Editing Lichen simplex chronicus

{{Short description|Human skin disorder}}
{{Infobox medical condition (new)
| name            = Lichen simplex chronicus
| synonyms        = Neurodermatitis<ref name=Andrew2020/>
| image           = Lichen simplex chronicus - very low mag.jpg
| caption         = [[Micrograph]] of lichen simplex chronicus. [[H&E stain]].
| pronounce       = 
| field           = 
| symptoms        = [[lichenification|Thick]] leathery skin, exaggerated skin markings, [[papule|small bumps]], patches, [[excoriation|scratch marks]], scale<ref name=Andrew2020/>
| complications   = 
| onset           = Gradual<ref name=Andrew2020/>
| duration        = 
| types           = 
| causes          = Excessive rubbing and [[Scratch reflex|scratching]]<ref name=Andrew2020/>
| risks           = 
| diagnosis       = 
| differential    = 
| prevention      = 
| treatment       = 
| medication      = 
| prognosis       = 
| frequency       = 
| deaths          = 
}}
'''Lichen simplex chronicus''' ('''LSC''') is [[lichenification|thick]] leathery skin with exaggerated skin markings caused by sudden [[pruritus|itching]] and excessive rubbing and [[Scratch reflex|scratching]].<ref name=Andrew2020>{{cite book |last1=James |first1=William D. |last2=Elston |first2=Dirk |last3=Treat |first3=James R. |last4=Rosenbach |first4=Misha A. |last5=Neuhaus |first5=Isaac |title=Andrews' Diseases of the Skin: Clinical Dermatology |date=2020 |publisher=Elsevier |isbn=978-0-323-54753-6 |pages=53–54|edition=13th |chapter-url=https://books.google.com/books?id=UEaEDwAAQBAJ&dq=Lichen+simplex&pg=PA53 |language=en |chapter=4. Pruritus and neurocutaneous dermatoses}}</ref> It generally results in [[papule|small bumps]], patches, [[excoriation|scratch marks]] and scale.<ref name=Andrew2020/> It typically affects the neck, scalp, upper eyelids, ears, palms, soles, ankles, wrists, genital areas and bottom.<ref name=Andrew2020/> It often develops gradually and the scratching becomes a habit.<ref name=Andrew2020/>

== Signs and symptoms ==
People burdened with LSC report [[Itch|pruritus]], followed by uncontrollable scratching of the same body region, excessively.<ref name=":0">{{Cite journal|last=Lynch|first=Peter J.|date=2004-01-01|title=Lichen simplex chronicus (atopic/neurodermatitis) of the anogenital region|journal=Dermatologic Therapy|volume=17|issue=1|pages=8–19|issn=1396-0296|pmid=14756886|doi=10.1111/j.1396-0296.2004.04002.x|s2cid=22038447|doi-access=free}}</ref> Most common sites of LSC are the sides of the neck, the scalp, ankles, vulva, pubis, scrotum, and extensor sides of the forearms.<ref name=":1" /> However, due to the [[Social stigma|stigma]] associated with chronic scratching, some patients will not admit to chronic rubbing or abrasion. The skin may become thickened and hyperpigmented (lichenified) as a direct result of chronic excoriation.<ref name=":1" /> Typically this period of increased scratching is associated with stressors.

== Causes ==
This is a skin disorder characterized by a self-perpetuating scratch-itch cycle:<ref>{{Cite journal|last1=Lee|first1=Michael R.|last2=Shumack|first2=Stephen|date=2005-11-01|title=Prurigo nodularis: a review|journal=The Australasian Journal of Dermatology|volume=46|issue=4|pages=211–218; quiz 219–220|doi=10.1111/j.1440-0960.2005.00187.x|issn=0004-8380|pmid=16197418|s2cid=30087432}}</ref> 
*It may begin with something that rubs, irritates, or scratches the skin, such as clothing.
*This causes the person to rub or scratch the affected area. Constant scratching causes the skin to thicken.
*The thickened skin itches, causing more scratching, causing more thickening.
*Affected area may spread rapidly through the rest of the body.
Many hypothesize LSC has a psychosomatic origin.<ref name=":1">{{Cite journal|last1=Lotti|first1=Torello|last2=Buggiani|first2=Gionata|last3=Prignano|first3=Francesca|date=2008-01-01|title=Prurigo nodularis and lichen simplex chronicus|journal=Dermatologic Therapy|language=en|volume=21|issue=1|pages=42–46|doi=10.1111/j.1529-8019.2008.00168.x|pmid=18318884|s2cid=41222102|issn=1529-8019}}</ref> Those predisposed to itch as a response to emotional tensions may be more susceptible to the itch-scratch cycle. It may also be associated with nervousness, [[anxiety]], [[clinical depression|depression]], and other psychological disorders.<ref>{{Cite journal|last1=Konuk|first1=Numan|last2=Koca|first2=Rafet|last3=Atik|first3=Levent|last4=Muhtar|first4=Sennur|last5=Atasoy|first5=Nuray|last6=Bostanci|first6=Bora|date=2007-05-01|title=Psychopathology, depression and dissociative experiences in patients with lichen simplex chronicus|url=http://www.ghpjournal.com/article/S0163-8343(07)00007-2/abstract|journal=General Hospital Psychiatry|language=en|volume=29|issue=3|pages=232–235|doi=10.1016/j.genhosppsych.2007.01.006|pmid=17484940|issn=0163-8343|url-access=subscription}}</ref><ref>{{Cite journal|last1=Krishnan|first1=Anjeli|last2=Koo|first2=John|date=2005-07-01|title=Psyche, opioids, and itch: therapeutic consequences|journal=Dermatologic Therapy|volume=18|issue=4|pages=314–322|doi=10.1111/j.1529-8019.2005.00038.x|issn=1396-0296|pmid=16297003|s2cid=25983822|doi-access=free}}</ref> Many people with LSC are aware of the scratching they do during the day, but they might not be aware of the scratching they do in their sleep.<ref name=":0" /> LSC is also associated with [[atopy]], or [[atopic dermatitis]] (eczema) and an increase of histamine levels.<ref name=":0" />

== Diagnosis ==
LSC is typically diagnosed by careful observation and history taking.<ref name=":1" /> It is easily recognized (see ''signs and symptoms'', and ''gallery'').<ref name=":0" /> Biopsies are sometimes necessary to confirm the diagnosis and differentiate it from other similar appearing lesions.

== Treatment ==
Treatment is aimed at reducing itching and minimizing existing lesions because rubbing and scratching exacerbate LSC. The itching and inflammation may be treated with a lotion or [[steroid]] cream (such as [[Kenalog|triamcinolone]] or [[Betamethasone]]) applied to the affected area of the skin.<ref>{{Cite journal|last1=Yosipovitch|first1=Gil|last2=Bernhard|first2=Jeffrey D.|date=2013-04-25|title=Chronic Pruritus|journal=New England Journal of Medicine|volume=368|issue=17|pages=1625–1634|doi=10.1056/NEJMcp1208814|issn=0028-4793|pmid=23614588|s2cid=1912215 }}</ref> Night-time scratching can be reduced with sedatives and antihistamines.<ref name=":0" /> [[Doxepin]] is often prescribed, as it offers both antihistamine properties and is also effective at reducing the (itch scratch cycle) associated with the obsessive [[psychosomatic]] behavioral symptoms.

===Gallery===
<gallery>
Image:Lichen_simplex_chronicus_1.jpg
Image:Lichen_simplex_chronicus_2.jpg
Image:Lichen_simplex_chronicus_3.jpg
Image:Lichen_simplex_chronicus_4.jpg
</gallery>

== See also ==
* [[List of cutaneous conditions]]

== References ==
{{reflist}}

== External links ==
{{Medical resources
|  DiseasesDB      = 31441  
|  ICD10           = {{ICD10|L|28|0|l|20}}   
|  ICD9            = {{ICD9|698.3}}  
|  ICDO            =  
|  OMIM            =  
|  MedlinePlus     = 000872  
|  eMedicineSubj   = derm  
|  eMedicineTopic  = 236  
|  MeshID          = D009450 
}}
{{Diseases of the skin and appendages by morphology}}
{{Diseases of the skin and subcutaneous tissue}}

[[Category:Pruritic skin conditions]]