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Alopecia areata

Last reviewed: 1 Nov 2024
Last updated: 23 Sep 2022

Summary

Definition

History and exam

Key diagnostic factors

  • hair loss
  • nonscarring alopecia
  • exclamation point hairs
  • normal underlying skin in bare areas
  • nail pitting
Full details

Other diagnostic factors

  • autoimmunity
Full details

Risk factors

  • autoimmune disease
  • family history of autoimmune disease
Full details

Diagnostic tests

1st tests to order

  • clinical diagnosis
  • positive hair pull test
Full details

Tests to consider

  • skin biopsy
  • trichoscopy
Full details

Treatment algorithm

ACUTE

limited hair loss (treatment desired)

limited hair loss (no treatment desired)

ONGOING

extensive hair loss (treatment desired)

extensive hair loss (no treatment desired)

Contributors

Authors

Fong Seng Lim, MBBS, MMed (FM), FAMS

Senior Consultant

Department of Family Medicine

National University Health System

Singapore

Disclosures

FSL declares that he has no competing interests.

Miny Samuel, PhD

Assistant Director

Research Support Unit

Yong Loo Lin School of Medicine

National University of Singapore

Singapore

Disclosures

MS declares that she has no competing interests.

Acknowledgements

Dr Fong Seng Lim and Dr Miny Samuel would like to gratefully acknowledge Dr Richard A. Strick, Dr Jack Green, and Dr Paradi Mirmirani, previous contributors to this topic. RAS is an honorary member of the National Alopecia Areata Foundation (NAAF) clinical scientific advisory board. JG is an author of a reference cited in this topic. PM declares that he has no competing interests.

Peer reviewers

Maria Hordinsky, MD

Professor and Chair

Department of Dermatology

University of Minnesota

Minneapolis

MN

Disclosures

MH declares that she has no competing interests.

Ralph M. Trueb, MD

Associate Professor

Department of Dermatology

University Hospital of Zurich

Zurich

Switzerland

Disclosures

RMT is an author of a number of references cited in this topic.

  • Alopecia areata images
  • Differentials

    • Trichotillomania
    • Tinea capitis
    • Telogen effluvium
    More Differentials
  • Guidelines

    • British Association of Dermatologists' guidelines for the management of alopecia areata 2012
    • Alopecia areata investigational assessment guidelines: part II
    More Guidelines
  • Patient information

    Alopecia areata

    More Patient information
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