Gram-Negative Folliculitis Clinical Presentation

Updated: Aug 07, 2019
  • Author: Mordechai M Tarlow, MD; Chief Editor: William D James, MD  more...
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A history is helpful in suggesting the diagnosis of gram-negative folliculitis.

Patients usually have been receiving a course of antibiotics for a prolonged period. Patients with gram-negative folliculitis may present with one of two histories.

A history of apparent acne, usually of the nodulocystic form, may be present. The acne has not been responding to antimicrobial therapy or other therapy. A history of acne that has responded well to therapy and suddenly flares may be present.


Physical Examination

Because gram-negative folliculitis usually occurs in patients with existing acne, the development of this new process is often mistaken as an exacerbation of acne.

The morphology of the lesions is as follows:

  • Type 1 (approximately 80% of patients) - Superficial pustular lesions without comedones

  • Type 2 (approximately 20% of patients) - Deep, nodular, and cystic lesions

The distribution of the lesions is extending from the infranasal area to the chin and the cheeks.



Complications of gram-negative folliculitis are largely limited to expansion of infection, as well as potential permanent scarring. Of note, however, is the high potential for this condition to be missed when a diagnosis is attempted through telemedicine or direct-to-consumer telemedicine websites and smartphone apps. [10]