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Prevalence is unknown. To date, 52 cases have been reported.

The disease usually manifests at birth, or soon after. Skin blisters generally affect the whole body. Blisters can also affect the oral cavity. Healing of blisters is associated with mild, mostly atrophic, scarring and milia formation. Disease activity usually ceases within the first 6 to 24 months of life, although there are a few cases with continued blistering past age 3 years. Nail dystrophy and some degree of skin fragility can persist in adulthood. Ultrastructurally, the presence in basal keratinocytes of peculiar cytoplasmic inclusions, known as stellate bodies, filled with unsecreted procollagen VII, is typical of the disease.

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

Diagnosis is based on identification of granular intraepidermal type VII collagen by immunofluorescence mapping and electron-dense stellate bodies on ultrastructural examination. Genetic testing can confirm diagnosis.

The differential diagnosis includes other types of epidermolysis bullosa.

Because of the mild course of the disease, antenatal diagnosis is usually not required.

Genetic counseling will depend on the mode of inheritance which can be autosomal dominant or recessive.

Treatment is symptomatic with wound care to prevent secondary infection and reduce scarring.

Overall the prognosis is good.