Eczema craquelé, asteatotic dermatitis, is characterized by pruritic, dry, cracked, and polygonally fissured skin with irregular scaling.
Occurs most commonly on the shins of elderly patients.
May occur on the hands and the trunk.
Appears like cracked porcelain.
Suspected that epidermal water loss causes cracks disrupting dermal papillary capillaries with superficial hemorrhage and fissure formation.
Process may be associated with asymmetric leg edema, and increased lichenification that may occur with rubbing and scratching pruritic areas.
The eruptive process can be generalized or localized.
Generalized asteatosis suggests the possibility of associated systemic disease.
The localized form is divided into 4 types:
Asteatotic eczema of the lower extremities in elderly persons secondary to aging, dehydrated skin, and malnutrition.
Cracked erythema secondary to irritant contact dermatitis from soaps or detergents.
Eczema craquelé in areas in which corticosteroid therapy was discontinued.
Asteatotic eczema seen in neurologic disorders.
The process occurs when there is excess water loss from the epidermis results in dehydration of the stratum corneum, as the outer keratin layers require 10-20% water concentration to maintain their integrity.
In asteatotic dermatitis there is a significant decrease in free fatty acids in the stratum corneum resulting in an increase in transepidermal water loss up to 75 times that of healthy skin.
Stratum corneum lipids act as water modulators.
Astatotic eczema risk factors include: aging with decreased sebaceous and sweat gland activity, use of antiandrogen agents, use of degreasing agents, and bathing without replacing natural skin emollients lost to bath water.
When u the stratum corneum loses water it results in cell volume shrinkage, impairing skin elasticity and creating fissures.
Fissures rupture dermal capillaries and results in hemorrhage.
Underlying edema in the dermis leads to further stretching on the epidermis.
Fissures rupturedermal capillaries, causing clinical bleeding.
The disruption of cutaneous integrity in asteotic dermatitis can result in inflammation and risk of infection.
Because of transepidermal absorption of allergens and irritants is increased as the epidermis is damaged, increasing susceptibility to allergic contact dermatitis and irritant contact dermatitis occurs.
Allergic contact dermatitis and irritant contact dermatitis may cause a persistent and more extensive dermatitis as a result.
Low environmental humidity contributes to the process, and most patients present in the winter months.
Most cases resolve without sequela.
Can be a chronic process with relapses frequent during the winter months and during times of low humidity.
More common in men than women, with a median age of 69 years at presentation
Can occur in young people.
Characteristically an elderly person presents during winter months with pruritic and dry skin with dermatitis on the pretibial areas.
Dysesthesia may be present and described as a pinprick or biting sensation.
Excoriated, erythematous, and edematous patches may result from rubbing or scratching of the lesions.
Causes include: xerosis, frequent hot bathing, use of soap, infrequent use of emollients, use of degreasing agents, solvents, cleansers, decreasing sweating due to age, essential fatty acid deficiency, atopy, ichthyosis, thyroid disease, diseases with diminished sweat and sebaceous gland activity, antiandrogen therapy, diuretic therapy, and malignancies.
Management includes the taking of short baths with decreased water temperature, eliminating or reduce the use of soap, avoiding harsh skin cleansers, applying petrolatum-based emollients following bathing, using moisturizers, applications of topical steroid ointments, and use of humidifiers.
The use of topical steroid ointments with occlusion or Unna boots are the treatment of choice for the rapid resolution of asteatotic dermatitis.
Unna Boots can be left intact usually for 3-5 days.
Many patients heal with topical steroids alone.
Moisturizers, especially those petrolatum- based, with topical steroids recommended.
Hydrating the skin followed by steroid ointment daily clears more than 90% of cases you 4-14 days.
While asteatotic dermatitis responds well to therapy, recurrences are common.