Paediatrics: Pustular rashes

Pustular rashes

Generalized pustulosis is unusual. When the child is <2yrs, immunode-ficiency, particularly phagocyte dysfunction, should be excluded. Local causes in older children include:

·  acne vulgaris;

·  folliculitis;

·  impetigo;

·  scabies;

·  perioral dermatitis;

·  pustular psoriasis.

Acne vulgaris

Acne affects 90–100% of teenagers. However, acne may occur in neo-nates (spontaneous improvement without treatment occurs), infant (often requires treatment and may imply severe acne in later years) and adult (often women older than 25).

Cause

Excess sebum production, hyperkeratosis of the hair follicle, Propionibacterium acnes bacterial proliferation and inflammation of the hair follicle lead to acne.

Hyperandrogenism should be suspected if—acne is severe, sudden and of early onset; if there are other signs of hyperandrogenism including irreg-ular periods, hirsuitism, male or female pattern hair loss and deepening of the voice in women; or there is treatment resistance.

Diet has not yet been proven to impact acne, but a healthy diet and exercise are recommended.

Presentation

Inflammatory (papules, pustules and nodules and cysts) and comedonal (blackheads and whiteheads) acne. There may be hypertrophic and/or atrophic scarring. Acne may affect the face, back, and chest.

Treatment

·  General measures:

·  use a gentle soap free cleanser daily;

·  use oil free and non-comedogenic make-up.

·  Specific measures:

·  topical retinoids for comedonal acne, e.g. adapalene, tretinoin;

·  topical antibiotics for inflammatory acne, e.g. clindamycin;

·  topical benzoyl peroxide 2.5–5% for inflammatory acne;

·  oral antibiotics for inflammatory acne, e.g. erythromycin, tetracyclines;

·  oral isotretinoin if severe or unresponsive to above (side-effects: teratogenic, avoid in teenage pregnancy; headaches; myalgia; dry skin/mucous membranes; sun photosensitivity).

Prognosis 

Resolves, but may persist for years in some cases. Psychological support is important.