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Epidermolysis bullosa
Definition
Epidermolysis bullosa is a group of inherited disorders in which skin blisters develop in response to minor injury.
Alternative Names
Junctional epidermolysis bullosa; Dystrophic epidermolysis bullosa; Hemidesmosomal epidermolysis bullosa; Weber-Cockayne syndrome
Causes
There are four main types of epidermolysis bullosa:
- Dystrophic epidermolysis bullosa
- Epidermolysis bullosa simplex
- Hemidesmosomal epidermolysis bullosa
- Junctional epidermolysis bullosa
Another rare type of epidermolysis bullosa called epidermolysis bullosa acquisita, is an autoimmune disorder. It may be difficult to tell this condition apart from another autoimmune skin disorder called mucous membrane pemphigoid.
Identifying the exact type of epidermolysis bullosa is complicated. Even within the main types listed above, there are many subtypes. For example, Weber-Cockayne is the most common form of epidermolysis bullosa simplex. This type involves blistering of the palms and soles and may include excess sweating.
Epidermolysis bullosa can vary from minor blistering of the skin to a lethal form involving other organs. The condition generally starts at birth or soon after.
Epidermolysis bullosa acquisita usually appears in adults over age 50, although it can occur in children. It is linked to Crohn's disease (an inflammatory bowel disease) and possibly lupus. Adults with this type of epidermolysis bullosa may also have symptoms of these other conditions.
Mild cases of epidermolysis bullosa simplex may not be diagnosed until adulthood.
All types of epidermolysis bullosa are usually inherited. Having a family history of the disease, and especially having a parent with it, is a risk factor.
Symptoms
Symptoms depend on the type of epidermolysis bullosa, but can include:
- Alopecia (hair loss)
- Blisters aound the eyes and nose
- Blisters in or around the mouth and throat, causing feeding problems or swallowing difficulty
- Blisters on the skin as a result of minor injury or temperature change
- Blistering that is present at birth
- Dental problems such as tooth decay
- Hoarse cry, cough, or other breathing problems
- Milia (tiny white bumps or pimples)
- Nail loss or deformed nails
Exams and Tests
Your doctor may suspect epidermolysis bullosa based on the appearance of the skin.
Tests that are used to confirm the diagnosis:
- Genetic testing
- Skin biopsy (usually with immunofluorescent tests or electron microscopy)
- Special microscopic tests of skin samples
Special skin tests are used to tell epidermolysis bullosa acquisita in a child from other forms of epidermolysis bullosa.
Other tests that may be done:
- Blood test for anemia
- Culture to check for bacterial infection if wounds are healing poorly
- Upper endoscopy or an upper GI series if there are swallowing or feeding difficulties
Growth curves will be carefully watched in an infant who has, or is believed to have epidermolysis bullosa.
If there are contractures, limb range of motion will be tested.
Treatment
The goal of treatment is to prevent blisters from forming and complications. How much treatment is needed depends on how severe the disease is. Recommendations often include avoiding skin damage (trauma) and hot environments.
- To prevent infection take very good care of the skin, especially if any blistered areas become crusted or exposed (raw). Follow your health care provider's instructions closely. You might need regular whirlpool therapy and to apply antibiotic ointments to wound-like areas. Your health care provider will let you know if you need a bandage or dressing, and if so, what type to use.
- For swallowing difficulties, your may need to use oral steroids for short periods of time. Long-term steroids for epidermolysis bullosa is generally not recommended. If you also have candida in the mouth or esophagus, you will also need to take medication for that infection.
- Good dental hygiene is very important, including regular dental visits. It is best to see a dentist who has experience treating people with epidermolysis bullosa.
- Proper nutrition is also important. When you have a lot of skin injury, you may need extra calories and protein to help you recover. Work closely with a nutritionist. If you have blisters or complications in the mouth or esophagus, avoid eating hard or brittle foods such as pretzels, nuts, and chips. Eating soft foods can help prevent making the sores worse.
- Working with a physical therapist can help you keep the full range of motion in the joints and minimize contractures.
Skin grafting for denuded or ulcerated areas of the skin may be necessary. Other surgical procedures for complications of epidermolysis bullosa might be recommended. Such surgeries include:
- Dilation of the esophagus if there is a narrowing (stricture)
- Repair of hand deformities
- Removal of of any squamous cell carcinoma that develops
Other treatments under investigation for epidermolysis bullosa include protein and gene therapy.
Epidermolysis bullosa acquisita may be treated with oral steroids and medication that suppresses the immune system. These may, however, increase the risk of infection or damage the liver or kidneys. Studies using interferon are also under way.
Outlook (Prognosis)
The outlook depends on the severity of the illness. Mild forms of epidermolysis bullosa improve with age.
In the severe forms, scarring after blisters form may cause:
- Contracture deformities (for example, at the fingers, elbows, and knees) and other deformities
- Feeding and swallowing difficulties if the mouth and esophagus are involved
- Fused fingers and toes
- Restricted mobility from scarring
Very serious forms of epidermolysis bullosa have a very high mortality rate.
Secondary infection is common.
Possible Complications
- Anemia
- Death (junctional epidermolysis bullosis has a high death rate, but other, milder forms may not reduce life expectancy at all)
- Esophageal stricture
- Eye disorders, including blindness
- Infection, including sepsis
- Loss of function in the hands and feet
- Muscular dystrophy
- Periodontal disease
- Severe malnutrition caused by feeding difficulty, leading to failure to thrive
- Squamous cell skin cancer
When to Contact a Medical Professional
If your infant has any blistering shortly after birth, call your health care provider. If you have a family history of epidermolysis bullosa and plan to have children, you may want to have genetic counseling.
Prevention
Genetic counseling is recommended for prospective parents who have a family history of any form of epidermolysis bullosa.
During pregnanc, chorionic villus sampling to test the fetus is available. For couples at high risk of having a child with epidermolysis bullosa, the test can be done as early as week 8 - 10 of pregnancy. Talk to your obstetrician and genetic counselor.
To prevent skin damage and blistering, it may help to wear padding around injury-prone areas such as the elbows, knees, ankles, and buttocks. Contact sports should be avoided.
Patients with epidermolysis bullosa acquisita who are on steroids for longer than 1 month may need calcium and vitamin D supplements to prevent osteoporosis.
References
Vesicular and bullous diseases. In: Habif TP, ed. Clinical Dermatology. 5th ed. Philadelphia, Pa: Mosby Elsevier;2009;chap 16.
Morelli JG. Vesiculobullous disorders. In: Kliegman RM, Behrman RE, Jenson HB, Stanton BF, eds. Nelson Textbook of Pediatrics. 18th ed. Philadelphia, Pa: Saunders Elsevier;2007:chap 653.
Reviewed By: Linda J. Vorvick, MD, Medical Director, MEDEX Northwest Division of Physician Assistant Studies, University of Washington, School of Medicine. Also reviewed by Kevin Berman, MD, PhD, Atlanta Center for Dermatologic Disease, Atlanta, GA. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.
