Leg dermatitis

Learning objectives
Classification
Venous dermatitis
Asteatotic dermatitis
Differential diagnosis
Management
Activity

Learning objectives

• Classify and manage dermatitis affecting the leg

Classification

Dermatitis exclusively or predominantly affecting legs may be due to:

• Venous stasis
• Varicose veins
• Asteatosis
• Contact factors
  • Irritants
  • Allergens
• Constitutional factors
  • Atopic dermatitis
  • Nummular dermatitis
  • Prurigo

Venous stasis

Normally during walking the leg muscles pump blood upwards and valves in the veins prevent pooling. Deep venous thrombosis or varicose veins may damage the valves resulting in oedema, particularly after prolonged standing and during hot weather.

Dermatitis due to venous disease (also known as ‘stasis eczema’ and ‘gravitational dermatitis’) can arise as discrete patches or affect the leg circumferentially. The affected skin is red and scaly, and may ooze, crust and crack. It is frequently itchy. Irregular haemosiderin pigmentation is usually present.

Common complications include:

• Impetiginisation
• Cellulitis
• Autosensitisation dermatitis (autoeczematisation)
• Lichenification
• Lipodermatosclerosis (panniculitis): woody induration
• Atrophie blanche: white scarred areas surrounded by capillary ectasia
• Ulceration, frequently over the medial malleolus and provoked by a minor injury
• Contact allergy to one or more components of topical treatment

Venous eczema

Varicose veins

Varicose eczema is a variant of nummular dermatitis in which discrete patches of dermatitis overlie varicose leg veins.

Varicose eczema

Asteatotic eczema

Ateatotic eczema presents as dry discoid eczema and is found most often on one or both lower limbs. Eczema craquelé refers to ‘crazy paving’ appearance.

Asteatotic eczema

Differential diagnosis

Psoriasis is the most common skin condition that may be confused with dermatitis on the lower legs. Other conditions to be considered in this site include:

• Insect bites
• Cellulitis
• Hypertrophic lichen planus
• Ichthyosis
• Livedoid and other forms of vasculitis
• Capillaritis
• Disseminated superficial actinic porokeratosis

Management

Advise the patient to reduce swelling:

• Don't stand for long periods
• Take regular walks
• Elevate feet when sitting or lying
• Wear graduated compression stockings long term
• Take care to minimise trauma and consult a doctor if injury arises.

Management of the dermatitis requires wet dressings for acute blistering; emollients, especially if there is eczema craquelé; intermittent topical steroids; and oral antibiotics.

Seek the opinion of a vascular surgeon regarding value of eradicating varicose veins.

Activity

Describe the selection and use of compression hosiery.

 

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