Dystrophic EB derives its name from the tendency of the blisters to heal with atrophic scarring. This process can lead to a number of problems including joint contractures, fusion of the fingers and toes, contraction of the mouth and stenosis of the oesophagus. There is both internal and external blistering. Involvement of the mucous membrane of the gastrointestinal tract is the most prominent feature in dystrophic EB. Besides the blistering related problems there are eye problems and (at a later age) squamous cell carcinoma.

Particularly the recessive inheritance type may cause pharyngeal problems. For example, because of involvement of the vocal cords by blistering. Swelling under the vocal cords can cause laryngeal restriction which may lead to serious shortness of breath. The dominant types of dystrophic EB present hardly any internal complaints.

The recessive inheritance type of dystrophic EB often leads to serious symptoms; the recovery of blisters often leaves scars, webbing and acquired syndactyly, contractures and impaired mobility. These features will be discussed below.

Even the most gentle skin contact may result in blistering. Many children with dystrophic EB are born with `eroded' body parts, especially on the feet and lower legs. This is probably the result of the baby's kicking with the legs in the uterus. Erosions are also caused by labour and the physical contact with the child immediately after the birth. The blisters tend to heal with scarring, microstomia, webbing and acquired syndactyly, contractures and impaired mobility.

A contracted mouth opening (microstomia) is caused by the progressive scarring of the skin of the corners of the mouth. This reduces the mouth opening which means the mouth can open less wide than usual. The microstomia can give cause for a reduced intake of solid foods, poor oral hygiene and problems with dental treatment.

The mobility of limbs may be impaired by `webbing' (the fusion of fingers and toes). This fusion is caused by the scarring of the skin which fuses the fingers and toes to each other. Before the webbing process, visible blistering is not always present. The webbing process can be somewhat slowed down by separately dressing the fingers.

Surgical separation of the fingers is often required to maintain at least the pick up-hold.

In the recessive inheritance type of dystrophic EB, posture and gait may be disrupted owing to the fear of falling. This is characterized by forward bent shoulders and head, a curvature of the spine and a deficient extension of the elbows, hips, knees and ankles.

Blistering in the mouth is a common feature in recessive dystrophic EB. This blistering can lead to:

• fixation of the tongue to the floor of the mouth (ankyloglossia) which may impair the speech;

• reduced secretion of saliva because of the involvement of the oral mucous membrane. This complicates the intake of solid food;

• reduced cleansing action of the teeth by the saliva;

• sensitive oral mucous membrane which causes eating and dental care to be painful.

Blistering and chronic erosions in the oesophagus result in scarring with various deformities and the restriction of the oesophagus. This complicates the food passage. Scarring is often present in the upper part of the oesophagus, sometimes with a complete obstruction. Because of this, there is a danger of malnutrition and a possibility of food aspiration with a fair chance of pneumonia.

Additionally, the involvement of the mucous membrane causes bleedings (especially in the oesophagus) and there is a chance of perforation of the mucous membrane.

Patients with recessive dystrophic EB run (due to, for example, strong wind or bright sunlight) the following risks: