2]

What are the causes and symptoms?

Autoimmune blistering disease occurs when our body’s immune system (our body’s defense against infections) begins to attack our own skin instead of attacking germs. The reason for this is still unknown, however, research shows that there may be a link between the use of certain medications and skin damage (e.g. sunburn). ^[3] There is also a higher likelihood of developing autoimmune blistering disease in those assigned female at birth, as well as having a worse overall impact on their quality of life compared to those assigned male at birth. ^[4]

Common symptoms of autoimmune blistering disease include: 

• Blisters/lesions on the skin and/or mucous membranes
• Itching, pain or sores at the site of blistering 

What complications can occur?

Sites of blistering and erosions of the skin can become infected, and in extreme cases may spread to your bloodstream, causing sepsis. Painful mouth sores can make eating difficult, thus creating an environment where malnutrition can develop.  Particular subtypes of autoimmune blistering disease can result in death if left untreated.^[2] Medications used as treatment can have various side effects, including high blood pressure and infections.

What are the different types of autoimmune blistering diseases?

There are several types of autoimmune blistering diseases, including pemphigus, pemphigoid, epidermolysis bullosa acquisita, and IgA-mediated dermatoses, which are described below:

Pemphigus

• Pemphigus is an uncommon group of autoimmune blistering diseases with a high number of cases in women. Subtypes of pemphigus include: pemphigus vulgaris, which accounts for approximately 70% of all pemphigus cases, and pemphigus foliaceus, which accounts for about 15–20% of all pemphigus cases. More uncommon examples include: paraneoplastic pemphigus, drug-induced pemphigus, pemphigus herpetiformis, and pemphigus erythematosus. It mainly affects patients aged 20-40 years and commonly results in blisters and sores on the skin and mucous membranes (e.g. mouth and gums). ^[4] 

Pemphigoid 

• The main types of pemphigoid include bullous pemphigoid, mucous membrane pemphigoid, and pemphigoid gestationis. The conditions are characterised by blistering and skin erosions/eruptions. The bullous pemphigoid subtype mainly impacts people over the age of 60 beginning with symptoms of itchy rashes appearing as red/pink patches on white skin and dark reddish brown on dark skin. The condition then develops into large blistering on the skin. ^[3] Mucous membrane pemphigoid is characterised by blistering that mainly affects the mouth and mucous membranes of the body, and pemphigoid gestationis most commonly occurs in women during pregnancy or during the postpartum period (shortly after birth). 

Epidermolysis bullosa acquisita

• This is a rare form of autoimmune blistering disease that typically affects middle-aged and older individuals. Epidermolysis bullosa acquisita rarely impacts the mucous membranes and mainly affects the skin (most commonly the elbows, knees, pelvis, buttocks, and/or scalp). However, a fraction of epidermolysis bullosa acquisita patients have an inflammatory form of the disease which can often affect the mucous membranes as well as the skin. 

IgA-mediated dermatoses

• This type of autoimmune blistering disorder is distinguished by elevated levels of a particular type of protein in the body known as immunoglobulin A (IgA). In IgA-mediated dermatosis, IgA tends to build up in the skin, resulting in itchiness and blisters. Subtypes of IgA-mediated dermatoses include dermatitis herpetiformis (also known as Duhring disease) and linear IgA disease. 

Diagnosing autoimmune blistering diseases

Blistering on the skin and mucous membranes can occur due to a number of different conditions, many of which are more common than autoimmune blistering disease. Because pemphigus is rare, it can be more difficult to diagnose; your doctor may wish to refer to a skin specialist (dermatologist). 

If you visit the doctor, they may examine your skin and mouth for redness and blistering. Additionally, they may run a number of tests, including: 

• Blood tests: To measure the levels of a specific antibody production in the blood.
• Skin biopsy: To detect the presence of pemphigus-associated antibodies in your blood. 
• Endoscopy: To check for sores in your throat, using a procedure where an endoscope (flexible tube) is inserted down your throat. 

Treating autoimmune blistering diseases

Many types of autoimmune blistering diseases go away on their own, though it can last for some years. There are treatments available that can help your skin heal more quickly, reduce the likelihood of skin infections, and prevent the development of more patches and blistering . The most common treatments include: steroid tablets, steroid creams, and antibiotics. 

Preventing autoimmune blistering diseases

Treatments such as steroid tablets, steroid creams, and antibiotics can prevent the disease from getting worse, by reducing the spread and severity of blistering. 

FAQS

• What autoimmune diseases cause blisters?

There are many different forms of autoimmune diseases that cause blisters (known as autoimmune blistering diseases). These include: pemphigus, pemphigoid, IgA-mediated dermatoses and epidermolysis bullosa acquisita. 

• What autoimmune disease causes blisters on feet?

Palmoplantar pustulosis is an autoimmune disease that can result in fluid-filled pustules/blisters on the hands and/or feet. ^[5] 

• Which autoimmune disease affects the skin?

Many autoimmune diseases affect the skin, including Behcet’s Disease, Dermatitis Herpetiformis, and Lichen Planus. A longer list and more information on autoimmune disorders that affect the skin can be found here.