Definition of Epidermolysis bullosa:

Epidermolysis bullosa is a group of inherited disorders in which skin blisters develop in response to minor injury.

Causes, incidence, and risk factors:

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.