Description

Small (1 to 2 mm), keratotic papules are localized to hair follicles, most frequently on the lateral aspects of the arms and thighs; often described as chicken skin or goose bumps

Epidemiology

There is a slight female predominance.

Prevalence
KP affects up to 80% of adolescents, often worsening during puberty, and up to 40% of adults.

Etiology and Pathophysiology

• The abrasive (“sandpaper-like,” “chicken skin–like,” or “goose bump–like”) texture of the skin is caused by excess buildup of keratin. An underlying hair may be found in some of the papules. In the inflammatory variant, mild perifollicular erythema is present.
• Autosomal dominant inheritance, with incomplete penetrance. KP is more frequent in obese patients.

Genetics
Autosomal dominant inheritance, with incomplete penetrance and variable expressivity, has been described, and many (30–50%) will report a positive family history of the disorder.

General Prevention

Moisturize to prevent excessive drying of the skin. Use only mild soaps (cleansers). Avoid hot showers.

Commonly Associated Conditions

Ichthyosis, xerosis, atopic dermatitis