Nevus Comedonicus

Nevus comedonicus is also known as comedo nevus, nevus follicularis keratosis, nevus acneiformis unilateralis, and nevus zoniforme. Nevus comedonicus is a rare hamartoma of the pilosebaceous unit. Clinically, comedo-like dilated pores with keratinaceous plugs present in a linear, nevoid, bilateral, or zosteriform pattern . An inflammatory variant also exists, with suppurative cysts and acne-like lesions. These lesions appear on the face, chest, or upper arms at birth or during childhood. Nevus comedonicus syndrome is the association of nevus comedonicus with non-cutaneous findings such as skeletal defects, cerebral abnormalities, and cataracts.

NEVUS COMEDONICUS AT A GLANCE

· Presents as comedo-like dilated pores with keratinaceous plugs; linear, nevoid, bilateral, or zosteriform pattern.

· Nevus comedonicus syndrome: Association of nevus comedonicus with non-cutaneous findings such as skeletal defects, cerebral abnormalities, and cataracts.

· Hallmark findings: Keratin-filled epidermal invaginations associated with atrophic sebaceous glands or follicles.

· Differential diagnosis: Acne vulgaris, acne neonatorum, milia nevus sebaceous, linear Darier disease.

· Inflammatory variant can result in significant suppuration and pain, requiring medical or surgical intervention.

COURSE AND COMPLICATIONS

Nevus comedonicus lesions follow a noninflammatory or inflammatory course and do not resolve spontaneously. The inflammatory course may result in scarring. Nevus comedonicus syndrome results in developmental, cerebral, skeletal, or ocular defects that present by the age 15 years.

PATHOLOGY

The hallmark findings in nevus comedonicus are keratin-filled epidermal invaginations associated with atrophic sebaceous glands or follicles. EHK may be seen.

DIFFERENTIAL DIAGNOSIS

The differential diagnosis of this lesion includes acne vulgaris, milia, acne neonatorum, nevus sebaceous, and linear Darier disease.

TREATMENT

The noninflammatory variant of nevus comedonicus is usually asymptomatic, with treatment based on the cosmetic concerns of the patient. The inflammatory variant can result in significant suppuration and pain, requiring medical or surgical intervention. Inflammation may be controlled with tazarotene cream or other retinoids, tacrolimus ointment, calcipotriene cream, and intralesional steroids. Keratolytics may be of some help. Systemic antibiotics may help to control infection or inflammation. Surgical interventions, such as extraction, excision, dermabrasion, or laser resurfacing, may result in good clinical results