Every main type can again be divided into several variations. Currently, 27 clinical variations and disorders in half a dozen adhesion molecules are known. This home care programme only describes the main types of EB:

• EB Simplex;

• Junctional EB;

EB Simplex is characterized by dissolution of the skin right above the basement membrane, the basal layer. Approximately 70% of all EB-sufferers suffer from EB simplex.

Most forms of EB simplex are inherited as dominant traits. Because of this, the family history has already shown that there is a possibility to get a child with EB simplex. However, sometimes a patient is confronted with the disorder for the first time, a so-called new mutation.

EB simplex in which blistering is confined to hands and feet is most common. These patients usually do not seek medical assistance because the disorder is mild and because it is well known in the family due to the dominant inheritance. In another form of EB simplex blistering can occur all over the body. Blistering may appear during the neonatal period but it can also manifest itself in later childhood (or even in adult life). Rubbing tends to be the main cause for blistering and especially rubbing of the feet by footwear. Rubbing is worse in warm weather.

Junctional EB is characterized by dissolution of the skin through the basement membrane. Of all EB-sufferers approximately 10% suffer from junctional EB. Junctional EB is recessive inheritable. The parents are carriers, often unknowingly. The birth of a child with junctional EB is totally unexpected.

The outlook of junctional EB is usually rather bleak; half of the children die within the first two years as the result of malnutrition and anaemia which are caused by serious blistering in the pharynx and the oesophagus. Characteristic clinical features are the cutaneous defects with formation of hypergranulation tissue on the face. These cutaneous defects only develop after a couple of months. There are only a few patients with this severe type that survive the second or third year of life. The other half of the children have a milder form of junctional EB which does not impose life restrictions.

Dystrophic EB is characterized by a dissolution of the skin under the basement membrane. Approximately 20% of all EB-sufferers suffer from dystrophic EB. The dystrophic type may be inherited as a dominant or a recessive trait. The recessive inheritable types may lead to major handicaps and a relatively short and painful life. However, there are many exceptions to this rule.

Dystrophic EB derives its name from the tendency of the blisters to heal with atrophic scarring. This process can lead to joint contractures, fusion of the fingers and toes, contraction of the mouth and stenosis of the oesophagus. There is a wide variation in the severity of dystrophic EB. In general, dystrophic EB is not life-threatening in childhood. At its least severe (this is often the dominant inheritable type of dystrophic EB) the patient can lead an almost normal life. However, the severity of the disorder does increase at a later age due to scarring, fusions and dystrophy.