Dyskeratotic disorder Elloisa Grace Ganaden MD Dyskeratotic disorder

Subtopics Keratosis Pilaris Callosities Calus Knuckle Pads Keratoma of palms and soles

Dyskeratosis abnormal keratinization occurring prematurely within individual cells or groups of cells below the stratum corneum.

Keratosis pilaris (KP, also follicular keratosis, lichen pilaris or chicken skin) is a common, autosomal dominant, genetic follicular condition extremely common benign condition manifested as small, rough, slightly red, folliculocentric keratotic papules/ bumps on the skin. It most often appears on the back and outer sides of the arm (though the forearm can also be affected), and can also occur on the thighs, hands, and tops of legs, sides, buttocks, or any body part except glabrous skin (like the palms or soles of feet).

Pathophysiology Genetically based disorder of hyperkeratinization of the skin. Excess formation of keratin is cause abrasive goose-bumps texture of the skin. condition most often appears as a proliferation of tiny hard bumps that are seldom sore or itchy.

Clinical presentation: HX: px report a rough texture (gooseflesh apperance) PE: skin of the outer-upper arms and thighs is frequently affected. 10-100 very small, slighlty red rough bumps scattered in area. palpation reveal a fine, sandpaper like texture.

DDX Acne vulgaris Atopic dermatitis Folliculitis milia

Types of KP >keratosis pilaris rubra - red, inflamed bumps which can be on arms, head, legs >keratosis pilaris alba - rough, bumpy skin with no irritation. >keratosis pilaris rubra faceii - reddish rash on the cheeks.

Treatment moisturizing or keratolytic treatments including: urea, lactic acid, salicylic acid, or topical retinoids.

Callus (Callosity) is a toughened area of skin which has become relatively thick and hard in response to repeated friction, pressure, or other irritation. repeated contact is required, most often found on feet. generally not harmful, but may sometimes lead to other problems, such as skin ulceration or infection.

Corn(clavus,clavi) Heloma >specially-shaped callus of dead skin that usually occurs on thin or glabrous (hairless and smooth) skin surfaces, especially on the dorsal surface of toes or fingers. They can sometimes occur on the thicker palmar or plantar skin surfaces. Corns form when the pressure point against the skin traces an elliptical or semi-elliptical path during the rubbing motion, the center of which is at the point of pressure, gradually widening.

pathophysiology The bony prominences of the metacarpophalangeal and metatarsophalangeal joints often are shaped in such a way to induce overlying skin friction.(perpetuate hyperkeratosis)

Hard corns(heloma darum)- occur on dry, flat surfaces of skin. Soft corns (heloma molle)- frequently found between adjacent toes, stay moist, keeping the surrounding skin soft.

Clinical presentation HX: faulty mechanics; inappropriate distribution of pressure and repetitive motion injury PE: lesion look like hyperkeratotic or thick skin, maceration and secondary fungal or bacterial infection are comon

Treatment Calluses and corns may go away by themselves eventually, once the irritation is consistently avoided. They may also be dissolved with keratolytic agents containing salicylic acid, sanded down with a pumice stone or filed down with a callus shaver.

KNUCKLE PADS benign, asymptomatic, well-circumscribed, freely movable, skin-colored, wartlike, solitary or multiple nodules and plaques up to 40 mm in diameter located in the skin overlying the dorsal aspects of the hands and feet.

Pathophysiology Idiopathic, genetic, acquired as a response to repetitive trauma.

Clinical presentation Hx: asx, firm skin-colored papules appear sequentially in multiple sites overlying MCP and PIP joints in hands. PE: well circumscribed firm dermal papules, nodules or plaque approx 0.5-3cm in size located extensor aspect of PIP or MCP joints.

DDX Erythema elevatum diutinum Granuloma annulare xanthomas

treatment Eliminating the source of mechanical or repetitive trauma may improve the lesions. IL of corticosteroids Keratolytics Radiation therapy and application of solid CO2

Palmoplantar Keratodermas Autosomal recessive and dominant, heterogeneous group of disorders characterized by abnormal thickening of the palms and sole. Divided: -acquired -inherited

Inherited: 3 distinct clinical pattern of epidermal involvement.

3 distinct clinical patterns: 1.diffuse PPK- uniform involvement of the palmoplantar surface. - this pattern is usually evident within the first few months of life. 2. focal PPK - consists of localized areas of hyperkeratosis located mainly on pressure points and sites of recurrent friction. 3. punctate keratoderma - features multiple small, hyperkeratotic papules, spicules, or nodules on the palms and soles. -this tiny keratoses may involve the entire palmoplantar surface or may be restricted to certain locations (eg, palmar creases).

Treatment and management The most common therapeutic options only result in short-term improvement and are frequently compounded by unacceptable adverse effects. Treatment tends to be symptomatic and may vary from simple measures - saltwater soaks , topical keratolytics, systemic retinoids, or reconstructive surgery with total excision of the hyperkeratotic skin followed by grafting.

Mainstay treatment Topical keratolytics (eg, salicylic acid 5%, lactic acid 10%, urea 10-40%) are useful in patients with limited keratoderma. Topical retinoids (eg, tretinoin) are effective, but treatment is often limited by skin irritation. Consider potent topical steroids with or without keratolytics in dermatoses with an inflammatory component. Oral retinoids are effective

Mainstay treatment: Psoralens and ultraviolet A (PUVA) or re-PUVA (a combination of oral retinoids and PUVA) may be indicated in persons with PPK secondary to psoriasis or eczema. Patients with oculocutaneous tyrosinemia may benefit from dietary restriction of phenylalanine and tyrosine. Careful selection of footwear and treatment of fungal infections are important. Dermabrasion may permit increased penetration of topical agents, and carbon dioxide laser treatment may be beneficial in persons with limited keratodermas.

Mainstay treatment: For severe and refractory keratoderma, consider surgery. Total excision of hyperkeratotic skin followed by grafting has been successful in a number of cases. Paraneoplastic keratodermas are generally refractory to local treatment and may only respond to removal of the underlying neoplasm.