What Is Junctional Epidermolysis Bullosa, LAMA3-related?
Junctional Epidermolysis Bullosa (JEB), LAMA3-Related is an inherited disease that causes severe blistering on the skin. There are two types of this condition: Herlitz JEB (H-JEB) and non-Herlitz JEB (NH-JEB). Both forms of JEB are caused by mutations in the LAMA3 gene.
Herlitz Junctional Epidermolysis Bullosa
Individuals with H-JEB lack anchors to hold the layers of their skin together. They develop large, fluid-filled blisters in response to any trauma, even something as minor as increased room temperature. Internal blistering on the lining of the nose, mouth, esophagus, trachea, rectum, stomach, intestines, and eyes are also present from birth.
Granulation tissue, a kind of soft, pink, bumpy, moist skin, forms at blistering sites in the healing process. It is also seen around the nose, mouth, ears, fingers, and toes, as well as in areas that receive friction, such as the buttocks and back of the head. Because this tissue can chafe and wear away, it bleeds easily, can be a site of fluid loss, and leaves the patient open to infection.
Other symptoms in infants and children with the disease may include a hoarse cry, cough, other breathing problems, fevers, loss of fingernails and toenails, poorly formed tooth enamel, abnormalities of the urinary tract and bladder (may lead to urinary tract infections and kidney failure), poor growth, electrolyte imbalance, hair loss, osteoporosis, and skin cancer.
Non-Herlitz Junctional Epidermolysis Bullosa
NH-JEB is a less severe form of H-JEB. Blistering occurs in fewer areas (hands, feet, knees, and elbows), and may not result in blistering of the internal organs. The onset of blistering may be later as well. Issues related to granulation tissue and complications with breathing are not common. However, hair loss, improper nail formation, and poorly formed tooth enamel are seen.
How Common Is Junctional Epidermolysis Bullosa, LAMA3-related?
H-JEB is extremely rare. Overall estimates indicate that 0.37 individuals per million are affected by H-JEB.
NH-JEB is slightly more common, with overall estimates of 2 individuals per million being affected by the disease.
How Is Junctional Epidermolysis Bullosa, LAMA3-related?
Symptoms are generally treated as they arise. It is best to protect the child as much as possible from skin damage. For example, a cesarean section may be recommended to protect the child from the skin trauma of birth, excess movement is avoided, and clothing that may damage the skin is avoided. When open wounds and blistered skin occur, they are often covered with multiple layers of non-adhesive bandages and anyone handling the child must use extreme care. Antibiotics and antiseptics are often prescribed to prevent and treat infections. For individuals with H-JEB, a dietitian should be consulted to ensure proper nutrition. To avoid dehydration, these children should also drink plenty of fluids.
In individuals with breathing difficulty (more typically those with H-JEB), an opening may be made in the neck to deliver air to the trachea. However, this may be difficult for a person with fragile skin.
What Is the Prognosis for an Individual with Junctional Epidermolysis Bullosa, LAMA3-related?
The prognosis for individuals with H-JEB or NH-JEB is poor and roughly 40-45% of individuals with either form of JEB die in the first year of life. Roughly 62% of individuals with H-JEB and 48% of individuals with NH-JEB die by age 15. This disease is extremely painful and causes of death often include impaired physical growth (failure to thrive), infection, and respiratory failure.