Eczema pathophysiology: Difference between revisions
Jump to navigation
Jump to search
| Line 18: | Line 18: | ||
** This hypothesis suggests that an impairment of the [[skin]] barrier should occur first before the onset of [[atopic dermatitis]]. | ** This hypothesis suggests that an impairment of the [[skin]] barrier should occur first before the onset of [[atopic dermatitis]]. | ||
** This involves the [[down-regulation]] of [[filaggrin genes]] (''[[FLG]]'') responsible for maintenance of the proper function of [[skin]] barrier.<ref name="pmid26761930">{{cite journal| author=Silverberg NB, Silverberg JI| title=Inside out or outside in: does atopic dermatitis disrupt barrier function or does disruption of barrier function trigger atopic dermatitis? | journal=Cutis | year= 2015 | volume= 96 | issue= 6 | pages= 359-61 | pmid=26761930 | doi= | pmc= | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=26761930 }} </ref> <ref name="pmid25282559">{{cite journal| author=Leung DY, Guttman-Yassky E| title=Deciphering the complexities of atopic dermatitis: shifting paradigms in treatment approaches. | journal=J Allergy Clin Immunol | year= 2014 | volume= 134 | issue= 4 | pages= 769-79 | pmid=25282559 | doi=10.1016/j.jaci.2014.08.008 | pmc=4186710 | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=25282559 }} </ref> | ** This involves the [[down-regulation]] of [[filaggrin genes]] (''[[FLG]]'') responsible for maintenance of the proper function of [[skin]] barrier.<ref name="pmid26761930">{{cite journal| author=Silverberg NB, Silverberg JI| title=Inside out or outside in: does atopic dermatitis disrupt barrier function or does disruption of barrier function trigger atopic dermatitis? | journal=Cutis | year= 2015 | volume= 96 | issue= 6 | pages= 359-61 | pmid=26761930 | doi= | pmc= | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=26761930 }} </ref> <ref name="pmid25282559">{{cite journal| author=Leung DY, Guttman-Yassky E| title=Deciphering the complexities of atopic dermatitis: shifting paradigms in treatment approaches. | journal=J Allergy Clin Immunol | year= 2014 | volume= 134 | issue= 4 | pages= 769-79 | pmid=25282559 | doi=10.1016/j.jaci.2014.08.008 | pmc=4186710 | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=25282559 }} </ref> | ||
===Genetic Inheritance=== | |||
*There are 34 [[genetic loci]] which are thought to be associated with [[eczema]]. | |||
*These regions contain several [[genes]] which have important [immunological]] functions, such as [[T-cell]] activation, [[type-2 helper cell]] differentiation, and [[innate immunity]]. <ref name="pmid26482879">{{cite journal| author=Paternoster L, Standl M, Waage J, Baurecht H, Hotze M, Strachan DP | display-authors=etal| title=Multi-ancestry genome-wide association study of 21,000 cases and 95,000 controls identifies new risk loci for atopic dermatitis. | journal=Nat Genet | year= 2015 | volume= 47 | issue= 12 | pages= 1449-1456 | pmid=26482879 | doi=10.1038/ng.3424 | pmc=4753676 | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=26482879 }} </ref> <ref name="pmid23886662">{{cite journal| author=Weidinger S, Willis-Owen SA, Kamatani Y, Baurecht H, Morar N, Liang L | display-authors=etal| title=A genome-wide association study of atopic dermatitis identifies loci with overlapping effects on asthma and psoriasis. | journal=Hum Mol Genet | year= 2013 | volume= 22 | issue= 23 | pages= 4841-56 | pmid=23886662 | doi=10.1093/hmg/ddt317 | pmc=3820131 | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=23886662 }} </ref><ref name="pmid32325630">{{cite journal| author=Martin MJ, Estravís M, García-Sánchez A, Dávila I, Isidoro-García M, Sanz C| title=Genetics and Epigenetics of Atopic Dermatitis: An Updated Systematic Review. | journal=Genes (Basel) | year= 2020 | volume= 11 | issue= 4 | pages= | pmid=32325630 | doi=10.3390/genes11040442 | pmc=7231115 | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=32325630 }} </ref> | |||
==References== | ==References== | ||
Revision as of 14:58, 21 June 2022
|
Eczema Microchapters |
|
Diagnosis |
|---|
|
Treatment |
|
Case Studies |
|
Eczema On the Web |
|
American Roentgen Ray Society Images of Eczema |
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Edzel Lorraine Co, D.M.D., M.D.
Overview
The mechanism of disease of eczema involves a complex interplay of abnormalities of skin microbiomes, a dysfunction in the epidermal barrier, and an immune dysregulation. [1] There are two main theories on the existence of atopic dermatitis, also known as atopic eczema - the inside-out hypothesis, and the outside-in hypothesis.
Pathophysiology
- Affected skin involves the uptake of antigens and allergensby the epidermal dendritic cells, dermal dendritic cells, and Langerhan cells.
- Sensory nerves are activated by the released cytokines interleukins 4,13 and 31 (IL-4, IL-13, and IL-31), which are responsible for the pruritic sensation.
- As the event becomes chronic, an increased expression of keratinocyte and Th-cell-derived cytokines is achieved, with more pruritogens contributing to itch sensation. [1]
- There are two main theories on the existence of atopic dermatitis, also known as atopic eczema - the inside-out hypothesis, and the outside-in hypothesis.[2]
- Inside-out hypothesis
- This hypothesis denotes that some allergic triggers weaken the skin barrier that leads to more introduction of allergens to the area, causing more inflammatory reaction.[2]
- Outside-in hypothesis
- This hypothesis suggests that an impairment of the skin barrier should occur first before the onset of atopic dermatitis.
- This involves the down-regulation of filaggrin genes (FLG) responsible for maintenance of the proper function of skin barrier.[2] [3]
Genetic Inheritance
- There are 34 genetic loci which are thought to be associated with eczema.
- These regions contain several genes which have important [immunological]] functions, such as T-cell activation, type-2 helper cell differentiation, and innate immunity. [4] [5][6]
References
- ↑ 1.0 1.1 Feld M, Garcia R, Buddenkotte J, Katayama S, Lewis K, Muirhead G; et al. (2016). "The pruritus- and TH2-associated cytokine IL-31 promotes growth of sensory nerves". J Allergy Clin Immunol. 138 (2): 500–508.e24. doi:10.1016/j.jaci.2016.02.020. PMID 27212086.
- ↑ 2.0 2.1 2.2 Silverberg NB, Silverberg JI (2015). "Inside out or outside in: does atopic dermatitis disrupt barrier function or does disruption of barrier function trigger atopic dermatitis?". Cutis. 96 (6): 359–61. PMID 26761930.
- ↑ Leung DY, Guttman-Yassky E (2014). "Deciphering the complexities of atopic dermatitis: shifting paradigms in treatment approaches". J Allergy Clin Immunol. 134 (4): 769–79. doi:10.1016/j.jaci.2014.08.008. PMC 4186710. PMID 25282559.
- ↑ Paternoster L, Standl M, Waage J, Baurecht H, Hotze M, Strachan DP; et al. (2015). "Multi-ancestry genome-wide association study of 21,000 cases and 95,000 controls identifies new risk loci for atopic dermatitis". Nat Genet. 47 (12): 1449–1456. doi:10.1038/ng.3424. PMC 4753676. PMID 26482879.
- ↑ Weidinger S, Willis-Owen SA, Kamatani Y, Baurecht H, Morar N, Liang L; et al. (2013). "A genome-wide association study of atopic dermatitis identifies loci with overlapping effects on asthma and psoriasis". Hum Mol Genet. 22 (23): 4841–56. doi:10.1093/hmg/ddt317. PMC 3820131. PMID 23886662.
- ↑ Martin MJ, Estravís M, García-Sánchez A, Dávila I, Isidoro-García M, Sanz C (2020). "Genetics and Epigenetics of Atopic Dermatitis: An Updated Systematic Review". Genes (Basel). 11 (4). doi:10.3390/genes11040442. PMC 7231115 Check
|pmc=value (help). PMID 32325630 Check|pmid=value (help).