Atopic Dermatitis Eczema

Question 1

Definition

Answer 1

Common inflammatory skin condition characterised by dry, pruitic skin with a chronic relapsing course.

Question 2

Pathophysiology

Answer 2

Defects in the skin barrier layers causes gaps which provide entrance for irritant, microbes and allergens triggering an immune response resulting in inflammation and associated symptoms.

Question 3

Risk factors

Answer 3

• History of atopy
• Family history of eczema and mutation of the - FLG gene (encodes for filaggrin which is a protein required for effective skin barrier)

Question 4

Signs

Answer 4

Pruitus
Xerosis (dry skin)
Scaly and erythematous
In darker skin = brown/grey
Commonly affects flextures = elbows, knees, and wrists)

Question 5

Diagnosis

Answer 5

Clinical diagnosis
IgE levels (high), skin prick testing
Divided into mild, moderate and severe

Question 6

Treatment

Answer 6

Removal of identified precipitating factors
Mild: mild potency topical cortico-steroids + emoliants e.g. water-based diprobase or E45
Mod: emoliants + mod potency topical corticosteroids, topical calcineurin inhibitors (tacrolimus) and bandages
Severe: all above + photo therapy + systemic therapy (oral corticosteroids, methotrexate, and azathioprine)

Question 7

Bacterial skin infections

Answer 7

Common in eczema due to breakdown in the skin barrier
MC organisms = staphylococcus aureus + treated with flucloxacillin
HSV can cause eczema herpeticum = treated with aciclovir