Keratosis pilaris (and its variants)

Patient Information Leaflet
Link: Keratosis pilaris

https://pcds.org.uk/patient-info-leaflets/keratosis-pilaris

Keratosis pilaris (KP) is a very common skin condition characterised by keratinous plugging of hair follicles, with varying degree of perifollicular erythema, most commonly affecting the outer-upper arms and thighs.

This chapter is set out as follows:

• Keratosis pilaris is due to abnormal keratinisation of the lining of the upper portion of the hair follicle, known as the follicular infundibulum - scale fills the follicle instead of exfoliating
• Mild forms, appearing in childhood and adolescence, are extremely common and are best regarded as physiological
• 30-50% of cases have genetic origins, with an autosomal dominant inheritance
• Associated conditions include other dry skin conditions such as ichthyosis vulgaris, obesity, insulin-dependent diabetes mellitus, and Down's syndrome

• KP is best described as a condition of childhood and adolescence, and although it often becomes more exaggerated at puberty, it frequently improves with age. However, some adults can have rather persistent KP
• Seasonal variation is sometimes described, with improvement of symptoms in summer months 
• Lesions are asymptomatic

Typical KP

• Symmetrical, most commonly affecting the outer-upper arms and thighs
• KP may also occur on the buttocks and cheeks, and less often on the forearms and upper back
• Large numbers of scaly, rough papules, which in essence is the keratinous plugging of hair follicles
• Varying degrees of perifollicular erythema 

Atypical KP

• Has more widespread involvement of the skin, which may cause psychological distress  

Erythromelanosis follicularis faciei et colli

• Is very rare, mainly seen in Asian men, and probably represents a variant of KP in pigmented skin
• Clinically there is follicular plugging, erythema and hyperpigmentation of the cheeks and neck 

KP associated with atrophy

KP is occasionally followed by atrophy, with scar-like follicular depressions and sometimes hair loss - such features can be associated with more typical KP at other sites: 

• Keratosis rubra pilaris faciei atrophicans (syn. ulerythema ophryogenes): prominent facial erythema with involvement of the eyebrows and scalp, followed by atrophy 

• Atrophoderma vermiculatam: keratotic papules of the cheeks and pre-auricular skin are followed by atrophy

• Provide a patient information leaflet on keratosis pilaris

• No cure is available for KP and treatment is rarely helpful:

• Female patients, in particular, may wish to try facial exfoliators with a buff for their arms and legs

• Emollients containing urea (eg Calmurid ® cream, Balneum ® cream) or salicylic acid can be used 

• Mild topical steroids (eg Eumovate ® cream) may be used BD for a few days, eg prior to an important social occasion, to reduce redness in those with a very significant perifollicular erythema. Topical steroids must not be used regularly in KP as they may cause skin atrophy