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Last reviewed: 19 Mar 2025
Last updated: 18 Jan 2023

Summary

Definition

History and exam

Key diagnostic factors

  • presence of risk factors
  • non-follicular vesicles and papules (all types)
  • asymptomatic eruption (crystallina)
  • clear non-inflammatory vesicles (crystallina)
  • fragile vesicles (crystallina)
  • paroxysmal pruritus and stinging (rubra)
  • erythematous papulovesicles (rubra)
  • anhidrosis (profunda)
  • compensatory hyperhidrosis (profunda)
  • flesh-coloured papules (profunda)

Other diagnostic factors

  • desquamative healing (crystallina)
  • weakness and malaise (profunda)
  • dyspnoea (profunda)
  • tachycardia (profunda)
  • hyperpyrexia (profunda)

Risk factors

  • profuse sweating
  • excessive heat and humidity
  • occlusive clothing
  • febrile illness
  • repeat episodes of miliaria rubra (for miliaria profunda)
  • ultraviolet light exposure
  • neonatal age
  • cholinergic medicines
  • isotretinoin
  • doxorubicin
  • staphylococcal scalded skin syndrome
  • atopic dermatitis

Diagnostic investigations

Investigations to consider

  • Tzanck smear
  • viral direct fluorescent antibody (DFA) or culture
  • viral polymerase chain reaction
  • bacterial culture
  • fungal culture
  • potassium hydroxide (KOH) preparation
  • skin biopsy

Treatment algorithm

Contributors

Authors

Brian L. Swick, MD
Brian L. Swick

Clinical Professor

Departments of Dermatology and Pathology

Iowa City Veterans Affairs Medical Center

Iowa City

IA

Disclosures

BLS declares that he has no competing interests.

Peer reviewers

Hobart W. Walling, MD, PhD

Dermatology Physician

Town Square Dermatology

Coralville

IA

Disclosures

HWW declares that he has no competing interests.

John English, MBBS, FRCP

Consultant Dermatologist

Department of Dermatology

Queen's Medical Centre

Nottingham University Hospitals

Nottingham

UK

Disclosures

JE declares that he has no competing interests.

Andrew D. Lee, MD, FAAD

Consultant Dermatologist

Yadkin Valley Dermatology

Affiliate of Hugh Chatham Memorial Hospital

Elkin

NC

Disclosures

ADL declares that he has no competing interests.

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