Junctional epidermolysis bullosa (medicine)
| Junctional epidermolysis bullosa (medicine) | |
|---|---|
| Specialty | Medical genetics  |
Junctional epidermolysis bullosa is a skin condition characterized by blister formation within the lamina lucida of the basement membrane zone.[1]: 599
Classification
| OMIM | Name | Locus | Gene |
|---|---|---|---|
| Template:OMIM2 | Junctional epidermolysis bullosa with pyloric atresia | 17q11-qter, 2q31.1 | ITGB4, ITGA6 |
| Template:OMIM2 | Junctional epidermolysis bullosa, Herlitz type | 18q11.2, 1q32, 1q25-q31 | LAMA3, LAMB3, LAMC2 |
| Template:OMIM2 | epidermolysis bullosa, junctional, non-Herlitz types (Generalized atrophic benign epidermolysis bullosa, Mitis junctional epidermolysis bullosa) | 18q11.2, 1q32, 17q11-qter, 1q25-q31, 10q24.3 | LAMA3, LAMB3, LAMC2, COL17A1, ITGB4 |
Junctional epidermolysis bullosa with pyloric atresia
Junctional epidermolysis bullosa with pyloric atresia is a rare autosomal recessive form of junctional epidermolysis bullosa that presents at birth with severe mucocutaneous fragility and gastric outlet obstruction.[2]: 557 It can be associated with ITGB4 or ITGA6.[3]
Herlitz type
Junctional epidermolysis bullosa gravis (also known as "Herlitz disease," "Herlitz syndrome," and "Lethal junctional epidermolysis bullosa") is the most lethal type of epidermolysis bullosa, a skin condition in which most patients do not survive infancy, characterized by blistering at birth with severe and clinically distinctive perorificial granulation tissue.[1]: 599 [2]: 557 [4]
JEB-H is generally caused by mutations in one of the three laminin-332 coding genes: LAMA3 (18q11.2), LAMB3 (1q32) and LAMC2 (1q25-q31).
Non-Herlitz type
These include:
- Generalized atrophic benign epidermolysis bullosa is a skin condition that is characterized by onset at birth, generalized blisters and atrophy, mucosal involvement, and thickened, dystrophic, or absent nails.[1]: 600 [2]: 557
- Mitis junctional epidermolysis bullosa (also known as "Nonlethal junctional epidermolysis bullosa") is a skin condition characterized by scalp and nail lesions, also associated with periorificial nonhealing erosions.[1]: 599 Mitis junctional epidermolysis bullosa is most commonly seen in children between the ages of 4 and 10 years old.[1]: 600
- Cicatricial junctional epidermolysis bullosa is a skin condition characterized by blisters that heal with scarring.[2]: 557 It was characterized in 1985.[5]
Pathophysiology
α6β4 integrin is a transmembrane protein found in hemidesmosomes. As a heterodimer molecule containing two polypeptide chains its extracellular domain enters the basal lamina and interacts with type IV collagen suprastructure containing laminins (laminin-5), entactin/nidongen or the perlecan. on the extracellular surface of the hemidesmosome, laminin-5 molecules form threadlike anchoring filaments that extend from the integrin molecules to the structure of the basement membrane of epithelial adhesion. Mutation of the genes encoding laminin-5 chains results in junctional epidermolysis bullosa.[6]
See also
References
- ^ a b c d e Freedberg, et al. (2003). Fitzpatrick's Dermatology in General Medicine. (6th ed.). McGraw-Hill. ISBN 0-07-138076-0.
- ^ a b c d James, William; Berger, Timothy; Elston, Dirk (2005). Andrews' Diseases of the Skin: Clinical Dermatology. (10th ed.). Saunders. ISBN 0-7216-2921-0.
- ^ Online Mendelian Inheritance in Man (OMIM): 226730
- ^ Rapini, Ronald P.; Bolognia, Jean L.; Jorizzo, Joseph L. (2007). Dermatology: 2-Volume Set. St. Louis: Mosby. ISBN 1-4160-2999-0.
- ^ Haber RM, Hanna W, Ramsay CA, Boxall LB (May 1985). "Cicatricial junctional epidermolysis bullosa". J. Am. Acad. Dermatol. 12 (5 Pt 1): 836–44. doi:10.1016/S0190-9622(85)70105-3. PMID 4008687.
- ^ Histology A Text And Atlas by Michael H. Ross