By Gary M. White, MD
Acne keloidalis nuchae (AKN) is a papular and pustular eruption of the nape in darker-skinned men. Significant scarring may occur. A recent histologic study suggests that AKN is primarily an inflammatory process and that any infection or keloid formation is a secondary event.
The classic patient is a young, darker-skinned man with pustules and papules on the nape. Later, keloids may form and can become quite large. Central Centrifugal Alopecia may be seen on the vertex. Pseudofolliculitis Barbae may be associated.
If the patient's condition is aggravated by close shaving of the area or a rubbing collar, the hair should be allowed to grow long. The patient should not scratch, pick, rub, or excoriate the area.
A bacterial culture should be taken of any pustules to monitor for secondary bacterial infection. If positive, appropriate oral antibiotics may be given. If negative, an oral tetracycline (e.g., tetracycline 500 BID or doxycycline 100 BID) may be given. A potent topical steroid (usually a liquid e.g., clobetasol or a foam) should be given to reduce inflammation [Cutis 2005;75;317]. The patients are often kept on oral antibiotics and topical steroids for months to years. One common approach to inflammatory and/or keloidal papules and nodules is intralesional triamcinolone, e.g., 5-10 mg/cc monthly. If seborrheic dermatitis is present, it should be treated, e.g., with ketoconazole 2% shampoo.
Laser hair removal can be very helpful especially early, before large keloids have formed [Eur J Dermatol 2012;22;645]. Longer wavelength lasers sometimes do better in darker-skinned individuals. The 1064nm Nd-Yag laser has been recommended. UVB has also been used [BJD 2014;171;1156].
Surgery may be needed. A deep punch biopsy removes small papules. For larger keloids, a horizontal ellipse, including the posterior hairline and down to the subfollicular depth, may be done. The excision should be down to the fascia or at least to the deep subcutaneous tissue. Closure may be primary or by secondary intention.
Electrosurgical removal down to a clean base below the hair roots has been shown effective [J Drugs Dermatol 2010;9:1249–1257].