KERATOSIS PILIARIS

It is a common disorder,autosomal dominant

Seen in childhood and reaches its peak incidence

in adolescence.

keratinous plugs in the follicular orifices with

varying degrees of perifollicular

erythema.                                            

 

Clinical Picture:

The lesions appear as small gray to white plugs of

keratin that obstruct the mouths of the follicles

entrapping the hair.

sites of predilection: extensor surfaces of

the upper arms, thighs & buttocks.

except glabrous skin (like the palms

or soles of feet)

Treatments: may consist of moisturizing or

keratolytic treatments including: urea

, 

lactic acid, salicylic acid, or topical retinoids.

FOLLICULAR KERATOSIS(Lichen spinulosus)

  a disease of abnormal keratinization

appears in childhood.

The skin lesion presents with grouped follicular

papules occluded by a projecting keratinous spine.

Sites:extensor surface of the extremities,

thighs and abdomen.

DD: lichen planus ,seborrheic dermatitis.

Palmoplantar keratodermas

Its chronic thickening of palms and soles.

may be inherited (hereditary) or, more commonly,

acquired.

Hereditary keratoderma : runs in families, its Ad

or AR

Acquired keratoderma: occurs as a result of a

change in the health or environment

The genetic basis involves mutations in genes encoding

keratins, connexins, and desmosomal components.

Clinically, three distinct pattern : 1. Diffuse type : the whole palm and

sole, 2. focal type : are restricted to more

limited areas(mainly affect pressure areas)

3. punctate type : are bead-like tiny lesions

Complications: severe pain, difficulty in walking,

and secondary infection. Treatments: keratolytics and

systemic retinoids appropriate footwear is helpful.

Different skin diseases may give rise to palmoplanter hyperkeratosis

Psoriasis. Hyperkeratosis of the palms and soles with the silvery scales.

Reiter‘s disease Pityriasis rubra pilaris.. Eczema

Lichen planus Viral warts in immuno-compromised patients

may be confluent on the palms or soles. Hyperkeratosis due to dermatophytes (fungal

skin infections). Syphilis. Arsenic ingestion: causes multiple, irregular

warty keratoses