Scabies

Last reviewed: 7 Sep 2022
Last updated: 05 Apr 2022

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
  • generalized and intense pruritus, typically worse at night
  • burrows
  • papules, vesicles, excoriations
  • positive ink burrow test
More key diagnostic factors

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
Other diagnostic factors

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
More risk factors

Diagnostic investigations

1st investigations to order

  • ectoparasite prep
More 1st investigations to order

Investigations to consider

  • skin biopsy
More investigations to consider

Emerging tests

  • epiluminescence light microscopy

Treatment algorithm

ACUTE

nonpregnant/nonlactating adults or children over 5 years

infants and children 2 months to 5 years and pregnant or lactating females

infants under 2 months

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.

  • Scabies images
  • Differentials

    • Impetigo
    • Xerotic dermatitis
    • Folliculitis
    More Differentials
  • Guidelines

    • Sexually transmitted infections treatment guidelines, 2021: ectoparasitic infections
    • European guideline for the management of scabies
    More Guidelines
  • Patient leaflets

    Scabies

    More Patient leaflets
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