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)

1. Bauer JW et al (2003) Type XVII collagen gene mutations in junctional epidermolysis bullosa and prospects for gene therapy. Clin Exp Dermatol 28: 53-60
2. Bichel J et al (2001) Large melanocytic nevi in generalized atrophic benign epidermolysis bullosa (epidermolysis bullosa nevi). Dermatologist 52: 812-816
3. Castiglia D et al (2001) Novel mutations in the LAMC2 gene in non-Herlitz junctional epidermolysis bullosa: effects on laminin-5 assembly, secretion, and deposition. J Invest Dermatol 117: 731-739
4. Fine JD et al (2000) Revised classification system for inherited epidermolysis bullosa: report of the Second International Consensus Meeting on diagnosis and classification of epidermolysis bullosa. J Am Acad Dermatol 42:1051-1066.
5. Fine JD et al (2008) The classification of inherited epidermolysis bullosa (EB): Report of the Third International Consensus Meeting on Diagnosis and Classification of EB. J Am Acad Dermatol 58:931-950.
6. Fivenson DP et al (2003) Graftskin therapy in epidermolysis bullosa. J Am Acad Dermatol 48: 886-892.
7. Guerriero C et al (2001) Non-Herlitz junctional epidermolysis bullosa without hair involvement associated with BP180 deficiency. Dermatology 202: 58-62
8. Hashimoto I, Schnyder UW, Anton-Lamprecht I (1976) Epidermolysis bullosa hereditaria with junctional blistering in an adult. Dermatologica 152: 72-86
9. Herlitz O (1935) Congenital nonsyphilitic pemphigus: a review together with a description of a new form of the disease. Acta Paediat 17: 315-371
10. Höger P (2005) Pediatric dermatology. Schattauer Verlag Stuttgart p 225-226
11. Huber A et al (2002) Comprehensive analysis of gene expression profiles in keratinocytes from patients with generalized atrophic benign epidermolysis bullosa. Exp Dermatol 11: 75-81
12. Jonkman M et al (1996) Generalized atrophic benign epidermolysis bullosa: either 180 kD bullous pemphigoid antigen or laminin 5 deficiency. Arch Dermatol 132: 145-150
13. Nakano A et al (2002) Junctional epidermolysis bullosa in the Middle East: clinical and genetic studies in a series of consanguineous families. J Am Acad Dermatol 46: 510-516.
14. Yancey KB et al (2010) Non-herlitz junctional epidermolysis bullosa. Dermatol Clin 28: 67-77.