April 2020

Acne keloidalis nuchae (AKN) is a condition characterised by longstanding inflammation in the scalp leading to scar formation and hair loss over the nape of the neck and occipital area (i.e. back of the head).  Its reported incidence varies between 0.45-9% and most commonly affects men of African origin.  It is otherwise known as folliculitits keloidalis, acne keloidalis or folliculitis keloidalis nuchae (1).

Acne keloidalis nuchae 

AKN disease mechanisms

The exact mechanisms underlying this condition are not fully understood.  Predominant theories include individual responses to skin injury as well as an intense immune reaction within the hair follicle unit (2).

Risk factors for the development of AKN (3)

  • Family history
  • Male sex (males are 20 times more likely to develop AKN compared to females)
  • Young age (condition most commonly develops in adolescence/early adulthood)
  • Dark type skin and curly hair
  • Hormonal influences (especially testosterone)
  • Frequent injury to the scalp e.g. close shaving and hair cutting practices

Natural course of AKN (1, 3)

  • Formation of red inflamed raised papules (bumps)
  • Secondary infection and abscess formation
  • Continued inflammation leads to scarring and potentially large bulky scar masses
  • Alopecia (hair loss)

Prevention (4)

Measures to prevent the formation of AKN include:
Avoid irritation from closely fitting caps/collars/helmets, clothing
Refrain from aggressive hair grooming practices (e.g. short haircuts/ close shaves)
Practice good topical hygiene with antimicrobial (chlorhexidine or benzoyl peroxide based) cleansers/shampoos.

Treatment options

Medical treatment 

For mild cases of AKN, oral or topical antibiotics and steroid injections can improve symptoms by minimising secondary infections and decreasing inflammation (1).  These courses are typically lengthy and recurrence after the course of therapy is common. Reported side effects of steroids include skin thinning, white translucent plaques, visible blood vessels, and changes to the color of the skin.

Surgery 

A number of surgical techniques have been described in the literature including:
a) Removal of the involved area of skin and dressings over a prolonged period of time or direct closure of the skin edges (5). 
b) Cauterisation (i.e. burning or freezing off) treatment using either electrosurgery or liquid nitrogen (6).
c) Tissue expansion. If the affected area/scar bulk is extensive, tissue expansion is a valid option, in which case an inflatable balloon is inserted (under an anaesthetic) close to the involved area of skin. The expander is gradually inflated as an outpatient procedure and once enough skin has been generated from the expansion, the scarred area is removed and the ‘extra skin’ is draped over the resulting defect to allow wound closure (7).

Other adjuncts

  • If the scar has reached a keloidal stage, then radiotherapy is the most effective option to minimise recurrence i.e. bulky scar formation following surgery (8).
  • A variety of laser modalities have been described in order to decrease the inflammatory response by targeting the blood vessels and hair follicles in the affected area.  Modalities recommended include the 810nm diode and 1064nm Nd:YAG lasers, which appear to be most effective in controlling symptoms and decreasing the size of the AKN papules/scars (9,10).

I think I may suffer with acne keloidalis nuchae (AKN), what should I do?

You are encouraged to seek a referral with a health professional who has an expertise in skin disease/scar management.  Early diagnosis and specialist advice are both vital for successful management of the condition.

Ioannis Goutos, Consultant Plastic Surgeon
Specialist Interest in Scar Management

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References

1) Maranda EL, Simmons BJ, Nguyen AH, Lim VM, Keri JE.  Treatment of acne keloidalis nuchae: a systematic review of the literature.  Dermatol Ther 2016; 6:363-78.

2) Sperling LC, Homoky C, Pratt L, Sau P.  Acne kelloidalis is a form of primary scarring alopecia.  Aech Dermatol.  2000; 136(4): 479-84.

3) Ogunbiyi A.  Acne keloidalis nuchae: prevalence, impact, and management challenges.  Clinical, Cosmetic and Investigational Dermatology 2016; 9:483-9.

4) Alexis A, Heath CR, Halder RM.  Folliculitis keloidalis nuchae and pseudofolliculitis barbae; are prevention and effective treatment within reach? Dermatol Clin 2014; 32(2): 183-91.

5) Gloster HMJ.  The surgical management of extensive cases of acne keloidalis nuchae.  Arch Dermatol 2000; 136(11): 1376-9.

6) Beckett N, Lawson C, Cohen G.  Electrosurgical excision of acne keloidalis nuchae with secondary intention healing.  J Clin Aesthet Dermatol.   2011; 4(1): 36-9.

7) Pestalardo CM, Cordero AJ, Ansorena JM, Bestue M, Martinho A.  Acne keloidalis nuchae.  Tissue expansion treatment.  Dermatol Surg.  1995; 21(8): 723-4.

8) Millan-Cayetano JF, Repiso-Jimenez JB, Del Boz J, de Toya-Martin M.  Refractory acne keloidalis nuchae treated with radiotherapy.  Australas J Dermatol 2015.  Doi:10.1111/ajd.12380.

9) Shah GK.  Efficacy of diode laser for treating acne keloidalis nuchae.  Indian J Cermatol Veneorol Leprol.  2005; 71(1):31-4.

10) Esmat SM, Hay RMA, Zeid OMA, Hosni HN.  The efficacy of laser assisted hair removal in the treatment of acne keloidalis nuchae; a pilot study.  Eur J Dermatol 2012; 22(5): 645-50.