Epidermolysis bullosa

Description

Epidermolysis bullosa or EB (also known as "butterfly disease") is a group of genetic skin diseases which can be inherited as either autosomal dominant or recessive. The skin of those affected is very fragile, forming blisters spontaneously or from even light contact or minimal mechanical interactions (friction, pressure, injury) on the skin. The skin may be more or less sensitive, depending on the type of disease. EB is hereditary, with increased blister formation arising from inadequate anchoring of the upper skin layer to the underlying ones. This is due to a defective or missing gene that controls the formation of a protein essential for this purpose. The disease is divided into four main forms, depending on the level at which blisters form in the skin: EB simplex (EBS, with blisters in the basal keratinocyte layer), Junctional EB (JEB, with blisters along the basement membrane), Dystrophic EB (DEB, with blisters beneath the basement membrane) and Kindler syndrome (KS, with multiple blister levels). Thus far, more than 18 genetic defects are known which may lead to EB. A precise diagnosis and classification of the EB type is possible through two techniques: immunofluorescence mapping of a skin sample and mutation analysis of the blood.

Symptoms

Due to deficient anchoring of the skin layers, even very slight mechanical stress increases the tendency of the skin to blister. This mainly involves the skin on the hands and feet, but also the mucous membranes (e.g. in the mouth and eyes) and membranes of the digestive tract. These blisters can be filled with blister secretions or blood, depending on the depth of the affected skin layers. If the deeper layers are affected, the healing process of the resulting wounds often leads to scarring and adhesions, which in turn can cause contractures (e.g. of the hands and feet).

EB simplex is normally mild in form. Healing of the blisters usually occurs without scarring and skin atrophy. Blister formation usually occurs more during childhood than in adulthood.

Junctional EB has both mild as well as early lethal forms. Healing without scarring is usually observed, however skin atrophy often occurs.

Dystrophic EB can either take a mild or a more severe form. Healing without scars is rare, because the deeper skin layers are affected by blistering. In severe cases, bad scarring can cause mutilation of the hands and muscle contractures.

The level of blistering in the skin cannot be determined externally. Therefore, the removal of a skin sample for immunofluorescence mapping study is necessary.

Other possible complications for EB sufferers can include malnutrition, missing nails, adhesion of the skin on hands and feet, tooth decay, alopecia, pain, and skin cancer, among others.

Examination and Diagnosis

As a rule, the disease is indicated by characteristic EB blisters which appear already at or shortly after birth. After collecting the family history, skin samples are removed and analyzed by immunofluorescence mapping to make an initial EB diagnosis. Using this method, the most important proteins on the patient's skin that may be affected by EB are stained and then evaluated under a microscope. This analysis shows whether a protein is absent or not functional. The diagnosis is completed by mutation analysis of the affected gene in the blood. Only after this can the initial diagnosis be confirmed and a prognosis made.

Treatment

Currently there is no cure for, and no treatment for the causes of, Epidermolysis bullosa. However, relief and a significant reduction in the signs and symptoms can be achieved. Furthermore, early identification of problems and adequate therapy can forestall, reduce or avoid certain complications. Because the group of Epidermolysis bullosa diseases in their various sub-forms may affect many other organs besides the skin, collaboration and joint medical supervision is necessary between the patient, their family, various medical occupation groups and a range of professional disciplines. But with milder forms of EB, supervision through the family and by the patient himself is often sufficient.

In some cases, daily care must to be taken over by professionals. Additionally, the supervision of a children's or family doctor and skin doctor is essential. In many cases specialized dentists, gastroenterologists, surgeons and orthopedic surgeons together with physical therapists, dieticians, social workers, psychologists, etc must be brought in. Only in this way can optimal support in sometimes complex problem situations be achieved.

The symptomatic treatment of wounds is at the forefront in daily life. In addition to regular care of wounds, sometimes several times a day, treatments with antibiotics and antihistamines as well as iron or vitamin supplements are employed with EB. A change in diet is also frequently recommended. The decision about the particular treatment should always be left to the attending physicians.

Course and Prognosis

Epidermolysis bullosa is not a contagious disease but can - depending on the particular subtype - lead to significant impairment in quality of life, disability and even premature death of the person affected.

With certain forms of the disease, other organs may be affected in addition to the skin, so optimal support is based on the close collaboration between the patient, the patient's family and the attending physicians.

Miscellaneous/Other Comments

In the Epidermolysis Bullosa Center Freiburg, patients are examined using the latest methods and their skin problems are treated by specialists. Potential organ manifestations are treated through interdisciplinary collaboration with other clinics at the Medical Center - University of Freiburg.