Epidermolysis bullosa is a group of skin conditions whose hallmark is blistering in response to minor injury, heat, or friction from rubbing or scratching. There are three main types of epidermolysis bullosa, with numerous subtypes. Most are inherited.

Most types of epidermolysis bullosa initially affect infants and young children, although some people with mild forms of the condition don't develop signs and symptoms until adolescence or early adulthood. Some infants are born with blisters. Mild forms of epidermolysis bullosa may improve with age, but severe forms may cause serious complications and can be fatal.

There's no cure for epidermolysis bullosa. Treatment depends on the severity, but often is aimed at preventing pain, infection and other complications.

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Epidermolysis bullosa simplex

The primary indication of epidermolysis bullosa is the eruption of fluid-filled blisters (bullae) on the skin, most commonly on the hands and feet in response to friction. Blisters of epidermolysis bullosa typically develop in various areas, depending on the type. In mild cases, blisters heal without scarring.

Depending on the type of the condition, blistering may be present at birth, appear during infancy or occur during adolescence or early adulthood. The three main types are:

• Epidermolysis bullosa simplex, which usually begins at birth or in early infancy
• Junctional epidermolysis bullosa, which generally begins at birth and is usually severe
• Dystrophic epidermolysis bullosa, which generally begins at birth or in early childhood

Epidermolysis bullosa simplex is the most common and least severe type, with the most common and mildest subtype being Weber-Cockayne type, which typically involves blistering of the palms and soles.

Signs and symptoms of epidermolysis bullosa may include:

• Blistering of your skin — how widespread and severe depends on the type
• Deformity or loss of fingernails and toenails
• Internal blistering, including on the throat, esophagus, upper airway, stomach, intestines and urinary tract
• Skin thickening on palms and soles of the feet (hyperkeratosis)
• Scalp blistering, scarring and hair loss (scarring alopecia)
• Thin-appearing skin (atrophic scarring)
• Tiny white skin bumps or pimples (milia)
• Dental abnormalities, such as tooth decay from poorly formed tooth enamel
• Excessive sweating
• Difficulty swallowing (dysphagia)

Other types
Researchers have proposed a fourth type — hemidesmosomal epidermolysis bullosa — one form of which is associated with muscular dystrophy, an inherited disease that involves progressive weakening of muscles.

In another rare type — epidermolysis bullosa acquisita, which isn't inherited — the blistering occurs as the result of the immune system mistakenly attacking healthy tissue. It's similar to a condition called bullous pemphigoid, which also may be related to an immune system disorder. This form of the condition has been associated with Crohn's disease, an inflammatory bowel disease.

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Basement membrane zone

Your skin comprises an outer layer (epidermis) and an underlying layer (dermis). The area where the layers meet is called the basement membrane zone. Where blisters develop depends on the type of epidermolysis bullosa.

In most cases, epidermolysis bullosa is inherited. Researchers have identified more than 10 genes involved with skin formation that, if defective, may cause a type of epidermolysis bullosa. It's also possible to develop epidermolysis bullosa as a result of a random mutation in a gene that occurred during the formation of an egg or sperm cell.

Epidermolysis bullosa simplex
In epidermolysis bullosa simplex, the most common and generally mildest form, the faulty genes are those involved in the production of keratin, a fibrous protein in the top layer of skin. The condition causes the skin to split in the epidermis, which produces blisters.

If you have epidermolysis bullosa simplex, it's likely you inherited a single copy of the defective gene from one of your parents (autosomal dominant inheritance pattern). If one parent has the single faulty gene, there's a 50 percent chance their offspring will have the defect.

Junctional epidermolysis bullosa
In this usually severe type of the disorder, the faulty genes are involved in the formation of thread-like fibers (hemidesmosomes) that attach your epidermis to your basement membrane. This gene defect causes tissue separation and blistering in your basement membrane zone.

Junctional epidermolysis bullosa is the result of both parents carrying and passing on the defective gene (autosomal recessive inheritance pattern), although neither parent may have the disorder (silent mutation). If both parents have the faulty gene, there's a 25 percent chance their offspring will have the defect and develop the disorder.

Dystrophic epidermolysis bullosa
In this type, whose subtypes range from mild to severe, the faulty genes are involved in the production of a type of collagen, a protein in the fibers that attach your epidermis to your dermis. As a result, the fibers are either missing or nonfunctional.

Dystophic epidermolysis bullosa can be either dominant or recessive.

Having a family history of epidermolysis bullosa is the major risk factor for developing the disorder.

Contact your doctor promptly if your child is born with or develops blisters, particularly if there's no apparent reason for them. Blisters can lead to infection and deformity. Your doctor can show you how to care for them properly and advise you on ways to prevent them.

For adolescents and adults, see a doctor if blisters suddenly develop for no apparent reason or if you experience problems swallowing or breathing.

Your doctor may suspect epidermolysis bullosa from the appearance of the skin, but laboratory tests are needed to confirm the diagnosis. They include:

• Skin biopsy. Removing a small sample of affected skin and examining it under a microscope, such as a high-powered electron microscope, can reveal which layer of skin is separating and which type of epidermolysis bullosa is present.
• Genetic testing. Because most forms of epidermolysis bullosa are inherited, the results of genetic testing, usually done with a blood sample sent to a lab for analysis, can confirm the diagnosis.

In its more severe forms, epidermolysis bullosa can have serious complications and can be fatal. Possible complications include:

• Secondary skin infection. Blistering can leave skin vulnerable to bacterial infection, particularly staph infection, and increase your chances for sepsis.
• Sepsis. Sepsis occurs when bacteria from a massive infection enter your bloodstream and spread throughout your body. Sepsis is a rapidly progressing, life-threatening condition that can cause shock and organ failure.
• Deformities. Severe forms of epidermolysis bullosa can cause fusion of fingers or toes and abnormal bending of joints (contractures), such as fingers, knees and elbows.
• Malnutrition. If you or your child has a form of epidermolysis bullosa that causes blistering of the mouth and other mucous membranes, eating may be difficult. The resulting malnutrition can inhibit normal growth.
• Anemia. Continuous loss of blood from open sores and possibly inability to take in adequate nutrition may contribute to iron deficiency anemia.
• Eye disorders. Inflammation in the mucous membrane (conjunctiva) that lines your eyelids and part of your eyeballs can lead to erosion of the transparent, dome-shaped surface of your eyes (cornea) and, sometimes, blindness.
• Skin cancer. As adolescents and adults, people with certain types of epidermolysis bullosa are at high risk of developing a type of skin cancer known as squamous cell carcinoma.
• Death. Infants who have a lethal form of junctional epidermolysis bullosa are at high risk of infections and loss of body fluids from widespread blistering. Their survival also may be threatened because of blistering of internal organs, which may hamper their ability to get enough nourishment and, sometimes, to breathe. Many of these infants die in childhood. Milder forms of epidermolysis bullosa, however, may not affect life expectancy.

Treatment of epidermolysis bullosa aims mainly at preventing complications and easing discomfort from blistering.

Skin care
Blisters may be large and, once broken, susceptible to infection and fluid loss. Your doctor may instruct you in puncturing blisters with a sterile needle. Leaving the roof of the blister intact allows for drainage of the blister while protecting the underlying skin. Your doctor may recommend applying an antibiotic ointment or petroleum jelly or other moisturizing substance before applying a nonsticking bandage.

For wounds that don't heal over time, your doctor may recommend skin grafts, using either your own skin or your child's own skin from an unaffected area or manufactured skin. Covering the wound with skin can help spur healing.

Surgery
Repeated blistering and scarring can cause deformities, such as fusing of the fingers or toes or abnormal bends in the joints (contractures). Your doctor may recommend surgery to correct these deformities, particularly if they interfere with normal motion.

Blistering and scarring of the esophagus may lead to esophageal narrowing, making eating difficult. Your doctor may recommend surgery to widen (dilate) the esophagus. Using light sedation, the surgeon positions a small balloon in the esophagus and inflates it to dilate the area.

If feeding is impossible, a tube (gastrostomy tube) may be implanted to deliver food directly to the stomach. Feedings through the tube may be delivered overnight using a pump.

Physical therapy
Working with a physical therapist can help ease the limitations on motion caused by scarring and contracture.

It's not possible to prevent epidermolysis bullosa, but you can take steps to help prevent blisters, for yourself or for your child.

• Handle your child gently. Your infant or child needs your touch, but be very gentle. To pick up your child, place him or her on soft material, such as cotton, and support under the buttocks and behind the neck. Don't lift your child from under his or her arms.
• Moderate the temperature in your home. Set your thermostat so that your home remains cool and the temperature remains steady.
• Keep your child's skin moist. Gently apply lubricants, such as petroleum jelly.
• Dress your child in soft materials. Use clothing that's simple to get on and off.
• Trim your child's fingernails regularly. Short fingernails will help prevent scratching.
• Have your child refrain from rough activities. Prevent older children from participating in contact sports or other activities in which skin can be rubbed or injured easily.
• Take care when dressing blisters. Don't apply adhesive bandages or tape to the skin.
• Avoid hard surfaces and rough materials. Use sheepskin or other soft material on car seats and infant seats. Use a water or air mattress on your child's bed and soft sheets and blankets.

Careful wound care and good nutrition are essential to your health and your child's health. If blisters are left intact, they can grow, which creates a bigger wound when they finally break. Talk to your doctor about safe ways for you to break and drain blisters before they get too large. Your doctor also can recommend products you can use to keep the affected areas moist to promote healing, such as gauze that contains a moisturizing agent, and prevent infection.

Keep these in mind when tending to your child's wounds:

• Always wash your hands before touching your child's blisters.
• If a soiled dressing sticks, don't pull it off. Soak the area in warm water until the dressing loosens.

If oral or esophageal blisters are inhibiting your child's ability to eat, here are some suggestions:

• If drinking from breast or bottle causes your infant to develop blisters, try using nipples designed for premature infants or infants with cleft palate, a facial birth defect, or use a syringe or eyedropper.
• For older children, puree foods with extra liquid, such as broth or milk, to make them softer.
• Serve soft, nutritious foods such as vegetable soups and fruit smoothies.

Caring for a child with a chronic disease can be stressful. And providing your child with the emotional support needed to live with a chronic illness and to deal with being different from other children can be extremely difficult. For some people, sharing concerns and information with families in similar circumstances can be beneficial.

Ask your health care providers for epidermolysis bullosa support groups in your area. If a joining a support group isn't for you, ask about counselors, clergy or social workers who work with families coping with epidermolysis bullosa.