Chapter 114. Pseudofolliculitis and Acne Keloidalis Nuchae

A 17-year-old young African American man comes to the office because, for the past 2 years, he has been bothered by the uncomfortable bumps on the back of his neck (Figure 114-1). He is an athletic young man, more than 6 feet tall, and likes to keep his hair short for his sports. He notices the bumps get irritated and larger when he shaves his hair. He also has bumps on his face that get worse when he shaves his face (Figure 114-2). He is diagnosed with pseudofolliculitis barbae and acne keloidalis nuchae. His treatment consisted of patient education and twice-daily tretinoin cream and 0.1% triamcinolone cream to the neck area and nightly tretinoin cream to the beard area. He was told he could use 1% hydrocortisone cream on his face as needed. It was suggested that he minimize shaving, if possible.

Pseudofolliculitis is a common skin condition affecting the hair-bearing areas of the body that are shaved (Figures 114-2, 114-3, 114-4). Potential complications include postinflammatory hyperpigmentation, bacterial superinfection, and keloid formation.

• Pseudofolliculitis—Razor bumps, shave bumps.
• Acne keloidalis nuchae—Folliculitis keloidalis.

• Pseudofolliculitis is most common in black men, with at least 50% of black men who shave being prone to the condition.1 In the beard area it is called pseudofolliculitis barbae, and when it occurs after pubic hair is shaved, it is referred to as pseudofolliculitis pubis. It may also occur in the neck area.
• Acne keloidalis nuchae occurs most often in black men but can be seen in all ethnicities (Figures 114-3 and 114-5). The lesions are often painful and cosmetically disfiguring.
• Both conditions are seen in women but far less often than in men (Figure 114-6).

• Pseudofolliculitis develops when, after shaving, the free end of tightly coiled hair reenters the skin, causing a foreign-body-like inflammatory reaction. Shaving produces a sharp free end below the skin surface. Tightly curled hair has a greater tendency for the tip to pierce the surface of the skin and form ingrown hairs. This explains the relative predominance of this condition in patients of African ethnicity. The hair eventually forms a loop and if the embedded tip is pulled out there may be spontaneous resolution of symptoms.
• The exact cause of acne keloidalis is uncertain. It often develops in areas of pseudofolliculitis or folliculitis. It may be associated with haircuts where the posterior hairline is shaved with a razor and with tightly curved hair shafts. Other possible etiologies include irritation from shirt collars, chronic bacterial infections, and an autoimmune process. It is a form of primary scarring alopecia.2 As such, multiple hairs can be seen growing from single follicle (hair tufts) in the midst of the keloidal scarring (Figure 114-7).

• Pseudofolliculitis:
  • African ethnicity.
  • Curly hair.
• Acne keloidalis nuchae:
  • Shaving the hair on the neck.
  • Pseudofolliculitis.

Clinical Features

• The diagnosis of pseudofolliculitis is based upon clinical appearance. A piece of hair often may be identified protruding from a lesion. Inflammation results in the formation of firm, skin-colored, erythematous or hyperpigmented papules that occur after shaving (Figures 114-2, 114-3, 114-4). Pustules may develop secondarily. The severity varies from a few papules or pustules to hundreds of lesions.
• Patients with acne keloidalis initially develop a folliculitis or pseudofolliculitis, which heals with keloid-like lesions, sometimes with discharging sinuses. It starts after puberty as 2- to 4-mm firm, follicular papules (Figure 114-1). More papules appear and enlarge over time (Figure 114-5). Papules may coalesce to form keloid-like plaques, which are usually arranged in a band-like distribution along the posterior part of the hairline (Figures 114-7 and 114-8).

Typical Distribution

• Pseudofolliculitis affects the hair-bearing areas of the body that are shaved, especially the face, neck, and pubic area (Figures 114-2, 114-3, 114-4).
• Acne keloidalis occurs on the occipital scalp and the posterior part of the neck (Figures 114-1, 114-5, and 114-7).

Biopsy

• Histologic evaluation of a biopsy may confirm either diagnosis but is usually not necessary.

• True folliculitis, which is an acute pustular infection of a hair follicle with more localized inflammation (see Chapter 117, Folliculitis).
• Impetigo, which presents with yellowish pustules or bullae that rupture and develop honey crusts, sometimes with adenopathy (see Chapter 116, Impetigo).
• Acne vulgaris, which presents with comedones and pustules usually including the forehead (see Chapter 112, Acne Vulgaris).

Nonpharmacologic

• Avoid close shaving, avoid all shaving, or permanently remove hair.3 Some occupations, however, such as the military and law enforcement, require facial shaving. Occasionally, a doctor's note will allow these men to go without shaving. In mild cases, shaving should be discontinued for a month. The beard can be coarsely trimmed with scissors or electric clippers during this time. Shaving should not resume until all inflammatory lesions have resolved. Warm Burow solution compresses may be applied to the lesions for 10 minutes, 2 times per day. Instruct the patient to search for ingrown hairs each day using a magnifying mirror and release them gently using a sterilized needle or tweezers. The hairs should not be plucked as this may cause recurrence of symptoms with hair regrowth (Figure 114-6). SOR C
• Chemical depilatories (Ali, Royal Crown, Magic Shave, and others) cause fewer symptoms than shaving.4 SOR B However, these creams can cause severe irritation, so testing a small amount on the forearm is important. They work by breaking the disulfide bonds in hair, which results in the hair being bluntly broken at the follicular opening instead of sharply cut below the surface. They should be used every second or third day to avoid skin irritation, although this can be controlled with hydrocortisone cream. Barium sulfide 2% powder depilatories can be made into a paste with water, applied to the beard, and removed after 3 to 5 minutes. Calcium thioglycolate preparations are left on 10 to 15 minutes, but the fragrances can cause an allergic reaction and chemical burns can result if it is left for too long.
• People who have acne keloidalis nuchae should avoid anything that causes folliculitis or pseudofolliculitis, such as getting their neck or hairline shaved with a razor.

Medications

• Topical eflornithine HCL 13.9% cream (Vaniqa; by prescription only) may be used to inhibit hair growth. It decreases the rate of hair growth and may make the hair finer and lighter. Unfortunately, this medication is expensive and requires daily application for continued efficacy. SOR C
• Twice-daily treatment with a class 2 or 3 corticosteroid may be sufficient to shrink pseudofolliculitis lesions and relieve symptoms (see Appendix B: Topical and Intralesional Corticosteroids). SOR C
• When pustules, crust formation, or drainage is present, use topical clindamycin or erythromycin. Unresponsive patients may be changed to a systemic antibiotic. SOR C
• Topical erythromycin, clindamycin, and combination clindamycin-benzoyl peroxide (BenzaClin, Duac) and erythromycin-benzoyl peroxide (Benzamycin) may be used once or twice daily.5 SOR B
• Oral doxycycline 100 mg bid, tetracycline 500 mg bid, or erythromycin 500 mg bid may be used for patients with more severe secondary inflammation. SOR C
• Tretinoin cream, 0.025%, may be useful in patients with mild disease, but is rarely helpful in moderate to severe cases.6 It is applied nightly for a week then reduced to every second or third night. Tretinoin may be used in conjunction with a mid-potency topical corticosteroid applied each morning. The mechanism of action is thought to be by relieving hyperkeratosis and “toughening” the skin. Topical combination cream (tretinoin 0.05%, fluocinolone acetonide 0.01%, and hydroquinone 4%) (Tri-Luma) adds an additional postinflammatory hyperpigmentation treatment. SOR C
• Intralesional steroid injections (10 to 20 mg/mL) may be used to soften and shrink keloids. Warn patients that this therapy may cause hypopigmentation (Figure 114-8). SOR C

Surgical

• The only definitive cure for pseudofolliculitis is permanent hair removal. Electrolysis is expensive, painful, and sometimes unsuccessful. Laser hair removal is fairly successful for treating pseudofolliculitis.7 SOR B Diode laser (810 nm) treatments have been proven safe and effective in patients with skin phototypes I to IV.8
• Excision of acne keloidalis lesions may be attempted. Recalcitrant keloidal lesions may be treated with removing individual papules with a small punch, or large keloids (Figure 114-9) with an elliptical excision closed with sutures. After removal, the wound edges should be injected with a mixture of equal amount of triamcinolone acetonide 40 mg/mL and sterile saline. Remove the sutures in 1 to 2 weeks and inject the edges every month with the above mixture for 3 to 4 times. SOR C Excision should extend into the subcutaneous tissue and the wound edges can be injected with 10 to 40 mg/mL of triamcinolone acetonide and be reapproximated. SOR C Recurrence is common, especially with shallow excisions or not treating with steroids.
• Other therapies that may be considered are laser therapy (carbon dioxide or Nd:YAG [neodymium:yttrium-aluminum-garnet]) followed by intralesional triamcinolone injections or cryotherapy for two 20-second bursts that are allowed to thaw and are then applied again a minute later. These methods may produce more pain and hypopigmentation. SOR C

• Termination of shaving prevents the development of pseudofolliculitis.

• No specific cure exists. If the patient is able to stop shaving, the problem usually disappears (except for any scar formation).

• Instruct patients to return if any complications occur. Otherwise have them return for possible initiation of intralesional steroid injections or topical steroid/retinoic acid therapy once the area has healed.

• For those who must shave, have the patient clip hairs no shorter than needed for maintenance. Use fine scissors or facial hair clippers if possible. When shaving, have the patient rinse with warm tap water for several minutes, use generous amounts of a highly lubricating shaving gel, and allow it to soften the skin for 5 to 10 minutes before shaving. The patient should always use sharp razors and shave in the direction of hair growth. Specialized guarded razors (e.g., PFB Bump Fighter) are available in pharmacies and by mail order. After shaving rinse the face with tap water, and then apply cold water compresses.
• With acne keloidalis, instruct males who play football to make sure their helmets fit properly and do not cause irritation on the posterior part of the scalp. They should avoid having the posterior part of the hairline shaved with a razor as part of a haircut, and discontinue wearing garments that rub or irritate the posterior parts of the scalp and the neck.

Patient Resources

• American Osteopathic College of Dermatology. Pseudofolliculitis— http://www.aocd.org/skin/dermatologic_diseases/pseudofolliculitis.html.
• Skin Channel. Acne Keloidalis Nuchae—http://skinchannel.com/acne/acne-keloidalis-nuchae/.

Provider Resources

• eMedicine. Pseudofolliculitis—http://emedicine.medscape.com/article/1071251.
• eMedicine. Acne Keloidalis—http://emedicine.medscape.com/article/1072149.
• DermNet NZ. Acne Keloidalis—http://dermnetnz.org/acne/keloid-acne.html.