Pityriasis alba is an atopic dermatitis with hypopigmentation affecting children mostly on the face as white/pale spots and patches.
Pityriasis alba is chronic in nature and affects children of the age between 3 and 16 years. It is non-cancerous and appears as oval and round dry pale patches, especially on the children's cheeks. To start with the patches may be pink or red. Later the rash fades and gives a pale look with depigmentation in the affected areas.
These hypopigmented pityriasis alba patches appear oval and round, slightly erythematous and scaly. These spots usually affect the chin, cheek and mouth areas of the face of the kids. The border of the pityriasis alba rash is not clearly marked. The spots appear to blend gradually with the normal skin. On closer examination the affected area show whitish scales and hence is the name pityriasis alba (white scales).
The lesions are not completely depigmented. 50% of the kids are affected only on the face by these patches. These white areas are more noticeable in kids with dark or tanned skin. In addition to face in some cases these hypopigmented patches may involve neck, arms and shoulders of the affected kids. The trunk and legs are rarely involved in pityriasis alba afflictions.
The affected kids may show multiple lesions numbering even up to twenty, varying in size from 1 - 5 centimetres. Both sexes are affected and boys are more prone to develop it. In dark skinned kids the pale lesions are very prominent. Though the children are asymptomatic, their cosmetic appearance is of concern to parents.
These lesions do not tan. In the summer months the pityriasis lesions appear more prominent due to tanning of the surrounding skin. In winter and in dry climate the lesions flake. These pityriasis alba affected spots may remain for months or years and resolve after some period of time with the growth of children.