This document discusses a common skin disorder characterized by keratinous plugs in hair follicles. It typically appears in childhood and adolescence on the extensor surfaces. The lesions appear as small gray or white plugs that obstruct hair follicles. Treatments include moisturizers and keratolytic agents. The document also discusses palmoplantar keratoderma, a thickening of the palms and soles that can be inherited or acquired, and presents in three patterns: diffuse, focal, or punctate. Complications can include pain, difficulty walking, and infection.

2.  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.

3. 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)

4.  Treatments: may consist of moisturizing or
keratolytic treatments including: urea,
lactic acid, salicylic acid, or topical retinoids.

5.  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.

6.  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

7.  The genetic basis involves mutations in
genes encoding
 keratins,
 connexins, and
 desmosomal components.

8. 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

10. Complications:
 severe pain, difficulty in walking, and
secondary infection.
 Treatments: keratolytics and systemic
retinoids
appropriate footwear is helpful.

11. 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

12.  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