Background Information About Epidermolysis bullosa

BACKGROUND: Epidermolysis bullosa (EB) is a rare genetic disease characterized by incredibly fragile skin tissue and recurrent blister formation from minor friction or trauma. The severity of the condition varies depending on the form (Simplex EB, Junctional EB, Recessive Dystrophic, or Dominant Dystrophic). The latest figures from the national EB registry find the condition affects less than 10,000 children and adults in the United States. It occurs in all racial groups and genders in equal numbers. Infancy is an especially difficult time for patients with EB. Blistering can be caused by the slightest touch of skin, clothing or, in severe cases, air. The blisters can lead to infection, sepsis and even death. Severe forms of EB increase the risk of mortality during infancy -- patients with the Herlitz or Letalis form of juvenile EB have the highest risk of 87 percent during the first year of life.

Patients with EB lack anchors that hold the layers of skin together. Any activity that rubs or causes pressure to the skin results in painful sores and blisters. Even bathing these children is difficult because water touching the open wounds causes incredible pain and washing the skin can lead to further blistering. Many patients must live on a liquid diet or eat only soft foods because the esophagus can also blister. Over time, repeated healing and scarring on the hands and feet can cause the tissue to form "stumps" where the tissue has overgrown the digits. The condition can also lead to squamous cell carcinoma -- an aggressive skin cancer.

TREATMENT: Many parents find bandaging children with gauze and ointment from head to toe can prevent skin damage. However, damage can still occur beneath these bandages because pressure can also lead to the painful wounds. While ointments and skin grafts have shown some success and are being tested to see if they will help treat the disease, there is no known cure or treatment for EB. New stem cell therapy is being tested at the University of Minnesota by way of bone marrow transplants from healthy people who are matches to patients with EB. A 100 day trial is currently underway in Minnesota to find out if the treatment worked for a young boy with the disease. Results are not yet available, but both doctors and the boy's family are hopeful and feel they have seen some progress so far.

PASSING ON EB: The genes that cause EB can be either dominant or recessive. The dominant forms (Simplex and Dominant Dystrophic) are caused when a parent is a carrier of the dominant gene. A dominant carrier parent has a 50 percent chance of transmitting the abnormal gene with each pregnancy. Rarely, children can be born with a genetic mutation that causes the disease when neither parent is a carrier. The affected child will also have a 50 percent chance of passing the disease to his or her children.

Junctional and Recessive Dystrophic EB conditions are caused by a recessive gene expression. If both parents are carriers of the unexpressed gene, with each pregnancy, they have a 25 percent chance of the genes expressing themselves in the child, causing EB.


University of Minnesota Pediatrics