Types of EB

Epidermolysis bullosa refers to a group of disorders that involve the formation of blisters following trivial trauma. Over 300 mutations have been identified in this condition. They have been classified into the following types:

Epidermolysis bullosa simplex

Epidermolysis bullosa simplex is a form of epidermolysis bullosa that causes blisters at the site of rubbing. It typically affects the hands and feet, and is typically inherited in an autosomal dominant manner, affecting the keratin genes KRT5 and KRT14.Therefore, there is a failure in keratinisation, which affects the integrity and the ability of the skin to resist mechanical stresses.

Junctional epidermolysis bullosa

Junctional epidermolysis bullosa is an inherited disease affecting laminin and collagen. This disease is characterised by blister formation within the lamina lucida of the basement membrane zone[9]:599 and is inherited in an autosomal recessive manner. It also presents with blisters at the site of friction, especially on the hands and feet, and has variants that can occur in children and adults. Less than one person per million people is estimated to have this form of epidemolysis bullosa.

Dystrophic epidermolysis bullosa

Dystrophic epidermolysis bullosa is an inherited variant affecting the skin and other organs. Dystrophic epidermolysis bullosa is caused by genetic defects (or mutations) within the human COL7A1 gene encoding the protein type VII collagen (collagen VII). DEB-causing mutations can be either autosomal dominant or autosomal recessive. Epidermis bullosa pruriginosa and Albopapuloid epidermolysis bullosa (Pasini’s disease) are rare subtypes of this disease.