Last updated: August 2023
Also known as…Folliculitis keloidalis, folliculitis keloidalis nuchae, dermatitis papillaris capillitii, acne keloidalis, nuchal keloid acne, lichen keloidalis nuchae.
What is acne keloidalis nuchae?
Acne keloidalis nuchae (AKN) is a chronic inflammatory condition that affects hair follicles on the back of the neck. It may occur in combination with other conditions including hidradenitis suppurativa, dissecting cellulitis of the scalp, pilonidal sinus and acne conglobata.
The term AKN can be confusing because the condition is not acne and the scars formed are not true keloids.
Who gets acne keloidalis nuchae?
AKN is mostly seen in men of African-Caribbean background, but it may also be seen in those of Hispanic, Asian, Middle Eastern and Mediterranean backgrounds, and in rare cases, Caucasians.
It is 20 times more common in males than in females1.
What causes acne keloidalis nuchae?
The cause of AKN is poorly understood. Factors that may cause AKN include:
- frequent short haircuts
- chronic trauma (e.g. rubbing of shirt collar on the neck)
- curly hair
- ingrown hairs
What does acne keloidalis nuchae look like?
In the early stages of the condition, small firm bumps, pimples and crusts form around the hair follicles on the back of the scalp (occipital scalp). These papules can be painful and itchy.
As the condition progresses, the bumps become small scars that extend from the back of the neck up to the top of the scalp and then enlarge to become keloid-like masses.
In severe cases, irreversible scarring hair loss (alopecia) and/or abscesses with draining pus may occur. Tufted (“doll-like”) hairs may exist; these are multiple hair shafts from one hair follicle opening.
Figure 1. Acne keloidalis Nuchae on the back of the neck. Image reproduced with permission of Dr Michelle Rodrigues
How is acne keloidalis nuchae diagnosed?
AKN is diagnosed clinically through history and examination by finding bumps, pimples and scars on the scalp.
In some cases, a skin sample (biopsy) of the scalp may be required to diagnose AKN and distinguish it from other forms of scarring hair loss that look similar.
How is acne keloidalis nuchae treated?
Treatment options will vary depending on the individual and their needs.
AKN may often persist despite a variety of treatments. AKN treatment is aimed at preventing scarring and permanent hair loss, and may include:
- Avoiding frequent or short haircuts, close-shaving and tight collars.
- Topical steroids, antibiotics and retinoidcreams or shampoos.
- Steroid injections into the scar-like areas (intralesional corticosteroids).
- Oral retinoidsor oral anti-inflammatory medications.
- Physical therapies such as cryotherapy, ablative laser treatment and laser hair removal.
Surgical treatment or radiotherapy of the scarred area may be used for cases that are advanced or treatment resistant.
What is the likely outcome of acne keloidalis nuchae?
While there is no cure, AKN can be treated if diagnosed early.
It can be difficult to treat once scarring has developed. In severe cases, scarring can occur on affected areas of the scalp, resulting in hair loss.