Autoeczematisation

What is autoeczematisation?

Autoeczematisation is an acute, generalised skin reaction to a variety of stimuli. This stimulus may be a pre-existing or new dermatitis (most often on the lower leg), or skin infection with fungi, bacteria, viruses or parasites. The rash tends to occur at a site distant from the original infection or dermatitis.

Autoeczematisation is also known as Id reaction and autosensitisation.

Autoeczematisation

Why does it occur?

The exact cause of autoeczematisation is unknown. It is thought to be a disorder of the body's immunological response to the original ailment. A worsening of a pre-existing dermatitis caused by infection, scratching or inappropriate treatment often precedes autoeczematisation. Possible risk factors for the condition include recent skin rash or infection, a medical history of allergies, and stress.

What are the clinical features?

Signs and symptoms vary according to the original ailment that triggers autoeczematisation but may include:

• Varying degrees of itching
• Sudden, itchy, symmetrical red rash occurring at least one to two weeks after the primary skin infection or dermatitis (sometimes months or even years later)
• Variable rash: may be small raised spots, large red flat patches, or pus-filled vesicles (small blisters)

Autoeczematisation with gravitational eczema is the most common form. The reaction usually involves the forearms, thighs, legs, trunk, face, hands, neck and feet (in descending order of frequency).

What treatment is available?

The main aim of treatment is to correct the initiating skin infection or dermatitis.

Autoeczematisation usually resolves once the original ailment is appropriately treated. Acute outbreaks of autoeczematisation can be treated with systemic or topical corticosteroids and wet compresses.