Chapter 9: Genodermatoses
Genodermatoses: Epidermolysis Bullosa
Epidermolysis bullosa (EB) is a family of blistering skin diseases in which the components of skin adhesion are not able to function properly due to genetic alterations.
EB is roughly broken into 3 classifications based on location of the resultant blister within the skin:
EB Simplex (EBS): Blisters form within the epidermis, most commonly due to mutations in keratins. Most cases of EBS are inherited in an autosomal dominant fashion or represent new mutations. Symptoms range from mild blistering on the hands and feet to much more widespread, but superficial blistering. Blisters tend to be worse in warm conditions. The most severe types can also be associated with significant itching.
Junctional EB: Blisters form with the dermal-epidermal junction due to alterations in the structural proteins in the basement membrane. Junctional EB is further divided into lethal and non-lethal forms, with lethal junctional EB having a life-expectancy of only about 1 year.
Dystrophic EB (DEB): Blisters for beneath the dermal-epidermal junction due to mutations in Collagen 7. Both dominant (DDEB) and recessive (RDEB) forms of dystrophic epidermolysis bullosa exist. Due to depth of blisters, these often heal with milia formation and scarring. Patients with RDEB have quite severe blistering that requires protection and frequent dressing changes. They are at risk of infection, severe pain, scarring, and eventually squamous cell carcinoma formation. Due to blistering of mucosa, they often have oral sores, challenges with dentition and the need for periodic esophageal dilation due to stricture formation.
Wound care is crucial for patients with EB and the appropriate plan for wound care depends on the phenotypic presentation of the disease. A multidisciplinary team, which might include general pediatrics, dermatology, gastroenterology, dental, pain control and plastic surgery, is often helpful in providing the necessary care to affected children.
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