"Butterfly child" is the colloquial name for a child born with the disease, as their skin is seen to be as delicate and fragile as the wings of a butterfly.[3]
Signs and symptomsedit
The deficiency in anchoring fibrils impairs the adherence between the epidermis and the underlying dermis. The skin of DEB patients is thus highly susceptible to severe blistering.[citation needed] Collagen VII is also associated with the epithelium of the esophageal lining, and DEB patients may have chronic scarring, webbing, and obstruction of the esophagus. Affected individuals are often severely malnourished due to trauma to the oral and esophageal mucosa and require feeding tubes for nutrition. They also have iron-deficiency anemia of uncertain origin, which leads to chronic fatigue.[citation needed]
Open wounds on the skin heal slowly or not at all, often scarring extensively, and are particularly susceptible to infection. Many individuals bathe in a bleach and water mixture to fight off these infections.[citation needed] The chronic inflammation leads to errors in the DNA of the affected skin cells, which in turn causes squamous cell carcinoma (SCC). The majority of these patients die before the age of 30, either of SCC or complications related to DEB.[citation needed]
The chronic inflammatory state seen in recessive dystrophic epidermolysis bullosa (RDEB) may cause small fiber peripheral neuropathy (SFN);[4] RDEB patients have reported the sensation of pain in line with neuropathic pain qualities.[5]
Causesedit
DEB is caused by genetic defects (or mutations) within the human COL7A1 gene encoding the protein type VII collagen (collagen VII).[6] DEB-causing mutations can be either dominant or recessive.[citation needed] Most families with family members with this condition have distinct mutations.[7]
Collagen VII is a very large molecule (300 kDa) that dimerizes to form a semicircular looping structure: the anchoring fibril. Anchoring fibrils are thought to form a structural link between the epidermal basement membrane and the fibrillar collagens in the upper dermis.[citation needed]
Pathophysiologyedit
In the absence of mutations of the COL7A1 gene, an autoimmune response against type VII collagen can result in an acquired form of epidermolysis bullosa called epidermolysis bullosa acquisita.[8]
There exist other types of inherited epidermolysis bullosa, junctional epidermolysis bullosa and epidermolysis bullosa simplex, which are not related to type VII collagen deficiency. These arise from mutations in the genes encoding other proteins of the epidermis or the basement membrane at the junction between the epidermis and the dermis.[9]
Also known as "Hallopeau–Siemens variant of epidermolysis bullosa"[12] and "Hallopeau–Siemens disease",[13] this variant results from mutations in the gene encoding type VII collagen, COL7A1, characterized by debilitating oral lesions that produce pain, scarring, and microstomia.[14][11] It is named for François Henri Hallopeau and Hermann Werner Siemens.
In May 2023, the FDA approved Vyjuvek for the treatment of wounds in people with dystrophic epidermolysis bullosa with mutation(s) in the collagen type VII alpha 1 chain (COL7A1) gene.[15][16]
^Reference, Genetics Home. "dystrophic epidermolysis bullosa". Genetics Home Reference. Retrieved 2017-04-03.
^Bardhan, Ajoy; Bruckner-Tuderman, Leena; Chapple, Iain L. C.; Fine, Jo-David; Harper, Natasha; Has, Cristina; Magin, Thomas M.; Marinkovich, M. Peter; Marshall, John F.; McGrath, John A.; Mellerio, Jemima E. (2020-09-24). "Epidermolysis bullosa". Nature Reviews Disease Primers. 6 (1): 78. doi:10.1038/s41572-020-0210-0. ISSN 2056-676X. PMID 32973163. S2CID 221861310.
^Pittman, Taylor (2015-04-21). "'Butterfly Child' With Rare, Painful Condition Displays Strength That Will Blow You Away". Huffington Post. Retrieved 2017-07-14.
^[1], Recessive dystrophic epidermolysis bullosa results in painful small fibre neuropathy.
^Varki, R.; Sadowski, S.; Uitto, J.; Pfendner, E. (March 2007). "Epidermolysis bullosa. II. Type VII collagen mutations and phenotype–genotype correlations in the dystrophic subtypes". Journal of Medical Genetics. 44 (3): 181–92. doi:10.1136/jmg.2006.045302. PMC2598021. PMID 16971478.
^Csikós, M.; Szőcs, H. I.; Lászik, A.; Mecklenbeck, S.; Horváth, A.; Kárpáti, S.; Bruckner-Tuderman, L. (May 2005). "High frequency of the 425A→G splice-site mutation and novel mutations of the COL7A1 gene in central Europe: significance for future mutation detection strategies in dystrophic epidermolysis bullosa". British Journal of Dermatology. 152 (5): 879–886. doi:10.1111/j.1365-2133.2005.06542.x. PMID 15888141. S2CID 44394902.
^Mihai, Sidonia; Sitaru, Cassian (May–June 2007). "Immunopathology and molecular diagnosis of autoimmune bullous diseases". Journal of Cellular and Molecular Medicine. 11 (3): 462–481. doi:10.1111/j.1582-4934.2007.00033.x. PMC3922353. PMID 17521373.
^Fine, Jo-David; Eady, Robin A. J.; Bauer, Eugene A.; Bauer, Johann W.; Bruckner-Tuderman, Leena; Heagerty, Adrian; Hintner, Helmut; Hovnanian, Alain; Jonkman, Marcel F.; Leigh, Irene; McGrath, John A.; Mellerio, Jemima E.; Murrell, Dedee F.; Shimizu, Hiroshi; Uitto, Jouni; Vahlquist, Anders; Woodley, David; Zambruno, Giovanna (2008). "The classification of inherited epidermolysis bullosa (EB): Report of the Third International Consensus Meeting on Diagnosis and Classification of EB". Journal of the American Academy of Dermatology. 58 (6): 931–950. doi:10.1016/j.jaad.2008.02.004. PMID 18374450.
^Commissioner, Office of the (2023-05-19). "FDA Approves First Topical Gene Therapy for Treatment of Wounds in Patients with Dystrophic Epidermolysis Bullosa". FDA. Retrieved 2023-06-01.
^Research, Center for Biologics Evaluation and (2023-05-19). "VYJUVEK". FDA.
Sourcesedit
Freedberg, Irwin M.; Eisen, Arthur Z.; Wolff, Klauss; Austen, K. Frank; Goldsmith, Lowell A.; Katz, Stephen I., eds. (2003). Fitzpatrick's Dermatology in General Medicine (6th ed.). McGraw-Hill. ISBN 978-0-07-138076-8.
James, William; Berger, Timothy; Elston, Dirk (2005). Andrews' Diseases of the Skin: Clinical Dermatology (10th ed.). Saunders. ISBN 978-0-7216-2921-6.
Rapini, Ronald P.; Bolognia, Jean L.; Jorizzo, Joseph L. (2007). Dermatology: 2-Volume Set. St. Louis: Mosby. ISBN 978-1-4160-2999-1.