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Prevalence is unknown. Approximately 100 families or sporadic cases have been reported to date, but it might be underreported.

While skin fragility and blistering lesions usually manifest in infancy, which heal with atrophic scarring and milia formation, the onset of intense pruritus is frequently delayed until the adolescence or even adulthood. At the onset of pruritus, the clinical picture generally worsens with the development of papules, nodules, lichenoid and hypertrophic lesions in a linear distribution, preferentially on the extensor surfaces of the limbs. Nail dystrophy is usually present.

DEB pruriginosa is caused by mutations within the type VII collagen gene (COL7A1/i>; 3p21.31). Mutations in this gene lead to an alteration in function or to reduced amounts of collagen VII. This impairs its assembly into anchoring fibrils that anchor the basement membrane to the underlying dermis.

Transmission electron microscopy shows blister formation below the lamina densa and reduced number of anchoring fibrils in adjacent non-blistered skin. Immunofluorescence mapping shows dermal cleavage of the skin and reduced immunoreactivity for type VII collagen. The diagnosis is confirmed by genetic testing.

Differential diagnosis includes nodular prurigo, lichen simplex, lichen planus, hypertrophic scarring and dermatitis artefacta.

Antenatal diagnosis is not recommended.

The disorder is typically sporadic but autosomal dominant and recessive inheritance has also been reported. Genetic counselling should be offered to affected individuals informing them of risk of transmitting the pathogenic variant to offspring.

Clinical management of DEB pruruginosa is often difficult, although generic measures reduce itching. Nevertheless, there are some reports of helpful interventions which include topical treatments (e.g. tacrolimus), systemic agents (e.g. ciclosporin or thalidomide), and cryotherapy. Recently, dupilumab has proven to be effective.

The condition is therapy resistant, but the overall course of the disease is mild to moderate and life expectancy is normal.