Alopecia areata

Alopecia areata
Other namesAlopecia Celsi, vitiligo capitis, Jonston's alopecia[1]
Alopecia areata seen on the back of the scalp
Pronunciation
SpecialtyDermatology Immunology[6]
SymptomsAreas of hair loss, usually on the scalp[7]
Usual onsetChildhood[7]
CausesAutoimmune[7]
Risk factorsFamily history, female sex, rheumatoid arthritis, type 1 diabetes, celiac disease[7][8][9]
Differential diagnosisTrichotillomania, alopecia mucinosa, postpartum alopecia[1]
TreatmentSunscreen, head coverings to protect from sun and cold[7]
Medicationtopical minoxidil[10] and triamcinolone injections[11]
PrognosisDoes not affect life expectancy[7][1]
Frequency~2% (US)[7]

Alopecia areata, also known as spot baldness, is a condition in which hair is lost from some or all areas of the body.[12][1] It often results in a few bald spots on the scalp, each about the size of a coin.[7] Psychological stress and illness are possible factors in bringing on alopecia areata in individuals at risk, but in most cases there is no obvious trigger.[7] People are generally otherwise healthy.[7] In a few cases, all the hair on the scalp is lost (alopecia totalis), or all body hair is lost (alopecia universalis). Hair loss can be permanent, or temporary.[7][1]

Alopecia areata is believed to be an autoimmune disease resulting from a breach in the immune privilege of the hair follicles.[12][13] Risk factors include a family history of the condition.[7] Among identical twins, if one is affected, the other has about a 50% chance of also being affected.[7] The underlying mechanism involves failure by the body to recognize its own cells, with subsequent immune-mediated destruction of the hair follicle.[7]

No cure for the condition is known.[7] Some treatments, particularly triamcinolone injections and 5% minoxidil topical creams,[11][10] are effective in speeding hair regrowth.[7][1] Sunscreen, head coverings to protect from cold and sun, and glasses, if the eyelashes are missing, are also recommended.[7] In more than 50% of cases of sudden-onset localized "patchy" disease, hair regrows within a year.[14][15][7] In patients with only one or two patches, this one-year recovery will occur in up to 80%.[16][17] However, many people will have more than one episode over the course of a lifetime.[15] In many patients, hair loss and regrowth occurs simultaneously over the course of several years.[7] Among those in whom all body hair is lost, fewer than 10% recover.[18]

About 0.15% of people are affected at any one time, and 2% of people are affected at some point in time.[7][18] Onset is usually in childhood.[7] Females are affected at higher rates than males.[9]

  1. ^ a b c d e f "Alopecia Areata - NORD (National Organization for Rare Disorders)". NORD (National Organization for Rare Disorders). 2004. Archived from the original on 21 February 2017. Retrieved 10 July 2017.
  2. ^ "alopecia". The Chambers Dictionary (9th ed.). Chambers. 2003. ISBN 0-550-10105-5.
  3. ^ "alopecia". Collins English Dictionary (13th ed.). HarperCollins. 2018. ISBN 978-0-008-28437-4.
  4. ^ "Definition of alopecia | Dictionary.com". www.dictionary.com. Archived from the original on 28 March 2022. Retrieved 14 February 2022.
  5. ^ "alopecia". Merriam-Webster.com Dictionary. Merriam-Webster. Retrieved 25 March 2022.
  6. ^ "Alopecia Areata". National Institute of Arthritis and Musculoskeletal and Skin Diseases. 4 April 2017. Retrieved 17 November 2023.
  7. ^ a b c d e f g h i j k l m n o p q r s t u Fleming R (May 2016). "Questions and Answers About Alopecia Areata". NIAMS. Archived from the original on 4 July 2017. Retrieved 10 July 2017.
  8. ^ Cite error: The named reference HordinskyJunqueira2015 was invoked but never defined (see the help page).
  9. ^ a b Cite error: The named reference occurrence was invoked but never defined (see the help page).
  10. ^ a b Freire P, Riera R, Martimbianco A, Petri V, Atallah AN (September 2019). "Minoxidil for patchy alopecia areata: systematic review and meta-analysis". Journal of the European Academy of Dermatology and Venereology. 33 (9): 1792–1799. doi:10.1111/jdv.15545. PMID 30835901. S2CID 73460786.
  11. ^ a b Yee BE, Tong Y, Goldenberg A, Hata T (April 2020). "Efficacy of different concentrations of intralesional triamcinolone acetonide for alopecia areata: A systematic review and meta-analysis". Journal of the American Academy of Dermatology. 82 (4): 1018–1021. doi:10.1016/j.jaad.2019.11.066. PMID 31843657. S2CID 209389315.
  12. ^ a b Erjavec SO, Gelfman S, Abdelaziz AR, Lee EY, Monga I, Alkelai A, et al. (February 2022). "Whole exome sequencing in Alopecia Areata identifies rare variants in KRT82". Nat Commun. 13 (1): 800. Bibcode:2022NatCo..13..800E. doi:10.1038/s41467-022-28343-3. PMC 8831607. PMID 35145093.
  13. ^ Rajabi F, Drake L, Senna M, Rezaei N (2018). "Alopecia areata: A review of disease pathogenesis". British Journal of Dermatology. 179 (5): 1033–1048. doi:10.1111/bjd.16808. PMID 29791718. S2CID 43940520.
  14. ^ Paggioli I, Moss J (December 2022). "Alopecia Areata: Case report and review of pathophysiology and treatment with Jak inhibitors". Journal of Autoimmunity. 133: 102926. doi:10.1016/j.jaut.2022.102926. PMID 36335798. S2CID 253320808.
  15. ^ a b Alkhalifah A, Alsantali A, Wang E, McElwee KJ, Shapiro J (February 2010). "Alopecia areata update: part I. Clinical picture, histopathology, and pathogenesis". Journal of the American Academy of Dermatology. 62 (2): 177–88, quiz 189–90. doi:10.1016/j.jaad.2009.10.032. PMID 20115945.
  16. ^ Spano F, Donovan JC (September 2015). "Alopecia areata". Canadian Family Physician. 61 (9): 751–755. ISSN 0008-350X. PMC 4569104. PMID 26371097.
  17. ^ Mounsey AL, Reed SW (August 2009). "Diagnosing and Treating Hair Loss". American Family Physician. 80 (4): 356–362. PMID 19678603. Archived from the original on 16 November 2022. Retrieved 16 November 2022.
  18. ^ a b Beigi PK (2018). Alopecia Areata: A Clinician's Guide. Springer. p. 14. ISBN 9783319721347. Archived from the original on 14 January 2023. Retrieved 1 October 2020.