Last reviewed: July 2020
Last updated: June  2018



History and exam

Key diagnostic factors

  • recent history of immersion in spa water
  • man with dark skin and curly hair
  • recent ingestion of drugs known to be associated with folliculitis

Other diagnostic factors

  • recent history of shaving
  • umbilicated, flesh-colored papules
  • papules on one side of the face in the submaxillary area
  • small, uniform papules and pustules
  • background erythema
  • alopecia/scalp scaling
  • erythematous plaques with hemorrhagic crusts in a dermatomal distribution

Risk factors

  • trauma, including shaving and extraction
  • occlusion
  • perspiration
  • topical corticosteroid preparations
  • systemic antibiotics
  • diabetes mellitus
  • immunosuppression
  • immersion in underchlorinated water
  • drugs

Diagnostic investigations

Investigations to consider

  • Gram stain
  • potassium hydroxide (KOH) preparation
  • Tzanck smear
  • direct fluorescent antibody (DFA) assay
  • tissue culture
  • skin biopsy
More investigations to consider

Treatment algorithm


Clinical Research Fellow

Dermatology Department

Keck School of Medicine of USC

University of Southern California

Los Angeles



NEC declares that she has no competing interests.

April W. Armstrong

Associate Dean, Clinical Research

Associate Professor of Dermatology

Keck School of Medicine of USC

University of Southern California

Los Angeles



AWA has served as consultant for Abbvie, Amgen, Janssen, Merck, Eli Lilly, Novartis, and Pfizer; she has served as Investigator for Abbvie, Janssen, and Eli Lilly; and is a member of Speaker’s Bureau for Abbvie.

Dr April W. Armstrong would like to gratefully acknowledge Professor Howard Baden, a previous contributor to this monograph. HB declares that he has no competing interests.

Peer reviewersVIEW ALL

Professor of Dermatology

Dean Emeritus

School of Medicine and Dentistry

University of North Carolina

Chapel Hill



LG is editor-in-chief and co-founder of Logicalimages, Inc, which has print and electronic products for education and point-of-care; he has stock and stock options in that corporation. He is on the clinical and scientific advisory boards of Anacor Inc, which is developing anti-inflammatory and anti-infective products that are in early clinical trials; he receives payments and stock options for those services.

Head of Department

Department of Dermatology

St George Hospital

Conjoint Professor

University of New South Wales




DFM declares that she has no competing interests.

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