Pili annulati explained

Pili annulati
Synonyms:Ringed hair disease

Pili annulati (also known as "ringed hair") is a genetic trait in which the hair seems 'banded' by alternating segments of light and dark color when seen in reflected light.[1] [2] [3] [4]

Pili annulati manifests during infancy or at birth. The clinical manifestation varies. Usually, the hair appears shiny and banded. Pili annulati usually just affects the scalp but can be present in other areas.

Pili annulati may be sporadic or inherited in an autosomal dominant fashion. Pili annulati can be diagnosed based on light microscopy or trichoscopy. Treatment is not needed.

Pili pseudoannulati is an anomaly of human hair that mimics pili annulati; however, the two differ in that the light bands of pili annulati are caused by internal effects, whereas the bright segments of pili pseudoannulati are caused by reflection and refraction of light by flattened, twisted surfaces of hair.[2]

Signs and symptoms

Pili annulati might show up during infancy or at birth.[5] Within the same patient, the clinical manifestation may vary at different parts of the scalp or even within the same afflicted hair.[6] [7] [8]

The clinical examination typically finds the hair to be shiny and banded, with an occasional odd shimmering texture or even frizzy look.[9] As the hair develops, the amount of white bands tends to diffuse.[10]

Higher hair fragility is not usually linked to pili annulati.[10] A small percentage of cases show significant trichorrhexis-nodosa-like hair fracturing and breakage together with enhanced sensitivity at the light band level.[11] [12]

Although pili annulati is mostly restricted to the hair on the scalp, it can also affect hair in the pubic, axillary, and beard areas.[9] [7]

Causes

Pili annulati are inherited in an autosomal dominant pattern that exhibits varied expression. There has also been sporadic cases reported.[10] There is documentation of a case of pili annulati linked to a mutation in RECQL4, which causes Rothmund-Thomson syndrome.[6]

Diagnosis

A distinctive look with alternating bright and dark stripes in the hair shaft is revealed by light microscopy. In light microscopy, the dark bands correlate to white bands in reflected light, in trichoscopy, and macroscopically. A normal medulla with clusters of sporadic, air-filled cavities within the cortex of the hair shafts is visible under transmission electron microscopy of the affected hairs.[10] A "cobblestoned" and fluted cuticle is shown via scanning electron microscopy.[5] [13]

Similar to other illnesses of the hair shaft, trichoscopy is a quick and easy way for practitioners to diagnose pili annulati without having to remove hairs.[10]

Treatment

Since pili annulati is a benign illness for which individuals never seek medical attention, treatment is frequently not necessary.[10]

See also

Further reading

External links

Notes and References

  1. Book: Rapini, Ronald P. . Bolognia, Jean L. . Jorizzo, Joseph L. . Dermatology: 2-Volume Set . Mosby . St. Louis . 2007 . 978-1-4160-2999-1 .
  2. James, William; Berger, Timothy; Elston, Dirk (2005). Andrews' Diseases of the Skin: Clinical Dermatology. (10th ed.). Saunders. .
  3. Freedberg, et al. (2003). Fitzpatrick's Dermatology in General Medicine. (6th ed.). McGraw-Hill. .
  4. Web site: OMIM Entry - % 180600 - RINGED HAIR.
  5. Amichai . B. . Hair abnormality present since childhood. Pili annulati . Archives of Dermatology . American Medical Association (AMA) . 132 . 5 . 1996-05-01 . 0003-987X . 10.1001/archderm.132.5.575 . 575. 8624159 .
  6. Rudnicka . Lidia . Olszewska . Małgorzata . Waśkiel . Anna . Rakowska . Adriana . Trichoscopy in Hair Shaft Disorders . Dermatologic Clinics . Elsevier BV . 36 . 4 . 2018 . 0733-8635 . 10.1016/j.det.2018.05.009 . 421–430. 30201151 .
  7. Teysseire . S. . Weiler . L. . Thomas . L. . Dalle . S. . Pili Annulati . Annales de Dermatologie et de Vénéréologie . Elsevier BV . 144 . 5 . 2017 . 0151-9638 . 10.1016/j.annder.2016.12.003 . 399–400 . 28109542 . fr.
  8. Laniosz . Valerie . Podjasek . Joshua O. . Camilleri . Michael J. . Hand . Jennifer L. . Pili Annulati Masquerading As Hypotrichosis . Pediatric Dermatology . Wiley . 30 . 4 . 2013 . 0736-8046 . 10.1111/pde.12111 . 510–511. 23819454 .
  9. Theodosiou . G . Hamnerius . N . Svensson . A . Banded Scalp Hair with an Unusual Glistening Appearance in a Teenager: A Quiz . Acta Dermato Venereologica . Medical Journals Sweden AB . 98 . 4 . 2018 . 0001-5555 . 10.2340/00015555-2891 . 473–474. free .
  10. Web site: Chabchoub . Ines . Souissi . Asmahane . Pili Annulati . StatPearls Publishing . 2023-06-26 . 31082025 . 2024-03-23.
  11. Osório . Filipa . Tosti . Antonella . Pili annulati – What about racial distribution? . Dermatology Online Journal . 18 . 8 . 2012-08-01 . 1087-2108 . 10.5070/D323H0G5QZ .
  12. Nam . Chan Hee . Park . Minkee . Choi . Mi Soo . Hong . Seung Phil . Kim . Myung Hwa . Park . Byung Cheol . Pili Annulati with Multiple Fragile Hairs . Annals of Dermatology . Korean Dermatological Association and The Korean Society for Investigative Dermatology . 29 . 2 . 2017 . 254–256 . 1013-9087 . 10.5021/ad.2017.29.2.254 . 28392665 . 5383763 .
  13. Moffitt . DL . Lear . JT . de Berker . DA . Peachey . RD . Pili annulati coincident with alopecia areata. . Pediatric Dermatology . Wiley . 15 . 4 . 1998 . 0736-8046 . 10.1046/j.1525-1470.1998.1998015271.x . 271–273. 2024-06-21 . 9720689 .

This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Pili annulati".

Except where otherwise indicated, Everything.Explained.Today is © Copyright 2009-2024, A B Cryer, All Rights Reserved. Cookie policy.