Epidermolysis bullosa junctionalis generalized intermediaries (non-herlitz)Q81.1

Hereditary, generalized, non-lethal, blistering dermatosis with spontaneous and post-traumatic blistering (formation of a cleft along the basement membrane) Low esophageal involvement. There is an increased tendency to develop epithelial malignancies (squamous cell carcinomas).

Incidence at 1:50,000

Autosomal recessive mode of inheritance. Homozygous or "compound" heterozygous mutations in the gene for collagen XVII (COL17A1, BPAG2) located on chromosome 10q24.3 are discussed (most gene defects are null mutations leading to absence of the gene product collagen type XVII in the skin) as well as of the laminin genes LAMA3, LAMB3,LAMC2 (especially LAMB3).

Integument:

• Mostly generalized clinical picture (see fig.) with the formation of recurrent, extensive, flaccid, also turgid blisters of different sizes with serous or hemorrhagic contents as well as erosions, which usually heal without further mutilations with bizarrely configured, reddish-brown pigmentation or whitish atrophies. Blistering occurs after trivial trauma, but also episodically spontaneously (Fine JD et al 2008) . Less commonly, milia are observed during healing.
• In case of head infestation mostly follicular atrophies leading to extensive alopecia especially at the parietal capillitium. Frequent onychoatrophy or onychodystrophy.

Extracutaneous manifestations:

• Involvement of the eyes is found in 40-50% of patients (blisters, scarring ectropia, corneal or conjunctival erosions - see also under: Epithelial recurrent erosive dystrophy).
• Compared to EBJ-H, only minor involvement of oral mucosa and esophagus.
• Occasionally - formation of melanocytic nevi.
• Growth retardation
• Hypoplasia of enamel or tooth growth with increased susceptibility to caries.

Subepidermal blistering: Bullous detached epidermis with well preserved basal cell row in the blister roof. Distinct lymphohistiocytic infiltrates in the upper corium.

Electron microscopy: Junctiolytic blister formation.

Decreased fluorescence of laminin-5 and collagen XVII at the bladder roof.

Avoidance of mechanical trauma, positioning on special air or water padded beds, soft clothing, wearing clothes from the left side if necessary to avoid chafing effects at the seams.

Careful personal hygiene with disinfecting baths and sterile covering of blisters and erosions.

Diagnostics: Clinical, histology, immunofluorescence, electron microscopy, molecular genetic examination, prenatal diagnostics if necessary. There is an increased risk of malignant development of the skin(squamous cell carcinoma of the skin, rarely malignant melanoma)

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