{{short description|Inflammation due to damage of skin capillaries when blood perfuses into nearby tissue}} {{Infobox medical condition (new) | name = Chilblains | synonyms = Pernio, perniones, kibes, perniosis<ref name="Andrews">{{cite book |last1=James |first1=William D. |last2=Elston |first2=Dirk M. |last3=Treat |first3=James R. |last4=Rosenbach |first4=Misha A. |last5=Neuhaus |first5=Isaac M. |title=Andrews' Diseases of the Skin |date=2020 |publisher=Elsevier |isbn=978-0-323-54753-6 |edition=13th |chapter=Dermatoses Resulting From Physical Factors|pages=18–45}}</ref> | pronounce = {{IPAc-en|ˈ|tʃ|ɪ|l|b|l|eɪ|n|z}} | image = Wintertenen.jpg | caption = Toes inflamed by chilblains | field = Internal medicine, podiatry | symptoms = | complications = | onset = | duration = | types = | causes = | risks = | diagnosis = | differential = | prevention = | treatment = | medication = | prognosis = | frequency = | deaths = }}
'''Chilblains''', also known as '''pernio''', is a medical condition in which damage occurs to capillary beds in the skin, most often in the hands or feet, when blood perfuses into the nearby tissue, resulting in redness, itching, inflammation, and possibly blisters.<ref>[https://www.cdc.gov/niosh/topics/coldstress/ Cold Stress: Chilblains]. National Institute for Occupational Safety and Health. Retrieved January 6, 2009.</ref>
It occurs most frequently when predisposed individuals, predominantly women,<ref name="What Are COVID Toes? A Case Study">{{cite journal |last1=Beuscher |first1=Tara L. |last2=Andrews |first2=Sarah E. |title=What Are COVID Toes? A Case Study |journal=Journal of Wound, Ostomy & Continence Nursing |date=November 2020 |volume=47 |issue=6 |pages=619–621 |doi=10.1097/WON.0000000000000711|pmid=33201148 |s2cid=226988942 }}</ref> are exposed to cold and humidity. Ulcerated chilblains are referred to as '''kibes'''. Temperature-related chilblains can be prevented by keeping the feet and hands warm in cold weather and avoiding exposing these areas to extreme temperature changes. Once the diagnosis of chilblains is made, first-line treatment includes avoiding cold, damp environments and wearing gloves and warm socks.<ref name="What Are COVID Toes? A Case Study"/>
Chilblains can be idiopathic (spontaneous and unrelated to another disease), but similar symptoms may also be a manifestation of another serious medical condition that must be investigated. Related medical conditions include Raynaud syndrome, erythromelalgia, frostbite, and trench foot, as well as connective tissue diseases such as lupus or vasculitis. In infants affected by Aicardi–Goutières syndrome (a rare inherited condition which affects the nervous system), chilblain-like symptoms occur together with severe neurologic disturbances and unexplained fevers.
== Signs and symptoms ==
thumb|upright=1.3|Chilblains of the feet, caused by excessive exposure to cold and humidity Symptoms of chillblains include dermatitis in toes, fingers, earlobes, nose and other extremities. This may present as:
* Burning and itching sensations * Throbbing pain * Skin discoloration (red to dark blue) with erythema (blanchable redness) * Blistering of affected area * Ulceration (in severe cases only)
Chilblains caused by exposure to cold and humidity usually heal within 7–14 days.
== Treatment == Nifedipine and amlodipine, which are vasodilators in the class of drugs known as calcium channel blockers, may be used as treatments.<ref>{{cite journal |last1=Rustin |first1=M.H.A. |last2=Newton |first2=Julia A. |last3=Smith |first3=N.P. |last4=Dowd |first4=Pauline M. |title=The treatment of chilblains with nifedipine: the results of a pilot study, a double-blind placebo-controlled randomized study and a long-term open trial |journal=British Journal of Dermatology |volume=120 |issue=2 |pages=267–75 |year=2006 |pmid=2647123 |doi=10.1111/j.1365-2133.1989.tb07792.x|s2cid=13230013 }}</ref> Vasodilation may reduce pain, facilitate healing, and prevent recurrences.<ref>{{cite journal |last1=Simon |first1=T. D. |last2=Soep |first2=JB |last3=Hollister |first3=JR |title=Pernio in Pediatrics |journal=Pediatrics |volume=116 |issue=3 |pages=e472–5 |year=2005 |pmid=16140694 |doi=10.1542/peds.2004-2681|doi-access= |s2cid=2091725 }}</ref> Vasodilators are typically available in an oral pill but can be compounded into a topical formula. Diltiazem, another vasodilator, is also sometimes used.<ref>{{cite journal |last1=Patra |first1=AK |last2=Das |first2=AL |last3=Ramadasan |first3=P |title=Diltiazem vs. nifedipine in chilblains: A clinical trial |pmid=17642888 |date=2003 |pages=209–11 |issue=3 |volume=69 |journal=Indian Journal of Dermatology, Venereology and Leprology |url=http://www.ijdvl.com/text.asp?2003/69/3/209/999}}</ref>
== Etymology == The word is a compound of Modern English ''chill'' 'cold' and the archaic word ''blain'' (now used only in the word in question), meaning 'swelling', 'blister' or 'sore' and derived from Old English ''bleġen'', ''bleġene'', having the same meaning.<ref>https://en.wiktionary.org/wiki/chilblain Retrieved at 8.45 on Wednesday 20/12/23.</ref>
==Alternative remedies== The medieval ''Bald's Leechbook'' recommended treating chilblains with a mixture of eggs, wine, and fennel root.<ref>Robert Lacey and Danny Danziger August: ''The Year 1000: What Life Was Like at the Turn of the First Millennium'' Little, Brown, 2000 {{ISBN|0316511579}}{{page needed|date=December 2010}}</ref> A modern-day home remedy is to put garlic on the chilblains.<ref>{{cite web|url=http://www.saludplena.com/index.php/remedios-caseros-para-sabanones/|title=Remedios caseros para sabañones|work=saludplena.com|language=es|access-date=29 December 2016}}</ref> Other herbal remedies supposed to be vasodilating, rubifacient, and warming, have been recommended.
== COVID-19 == Chilblain-like symptoms have also been linked to COVID-19.<ref name="Wollina2020">{{cite journal|vauthors=Wollina U, Karadağ AS, Rowland-Payne C, Chiriac A, Lotti T|date=2020|title=Cutaneous signs in COVID-19 Patients: a review|journal=Dermatologic Therapy|volume=33|issue=5|article-number=e13549|doi=10.1111/dth.13549|pmc=7273098|pmid=32390279|doi-access=free}}</ref><ref name="Young2020">{{cite journal|vauthors=Young S, Fernandez AP|date=2020|title=Skin manifestations of COVID-19|journal=Cleveland Clinic Journal of Medicine|doi=10.3949/ccjm.87a.ccc031|pmid=32409442|doi-access=free}}</ref><ref name="Kaya2020">{{cite journal|vauthors=Kaya G, Kaya A, Saurat JH|date=June 2020|title=Clinical and histopathological features and potential pathological mechanisms of skin lesions in COVID-19: review of the literature|journal=Dermatopathology|volume=7|issue=1|pages=3–16|doi=10.3390/dermatopathology7010002|pmc=7583593|pmid=32608380|quote=In acral chilblain-like lesions, a diffuse dense lymphoid infiltrate of the superficial and deep dermis, as well as hypodermis, with a prevalent perivascular pattern and signs of endothelial activation, are observed.|doi-access=free}}</ref> '''COVID toes''', as they are commonly known,<ref name="Massey2020">{{cite journal|vauthors=Massey PR, Jones KM|date=May 2020|title=Going viral: A brief history of chilblain-like skin lesions ("COVID toes") amidst the COVID-19 pandemic|journal=Seminars in Oncology|volume=47|issue=5|pages=330–334|doi=10.1053/j.seminoncol.2020.05.012|pmc=7245293|pmid=32736881|doi-access=free}}</ref><ref name="Bristow2020">{{cite journal|vauthors=Bristow IR, Borthwick AM|date=June 2020|title=The mystery of the COVID toes – turning evidence-based medicine on its head|journal=Journal of Foot and Ankle Research|volume=13|issue=1|page=38|doi=10.1186/s13047-020-00408-w|pmc=7309429|pmid=32576291|doi-access=free}}</ref><ref name=":0">{{Cite journal|last1=Rocha|first1=Kelvin Oliveira|last2=Zanuncio|first2=Virgínia Vinha|last3=Freitas|first3=Brunnella Alcântara Chagas de|last4=Lima|first4=Luciana Moreira|title="COVID toes": A meta-analysis of case and observational studies on clinical, histopathological, and laboratory findings|journal=Pediatric Dermatology|year=2021|volume=38|issue=5|pages=1143–1149|language=en|doi=10.1111/pde.14805|pmid=34515379|pmc=8646534|issn=1525-1470|doi-access=free}}</ref> have mostly been reported in older children and adolescents,<ref name="Walker2020">{{cite journal|vauthors=Walker DM, Tolentino VR|date=June 2020|title=COVID-19: The impact on pediatric emergency care|url=https://www.ebmedicine.net/topics/infectious-disease/COVID-19-Peds|journal=Pediatric Emergency Medicine Practice|volume=17|issue=Suppl 6-1|pages=1–27|pmid=32496723}}</ref><ref name=":0" /> who often have not had other symptoms of COVID-19.<ref name="Ladha2020">{{cite journal|vauthors=Ladha MA, Luca N, Constantinescu C, Naert K, Ramien ML|date=August 2020|title=Approach to chilblains during the COVID-19 pandemic|journal=Journal of Cutaneous Medicine and Surgery|volume=24|issue=5|pages=504–517|doi=10.1177/1203475420937978|pmid=32741218|doi-access=free}}</ref> The symptoms are usually mild and disappear without treatment.<ref name="Walker2020" /><ref name=":0" /> Their cause is debated: it is uncertain whether COVID toes are a delayed consequence of the viral infection itself or are, at least partially, connected to environmental factors during the COVID-19 pandemic.<ref name="Massey2020" /><ref name="Bristow2020" /><ref>[https://www.mayoclinic.org/diseases-conditions/coronavirus/expert-answers/coronavirus-unusual-symptoms/faq-20487367 Unusual coronavirus (COVID-19) symptoms: What are they?]</ref> They may share some of the microscopic features of chilblains caused by lupus.<ref name="Ladha2020" /> It has been suggested that in the absence of exposure to cold and damp, COVID-19 should be considered as a possible cause of chilblains.<ref name="Ladha2020" />
In a study at the dermatology department of Saint-Louis Hospital in Paris, researchers found that most of their study participants carried high levels of autoantibodies, proteins generated by the immune system that inadvertently attack the body's own tissues. Compared with healthy individuals, the participants showed high activity of proteins called type 1 interferons, which switch on pathogen-fighting genes in immune cells.<ref>{{Cite web|author1=Nicoletta Lanese|date=2021-10-07|title=We might finally know what causes 'COVID toes'|url=https://www.livescience.com/mystery-of-covid-toes-solved|access-date=2022-01-08|website=livescience.com|language=en}}</ref>
== See also == * Equestrian perniosis * Erythrocyanosis crurum * Raynaud's disease
== References == {{Reflist}}
== External links == {{Wiktionary}} {{Commons category}} * {{DermAtlas|1683395337}} * [https://www.cdc.gov/niosh/topics/coldstress/ Cold stress], National Institute for Occupational Safety and Health
{{Medical resources | DiseasesDB=31219 | ICD10={{ICD10|T|69|1|t|66}} | ICD9={{ICD9|991.5}} | ICDO= | OMIM= | MedlinePlus= | eMedicineSubj=derm | eMedicineTopic=322 | MeshID=D002647 }} {{Consequences of external causes|state=collapsed}} {{Authority control}}
Category:Effects of external causes Category:Foot diseases Category:Skin conditions resulting from physical factors