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Last reviewed: 16 Mar 2025
Last updated: 28 Mar 2023

Summary

Definition

History and exam

Key diagnostic factors

  • infants, children, and older adults
  • history of overcrowding
  • history of itching in family members or close contacts over the same period
  • generalised and intense pruritus, typically worse at night
  • burrows
  • papules, vesicles, excoriations
  • positive ink burrow test

Other diagnostic factors

  • papules on face, neck, palms, and soles in children
  • immunosuppression
  • bullae
  • thick, crusted lesions occurring on elbows, knees, hands, and feet with dystrophic nails
  • nodules

Risk factors

  • overcrowded living conditions/poverty
  • living in close quarters with others who are infected
  • age under 15 or over 65 years
  • sexual contact with new or multiple partners
  • immunosuppression
  • poor hygiene
  • contact with an infected animal
  • contact with contaminated clothing, towels, and bedding
  • winter season

Diagnostic investigations

Treatment algorithm

Contributors

Authors

Ryan Harris, MD

Dermatologist

Treasure Valley Dermatology and Skin Cancer Center

Boise

ID

Disclosures

RH declares that he has no competing interests.

Acknowledgements

Dr Ryan Harris would like to gratefully acknowledge Dr Pooja Khera and Dr Laura Korb Ferris, previous contributors to this topic.

Disclosures

PK and LKF declare that they have no competing interests.

Peer reviewers

David Cassarino, MD, PhD

Assistant Professor

Department of Pathology and Laboratory Medicine

University of California

Los Angeles

CA

Disclosures

DC declares that he has no competing interests.

Roderick J. Hay, DM, FRCP, FRCPath, FMedSci

Chairman

International Foundation of Dermatology

London

UK

Disclosures

RJH declares that he has no competing interests.

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