AUTHOR AND EDITOR INFORMATION

Section 1 of 10  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Multimedia
• References

INTRODUCTION

Section 2 of 10  

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• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Multimedia
• References

Background

Acne keloidalis nuchae (AKN) refers to the occurrence of keloidlike papules and plaques on the occipital scalp and the posterior part of the neck, almost exclusively in African American men. Initially, patients usually develop a chronic folliculitis and perifolliculitis of the occipital part of the scalp and the posterior part of the neck, which heal with keloidlike lesions, sometimes with discharging sinuses. They often coalesce to form one or several large plaques, which gradually enlarge for years. The lesions are often painful and cosmetically disfiguring.

Kaposi first described acne keloidalis in 1869 as dermatitis papillaris capillitii. The disease had previously been known in Hebra's clinic and is described and pictured in Hebra's atlas under the name sycosis framboesiformis. Three years after Kaposi's publication, Bazin named the condition acne keloidalis. Since then, the disease has appeared in the literature under a variety of names (see Synonyms, Key Words, and Related Terms).

Little can be added clinically to Adamson's description of AKN in 1914. The eruption occurs on the upper posterior neck in the form of a raised transverse band at the lower margin of the hairy scalp. The band is usually dusky red in color, smooth and firm to the touch, and of keloidal consistency. It is hairless except at its upper margin, which is abrupt, broken into nodules and fringed with hair in tufts, like aigrettes, or the bunches of bristles in a brush. There may be pustules or crusted nodules here and there along the upper border. The lower margin slopes gradually to the normal skin. Usually there are no comedones or follicular pustules of acne when the patient comes under observation, and there may or may not be a history of acne of the face in youth. Often the patient complains of itching at the site of the eruption.

Pathophysiology

The exact cause of AKN is still speculative. Injury produced by short haircuts (especially when the posterior hairline is shaved with a razor, a practice common in African American men) and curved hair follicles (analogous to pseudofolliculitis of the beard in African Americans) may be the precipitating factors. Other frequently suggested etiologic possibilities are constant irritation from shirt collars, chronic low-grade bacterial infections, and an autoimmune process (AKN usually responds to systemic steroid therapy). The use of antiepileptic drugs and an increased number of mast cells in the occipital region have also been indicated as causes.

The recent findings of Sperling et al indicate that AKN is a primary form of scarring alopecia. Many of the histologic findings closely resemble those found in certain other forms of scarring alopecia. They claim that overgrowth of microorganisms does not play an important role in the pathogenesis of AKN. They also found no association between pseudofolliculitis barbae and AKN.

Herzberg et al provided another explanation based on extensive transverse microscopy, histochemistry, and electron microscopy. Herzberg et al described the following hypothetical sequence of inflammatory events that take place in AKN:

The acute inflammation, whether it begins in the sebaceous gland or elsewhere in the region of the deep infundibular or isthmus levels, is a cause or the result of a weakened follicular wall at these levels. This enables the release of hair shafts into the surrounding dermis. The "foreign" hairs incite further acute and chronic granulomatous inflammation. The localized granulomatous inflammation manifests itself clinically as a papular lesion. Fibroblasts lay down collagen and scars form in the region of the inflammation. Distortion and occlusion of the follicular lumen by fibrosis leads to hair retention in the inferior follicle and further smoldering granulomatous inflammation and scarring. The scarring and granulomatous inflammation manifest themselves clinically as keloidlike scars and plaques.

They also found that the follicular lymphocytic infiltrate contained a mixed B- and T-cell population and that the plasma cell immunoglobulins are of a polyclonal nature.

Frequency

United States

AKN is said to represent 0.45% of all dermatoses affecting black persons.

Mortality/Morbidity

AKN is a medically benign but often psychologically devastating dermatosis. Squamous cell carcinoma has developed secondary to radiation therapy in rare cases. Chronic pruritus, scarring, and drainage may occur. Without therapy, the lesions may continue to enlarge and sometimes coalesce, and new ones may appear. Scarring alopecia of the involved scalp is a common finding.

Race

AKN most often occurs in African Americans. Hispanics are the next most common group, followed by Asians and (least often) whites.

Sex

Although the early literature inferred that AKN occurred only in males, it is now known to occur in females. The male-to-female ratio is approximately 20:1.

Age

Onset usually occurs in early adulthood, but some cases do develop during adolescence. Onset prior to puberty or after age 50 years is extremely rare.

CLINICAL

Section 3 of 10  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Multimedia
• References

History

Take a history before initiating medical care to ascertain the duration of disease, the duration of the acute flare, past therapeutic successes and failures, present medications, hair grooming techniques, and any known allergies.

• Early papular lesions are usually asymptomatic, but pustular lesions are often pruritic and occasionally painful.
• Large lesions are often painful.
• Older lesions with abscesses and sinuses may emit an odorous discharge.
• Hats, shirts, jackets, and sweaters may irritate the involved area, thereby causing patients to alter their preferred style of dress.
• Even if large lesions are asymptomatic, they are often a cause of great cosmetic concern.

Physical

• AKN starts after puberty as firm, dome-shaped, follicular papules that are 2-4 mm in diameter.
• The papules develop on the nape of the neck and/or on the occipital part of the scalp.
• Pustules may be present in the same areas, but they are usually short-lived because the tops are scratched off in response to pruritus or because they are traumatized when the patient's hair is combed and/or brushed.
• Comedones are not present (in contradistinction to acne).
• More papules may appear and enlarge as the disease progresses.
• Some papules coalesce to form keloidlike plaques, which are usually arranged in a bandlike distribution at or below the posterior part of the hairline (see Media Files 1-2).
• Plaques are usually only a few centimeters in diameter, but they sometimes reach more than 10 cm in diameter.
• Even when the plaques are smaller, the numerous papules and plaques may involve an area greater than 14 cm in diameter (see Media Files 3-4).
• Hair is usually lost in large lesions, which have upper borders that are often fringed with tufts of polytrichia producing doll-like hair (see Media File 5).
• Scarring alopecia and subcutaneous abscesses with draining sinuses may also be present.

Causes

The cause of AKN is speculative. Injury produced by short haircuts (especially when the posterior part of the hairline is shaved with a razor, a practice common in African American men) and curved hair follicles (analogous to pseudofolliculitis of the beard in African Americans) may be precipitating factors. Other frequently suggested etiologic possibilities include the following:

• Constant irritation from shirt collars
• Chronic low-grade bacterial infections
• An autoimmune process (AKN usually responds to systemic steroid therapy.)
• Use of antiepileptic drugs
• An increased number of mast cells in the occipital region (Mast cells are increased in keloids.)

DIFFERENTIALS

Section 4 of 10  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Multimedia
• References

Other Problems to be Considered

Regular keloids (when history of trauma exists)
Nevus sebaceous of Jadassohn
Folliculitis decalvans dissecting cellulitis
Oil folliculitis
Pediculosis capitis
Pseudofolliculitis barbae

WORKUP

Section 5 of 10  

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• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Multimedia
• References

Lab Studies

• A bacterial culture and sensitivity from any pustular or draining lesions should be taken intermittently. If pathogens are present, appropriate antibiotics should be prescribed.

Procedures

• Evaluation of a biopsy sample is the essential laboratory study to confirm the clinical diagnosis.

Histologic Findings

Follicular and perifollicular infiltration occurs, the composition of which changes with time. The initial infiltrate has been described as being composed of neutrophils and lymphocytes, while others claim that plasma cells are predominant early on. The folliculitis begins at the upper one third of the hair follicle. Sebaceous glands are markedly diminished or absent in all stages of folliculitis. In more advanced lesions, hair follicles are disrupted, and broken hair fragments are surrounded by granulomatous inflammation. Dermal fibrosis and scarring are seen at this stage and resemble the collagen fibers seen in scar tissue rather than that seen in true keloids. One follicle can show several stages of inflammation at any given time when followed throughout its length. The lower portion of the follicle (including the matrix) is relatively spared until later in the disease process. These hairs have no shaft to guide them to the surface and thus probably proliferate beneath fibrotic tissue, producing themultiple hair fragments that are seen late in the lesions. A foreign body response surrounds these hair fragments. Polytrichia hairs are found in the upper dermis; the hairs have separate follicles in the lower dermis. The inflammation and scar tissue seem to cause this amalgamation of hair in one follicle.

TREATMENT

Section 6 of 10  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Multimedia
• References

Medical Care

After a thorough history, obtain a specimen for bacterial culture and sensitivity. A biopsy should be performed if the presentation is not typical.

• The first line of defense against AKN is prevention (as with many other cutaneous disorders). People who have this problem should not get the occipital part of their hairline edged with a razor or wear tight fitting shirts or other clothing that will cause mechanical irritation of the posterior part of their hairline. Initiating therapy quickly lowers the patient's chances of developing large lesions.
• Twice-a-day treatment with a combined retinoic acid (Retin-A) and a class 2 or 3 corticosteroid cream or gel may be sufficient to relieve all symptomatology and flatten the existing lesions. This mixture seems to be somewhat more effective than class 1 or 2 steroids alone.
• When pustules, crust formation, or drainage is present, use topical clindamycin on a twice-daily basis until the pustules abate and the inflammation subsides. If the patient does not have significant improvement in 4-5 days, take a bacterial culture of the involved area, and start the appropriate systemic antibiotic. In the rare cases where large abscesses or draining sinuses are present, give patients a 7- to 10-day course of prednisone after starting appropriate systemic antibiotics.
• Intralesional steroid injections (10-40 mg/mL) are another method of therapy. Injections are easier if the papules are electrodesiccated and curetted first. Application of a lidocaine-prilocaine cream mixture under plastic film occlusion 2 hours prior to injection decreases the pain of injections. Warn patients that the area injected might become hypopigmented, which may remain for 6-12 months.
• Laser therapy (carbon dioxide or Nd:YAG) has been successful for some patients. Postoperative intralesional triamcinolone injections (10 mg/mL q2-3wk) help prevent recurrence. Cryotherapy has also proven to be successful in some cases. The area is frozen for 20 seconds, allowed to thaw and is then frozen again a minute later. The morbidity (discomfort and drainage) is greater than other modalities, and the treated site often becomes hypopigmented and may remain so for 12-18 months (when the thaw time is >25 seconds, melanocytes are destroyed and the treated area often becomes hypopigmented, especially in patients with dark skin).
• Once healing has taken place, apply a tretinoin-fluorinated steroid mixture to the occipital part of the scalp twice daily to help prevent recurrence.

Surgical Care

• Removing each papule with a hair transplant punch is the next therapeutic option if combined retinoic acid/corticosteroid treatment is not successful. The punch should extend deep (past the deepest level of the hair follicle) into the subcutaneous tissue, as superficial removal seems to have a much higher incidence of recurrence. After removal, inject the wound edges with a bolus of Kenalog 40 mg, and, then, it should be closed with 4-0 sutures. Or, use an equal amount of 2% lidocaine with epinephrine and triamcinolone acetonide at 40 mg/mL to anesthetize the surgical site.
  • The ends of the nylon sutures often irritate the skin if patients sleep on their back or have a short neck. Use silk sutures to prevent this problem. Instruct patients to clean the postoperative area 3 times a day with alcohol or sodium chloride solution followed by the application of a topical antibiotic ointment.
  • Remove the sutures in 6-14 days, and start patients on a twice-daily topical retinoic acid/corticosteroid regimen for 4-6 weeks.
  • Kenalog (10-40 mg/mL) is also injected into the postoperative site or sites every 2-3 weeks for 4 sessions, starting 1 week after suture removal.
• The preferred method of removal for larger linear lesions (1 cm or less in diameter) is a horizontal ellipse for excision with primary closure. The base of the excision should extend below the hair follicles. Close the postoperative site with 4-0 silk sutures.
• • Postoperative care is the same as with punch grafts.
  • The postoperative site often splays to the diameter of the initial excision. Always remember when closing primarily not to close when the posterior part of the neck is flexed or patients will spend a week or more having to look upward. Under this amount of tension, the resultant scar splays and will be the same size as the amount of area removed, often creating an area of alopecia as large as the initial defect.
• For large lesions that cannot be excised and closed primarily, the area of AKN is excised to the fascia or to the deep subcutaneous tissue and left to heal secondarily.
• • Prior to performing surgery, tell both the patient and the caregiver providing the postoperative care (clean postoperative site twice a day with alcohol or sodium chloride solution, and apply an antibiotic ointment) that the postoperative site will be cosmetically unacceptable initially, and the patient will experience pain and discomfort for the first few days.
  • Complete wound healing takes 8-12 weeks. Give patients explicit verbal and written postoperative care instructions.
  • If possible, show patients and postoperative caregivers a set of photographs showing the before; immediate postoperative, 1-week postoperative, and monthly postoperative healing progression; and final healing.
  • Initiate a broad-spectrum antibiotic (eg, erythromycin) on the day of surgery and continue for 10 days because sterilizing the scalp is impossible.
  • Tie off or coagulate all bleeders after excision. Then, apply pressure to the postoperative site for 10 minutes, and check for bleeding again. If most of the oozing has stopped, apply an antibiotic ointment to minimize bacterial colonization, and place a nonadherent dressing (eg, Telfa, Vaseline gauze, adaptic) over the defect. Wrap gauze over the dressing to help secure it and absorb the exudate. Use paper tape to secure the gauze.
  • Pain medication may be necessary for the first 48 hours.
  • Have patients return in 24-36 hours (preferably with the person responsible for changing dressings) for removal of the initial dressing. Soak the area with sodium chloride solution not only to facilitate the removal of the dressing but also to clean the postoperative site.
  • Instruct patients to start cleaning the site twice a day (following the regimen above) once the dressing is removed.
  • Instruct patients to return for follow-up visits in 1 and 3 weeks or sooner if any complications occur. Visits thereafter are necessary only on an as-needed basis.
  • Instruct patients to return for follow-up care for possible initiation of topical steroid/retinoic acid therapy once the area has healed, usually in 2-3 months.
  • A follicular papule or pustule occasionally develops along the border of the linear scar. Treat all inflammatory lesions with topical clindamycin until the infection subsides and then remove the lesions with the hair transplant punch method.
• Excision with grafting is not as cosmetically acceptable because it results in a large depressed non–hair-bearing area.
• Optimal healing with second intention healing is achieved when the excision is a horizontal ellipse of the posterior part of the scalp, including the posterior part of the hairline, and extends to the level of the muscle fascia or the deep subcutaneous tissue.
• • Healed second intention scars are almost imperceptible, especially when the occipital region of hair is allowed to grow long.
  • Do not give corticosteroid injections prior to complete wound closure because they prevent wound contraction.

MEDICATION

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The goals of pharmacotherapy are to reduce morbidity and to prevent complications.

Drug Category: Corticosteroids

These agents have anti-inflammatory properties and cause profound and varied metabolic effects. Corticosteroids modify the body's immune response to diverse stimuli. Class 2 or 3 topical steroid creams or gels (eg, Elocon cream, topical cream or gel, Lidex cream or gel) may be mixed with equal parts of retinoic acid; this should be applied bid.

Drug Name	Prednisone (Deltasone, Meticorten, Orasone)
Description	May decrease inflammation by reversing increased capillary permeability and suppressing PMN activity. Used when patient has acute flare.
Adult Dose	40-80 mg PO every morning
Pediatric Dose	Not established
Contraindications	Documented hypersensitivity; viral, fungal, tubercular skin, or connective tissue infections; peptic ulcer disease; hepatic dysfunction; GI disease
Interactions	Coadministration with estrogens may decrease clearance; concurrent use with digoxin may cause digitalis toxicity secondary to hypokalemia; phenobarbital, phenytoin, and rifampin may increase metabolism of glucocorticoids (consider increasing maintenance dose); monitor for hypokalemia with coadministration of diuretics
Pregnancy	C - Safety for use during pregnancy has not been established.
Precautions	Abrupt discontinuation of glucocorticoids may cause adrenal crisis; hyperglycemia, edema, osteonecrosis, myopathy, peptic ulcer disease, hypokalemia, osteoporosis, euphoria, psychosis, myasthenia gravis, growth suppression, and infections may occur with glucocorticoid use

Drug Name	Clobetasol propionate (Olux foam) or Mometasone (Elocon)
Description	May depress formation, release, and activity of endogenous chemical mediators of inflammation. Available as 0.025%, 0.05%, and 0.1% cream (Elocon) and as a 0.05% foam (Olux).
Adult Dose	Mix with equal parts of retinoic acid and apply bid sparingly to affected areas; do not use occlusive dressing
Pediatric Dose	Not established
Contraindications	Documented hypersensitivity; fungal, viral, or tubercular skin lesions; herpes simplex or herpes zoster
Interactions	None reported
Pregnancy	C - Safety for use during pregnancy has not been established.
Precautions	Use over large or denuded areas of the body for prolonged periods of time with an occlusive dressing or on infants may produce adverse systemic effects

Drug Name	Fluocinonide (Lidex, Fluonex)
Description	High-potency topical corticosteroid that inhibits cell proliferation; has immunosuppressive and anti-inflammatory properties.
Adult Dose	Mix with equal parts of retinoic acid and apply bid sparingly to affected areas; do not use occlusive dressing
Pediatric Dose	Not established
Contraindications	Documented hypersensitivity; herpes simplex infection; fungal, viral, or tubercular skin lesions
Interactions	None reported
Pregnancy	C - Safety for use during pregnancy has not been established.
Precautions	May cause adverse systemic effects if used over large areas, denuded areas, on occlusive dressings, or during prolonged treatment periods

Drug Category: Retinoids

These agents decrease the cohesiveness of abnormal hyperproliferative keratinocytes, and they may reduce the potential for malignant degeneration. They modulate keratinocyte differentiation. They have been shown to reduce the risk of skin cancer formation in patients who underwent renal transplantation.

Drug Category: Antibiotics

Empiric antimicrobial therapy must be comprehensive and should cover all likely pathogens in the context of this clinical setting.

Drug Name	Mupirocin (Bactroban)
Description	Topical antibiotic; inhibits bacterial growth by inhibiting RNA and protein synthesis.
Adult Dose	Apply topically bid
Pediatric Dose	Apply as in adults
Contraindications	Documented hypersensitivity
Interactions	None reported
Pregnancy	B - Usually safe but benefits must outweigh the risks.
Precautions	Prolonged use may result in the growth of nonsusceptible organisms

FOLLOW-UP

Section 8 of 10  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Multimedia
• References

Deterrence/Prevention

• Instruct males who play football to make sure their helmets fit properly and do not cause irritation on the posterior part of the scalp.
• Patients, especially African Americans, should avoid having the posterior part of the hairline shaved with a razor as part of a haircut.
• Patients should discontinue wearing garments that rub or irritate the posterior parts of the scalp and the neck.

Complications

• Keloidlike scarring, scarring alopecia, and chronic discharge are complications of AKN.

Prognosis

• The prognosis is good if AKN is treated early and properly.
• Once major scarring develops, therapy is more difficult and morbidity is increased.

Patient Education

• Educate patients on the probable underlying causes of their AKN.
• Advise patients to discontinue wearing possible offending garments.
• Instruct patients to tell their barbers not to shave the posterior part of their hairline.
• Counsel patients about scalp folliculitis and how to care for it.
• For excellent patient education resources, visit eMedicine's Skin, Hair, and Nails Center and Teen Health Center. Also, see eMedicine's patient education articles Acne.

MULTIMEDIA

Section 9 of 10  

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• Differentials
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• Follow-up
• Multimedia
• References

Media file 1:  A large acne keloidalis plaque on the occipital region in an African American patient. This man also had perifolliculitis of the scalp and acne conglobata (the follicular occlusion triad).
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Media type:  Photo

Media file 2:  A large acne keloidalis plaque with surrounding papules on the occipital region in an African American man.
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Media type:  Photo

Media file 3:  Numerous acne keloidalis papules and plaques in a white man with straight hair.
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Media type:  Photo

Media file 4:  Numerous acne keloidalis papules and plaques involving a large area on the occipital region in an African American man.
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Media type:  Photo

Media file 5:  A large acne keloidalis plaque that is fringed with tufts of polytrichia (many hairs coming out of the same hair follicle).
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Media type:  Photo

REFERENCES

Section 10 of 10

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
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• Follow-up
• Multimedia
• References

• Adamson HG. Dermatitis papillaris capillittii (Kaposi). Acne keloid. Br J Dermatol. 1914;26:69-83.
• Blackburn WR, Cosman B. Histologic basis of keloid and hypertrophic scar differentiation.Clinicopathologic correlation. Arch Pathol. Jul 1966;82(1):65-71. [Medline].
• Califano J, Miller S, Frodel J. Treatment of occipital acne keloidalis by excision followed by secondary intention healing. Arch Facial Plast Surg. Oct-Dec 1999;1(4):308-11. [Medline].
• Dinehart SM, Herzberg AJ, Kerns BJ, Pollack SV. Acne keloidalis: a review. J Dermatol Surg Oncol. Jun 1989;15(6):642-7. [Medline].
• George AO, Akanji AO, Nduka EU, et al. Clinical, biochemical and morphologic features of acne keloidalis in a black population. Int J Dermatol. Oct 1993;32(10):714-6. [Medline].
• Glenn MJ, Bennett RG, Kelly AP. Acne keloidalis nuchae: treatment with excision and second-intentionhealing. J Am Acad Dermatol. Aug 1995;33(2 Pt 1):243-6. [Medline].
• Gloster HM Jr. The surgical management of extensive cases of acne keloidalis nuchae. Arch Dermatol. Nov 2000;136(11):1376-9. [Medline].
• Goette DK, Berger TG. Acne keloidalis nuchae. A transepithelial elimination disorder. Int J Dermatol. Sep 1987;26(7):442-4. [Medline].
• Grunwald MH, Ben-Dor D, Livni E, Halevy S. Acne keloidalis-like lesions on the scalp associated with antiepilepticdrugs. Int J Dermatol. Oct 1990;29(8):559-61. [Medline].
• Herzberg AJ, Dinehart SM, Kerns BJ, Pollack SV. Acne keloidalis. Transverse microscopy, immunohistochemistry, and electronmicroscopy. Am J Dermatopathol. Apr 1990;12(2):109-21. [Medline].
• Jutley JK, Cunliffe WJ, Layton A, Wood EJ. Collagen chain composition and collagen gene expression in acne keloids. Biochem Soc Trans. Nov 1992;20(4):374S. [Medline].
• Kantor GR, Ratz JL, Wheeland RG. Treatment of acne keloidalis nuchae with carbon dioxide laser. J Am Acad Dermatol. Feb 1986;14(2 Pt 1):263-7. [Medline].
• Knable AL Jr, Hanke CW, Gonin R. Prevalence of acne keloidalis nuchae in football players. J Am Acad Dermatol. Oct 1997;37(4):570-4. [Medline].
• Layton AM, Yip J, Cunliffe WJ. A comparison of intralesional triamcinolone and cryosurgery in the treatment of acne keloids. Br J Dermatol. Apr 1994;130(4):498-501. [Medline].
• Pestalardo CM, Cordero A Jr, Ansorena JM, et al. Acne keloidalis nuchae. Tissue expansion treatment. Dermatol Surg. Aug 1995;21(8):723-4. [Medline].
• Sperling LC, Homoky C, Pratt L, Sau P. Acne keloidalis is a form of primary scarring alopecia. Arch Dermatol. Apr 2000;136(4):479-84. [Medline].

Article Last Updated: Apr 7, 2006