A Case Study of Epidermolysis Bullosa

By: Laurie S. Longe

EB is a disorder in which painful blistering affects the skin. Non-scarring forms may depend on the weather or temperature, and often appear on the hands and feet. The scarring varieties consist of open sores and blisters which can lead to disfigured, or mittened hands and feet, scar tissue in the mouth, or infection in the digestive organs.
The Simplex form of EB is inherited as an autosomal dominant trait, while both the Dystrophic illness and the Basement Membrane disorder are recessive forms of the mutation. In EB Simplex, a mutation in a gene on chromosome number five, which encodes keratin, is affected. In the Dystrophic illness, the gene encoding collagen is affected. This results in difficulties in connecting the dermis and epidermis. In the Basement Membrane disorder, anchoring of the epidermis to the basement membrane by the protein epiligrin is affected. Although all three types of EB discussed above have different causes, their symptoms are similar; the diseases manifest themselves in painful blisters and sores. Both the Dystrophic type and the Basement Membrane disorder deal with anchoring of the skin layers due to lack of a specific protein. Though the EB illnesses vary in genotype, the phenotype is similar. In each case, a lack of proteins in the skin yield mutation. Perhaps it is due to the lack of vital proteins in the skin layers which lead to the intense blistering of the skin.
Because EB Simplex is a dominant trait, a parent with the affected gene has a fifty percent chance of having a child with EB, regardless of sex or birth order. In the recessive traits of EB, the child needs to inherit an EB recessive gene from each parent in order to have the disease, (fifty percent.) A child who inherits only one gene for recessive EB will be a carrier for EB, (twenty-five percent.) The chance of EB carrier parents having a normal child who is not an EB carrier is twenty-five percent. (This is also regardless of sex or birth order.)
One in fifty thousand infants is born with EB. Gene therapy is a possibility for EB patients who have the Simplex form of the virus. Keratinocytes can grow in culture, accept foreign genes, and be grafted onto a person. This is beneficial to EB Simplex patients because the mutation occurs in the epidermis. In the Dystrophic and Basement Membrane forms of EB, tissue beneath the epidermis is affected. In the Dystrophic form, the fibers anchoring the dermis to the epidermis are affected. Due to the fact that connective tissue and proteins beneath the epidermis are damaged, the act of simply grafting them onto a person would not be affective for patients diagnosed with these two types of EB.
Treatment for EB consists of minimizing infection due to open sores and blisters, and replacement of lost fluid. Specially cushioned shoes should be worn to minimize foot pain. Scar tissue may be surgically removed in some cases. Pertaining to the Dystrophic illness, current research indicates that EB patients manufacture high levels of collagenases. Injections of collagen have led to decreased blistering in some cases. However, there is no cure as of yet for EB. Many EB patients develop cancer, malnutrition, and infections due to oral scar tissue and sores in the digestive system.


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2.) Lin, A. and Carter, D. Epidermolysis Bullosa: Basic and Clinical Aspects.
Springer-Verlag, NY; 1992.

3.) Priestley et. al. Epidermolysis Bullosa: A Comprehensive Review of
Classification, management, and Laboratory Studies.
DEBRA, Crowthorne, UK; 1990.

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