What is Epidermolysis Bullosa?
Epidermolysis bullosa (EB) simplex is a rare inherited disorder where skin becomes thin and fragile, causing it to blister at sites of friction. It ranges in severity from mild to severe, which is usually categorised in the following ways:
- Localised EBS: This is the most mild and common form of EBS. Blisters develop on the hands and feet in response to friction. It usually first presents in infancy, and becomes more troublesome in warm weather.
- Generalised EBS: Blisters can appear on any part of your body, but are more common on the extremities. This also presents from birth or in early infancy. It may also cause thickening of nails, and thick plaque to develop on palms and soles of feet.
- EB Simplex Dowling-Meara: This is a more severe form of EBS, It is present from birth with blistering on the face, back, and limbs. In the most severe cases blistering may also affect the mouth, respiratory tract and organs. Nails are often affected, and thickened skin may cause difficulty with joint movement.. This form can be life limiting, or even lethal in early infancy, but generally improves with age.
Other forms of the condition include:
- Dystrophic epidermolysis bullosa (DEB), Kindler Syndrome, and Junctional epidermolysis bullosa (JEB). JEB is the most severe type and usually proves lethal within the first 12-24 months of life due to related complications such as infection, malnutrition and dehydration as blisters affect the oesophagus.
What are the symptoms of Epidermolysis Bullosa ?
Blisters present differently depending on the form of the condition. With EB Simplex, both localised and generalised, the blisters look like friction blisters, the same as you would get from poorly fitted shoes. They vary in size and can be up to 2cm in size. They heal without scarring.
Blisters that appear from the Dowling-Meara variant tend to occur in clusters and will generally leave some scarring, or pigmentation on the skin. This form also causes a thickening of skin on the palms and soles, and nails.
Blisters can appear at any part of the body but are much more common at sites of friction such as hands and feet.
In more severe sub types such as Dowling Meara, JEB, and DEB blistering can also affect internal organs such as the oesophagus, stomach and respiratory tract.
What causes Epidermolysis Bullosa?
It is a genetic condition that is a result of a genetic defect of molecules in the skin causing a loss of adhesion. This results in blister formation.
The type of EB that patients inherit depends on which layer of skin is the site of blister formation.
Who is at risk of Epidermolysis Bullosa?
EB is inherited, meaning that you have to have one or more inherited EB genes. In the case of autosomal dominant EB, only one of your parents need to have the condition for it to be inherited. Whilst, autosomal recessive inherited EB requires you to have two EB genes (one from each parent) to have the disease.
Males and females are equally likely to inherit the condition. It usually presents at birth or shortly after, although is rare cases it may be too mild to detect in childhood and may only be detected later.
How does a dermatologist diagnose Epidermolysis Bullosa ?
A Dermatologist diagnoses EB based on appearance, distribution of blisters, and family history.
If there is any uncertainty about the diagnosis, a dermatologist may perform a skin biopsy to send to a specialist laboratory for more detailed microscopic examination.
A blood test may also be suggested to look for gene abnormalities. Professor Jemima Mellerio is a specialist Dermatologist in blistering and genetic skin disease and we would recommend appointments with her for this condition.
How does a dermatologist treat Epidermolysis Bullosa?
There is no cure for EB. Dermatologist advice focuses on improving the quality of life through protecting the skin, reducing blister formation, promoting healing of the skin, and avoiding complications.