Keratosis pilaris

Skin | Dermatology | Keratosis pilaris (Disease)


Description

Keratosis pilaris (KP) is a genetic disorder of keratinization of hair follicles of the skin. It is an extremely common benign condition that manifests as small, rough folliculocentric keratotic papules, often described as chicken bumps, chicken skin, or goose bumps, in characteristic areas of the body, particularly the outer-upper arms and thighs. Although no clear etiology has been defined, keratosis pilaris is often described in association with other dry skin conditions such as ichthyosis vulgaris, xerosis, and, less commonly, with atopic dermatitis, including conditions of asthma and allergies.

Keratosis pilaris affects nearly 50-80% of all adolescents and approximately 40% of adults. It is frequently noted in otherwise asymptomatic patients visiting dermatologists for other conditions. Most people with keratosis pilaris are unaware the condition has a designated medical term or that it is treatable. In general, keratosis pilaris is frequently cosmetically displeasing but medically harmless.

Overall, keratosis pilaris is described as a condition of childhood and adolescence. Although it often becomes more exaggerated at puberty, it frequently improves with age. However, many adults have keratosis pilaris late into senescence. Approximately 30-50% of patients have a positive family history. Autosomal dominant inheritance with variable penetrance has been described.

Seasonal variation is sometimes described, with improvement of symptoms in summer months. Dry skin in winter tends to worsen symptoms for some groups of patients. Overall, keratosis pilaris is self-limited and, again, tends to improve with age in many patients. Some patients have lifelong keratosis pilaris with periods of remissions and exacerbations. More widespread atypical cases may be cosmetically disfiguring and psychologically distressing.

Causes and Risk factors

Keratosis pilaris results from the buildup of keratin — a hard protein that protects the skin from harmful substances and infection. The keratin forms a scaly plug that blocks the opening of the hair follicle. Usually many plugs form, causing patches of rough, bumpy skin. Why keratin builds up is unknown. But it may occur in association with genetic diseases or with other skin conditions, such as ichthyosis vulgaris or atopic dermatitis. Keratosis pilaris also occurs in otherwise healthy people. Dry skin tends to worsen this condition.

Diagnosis and Treatment

There is no laboratory test or skin test commonly used to diagnose keratosis pilaris. Instead, its typically diagnosed based on an examination of the skin and a review of the medical history. Thedoctor will ask questions about the signs and symptoms. No single treatment universally improves keratosis pilaris. Most options, including self-care measures and medicated creams, focus on softening the keratin deposits in the skin. ...