Pityriasis alba
- Pityriasis alba is a low-grade type of eczema/dermatitis mainly seen in children 3-16 years.
- form of subacute atopic dermatitis
- very common mild condition, worse in summer (b/c won’t tan) & dark skinned children
- self limiting and will clear up in months, sometimes years
- diagnosis
- rule out other causes of pigmentation
- Wood lamp examination: the hypopigmentation of pityriasis alba does not enhance, and there is no fluorescence
- Scrapings for mycology: microscopy and fungal culture are negative in pityriasis alba
- Skin biopsy: biopsy is rarely required, but may reveal mildly spongiotic dermatitis and reduction in melanin.
- rule out other causes of pigmentation
- mx: non-soap cleanser, emollients. Hydrocortisone rarely needed or pimecrolimus
Treatment
No treatment is necessary for asymptomatic pityriasis alba.
- A moisturising cream may improve the dry appearance.
- A mild topical steroid (0.5-1% hydrocortisone) may reduce redness and itch if present.
- Calcineurin inhibitors (pimecrolimus cream and tacrolimus ointment) may be as effective as hydrocortisone and have been reported to speed recovery of skin colour.