1. ����ʡ����Ԥ����������
2. �й�ҽѧ��ѧԺ����Э��ҽѧԺƤ�����о��������
3. �Ͼ� �й�ҽѧ��ѧԺ����Э��ҽѧԺƤ�����о���

��ժҪ�� ����������һ�ַ����ڶ�ͯ�ľ�����ɫ�ؼ����Լ���������΢��м���߽粻�塣�䷢�������в��������Ӧ�����ʡ����Ｐ�չ�������DZ�ڵ�Σ�����ء���֯������ʾ�����������Ƥ���ײ���غ�����Ƥ����Χ����Ƥ�������Լ��٣������黯��ʾ����������Ƥ���ײ����ϸ��������Ƥ����Χ����Ƥ��������ͳ��ѧ���塣�����п���ʹ����������½��о���ʾ���Ƶ�����ø���Ƽ��ȿ���ҩ����������õ����Ƽ�Ԥ����������Ч��

Bao Youhong*�� Chang Litao, Zhang Wei, Jiang Yiqun. *Yunnan Center for Disease Control and Prevention, Kunming 650032, China Corresponding author: Zhang Wei, Email��ifmtjoel@163.com ��Abstract�� Pityriasis alba, a skin disorder mostly occurring in children, is characterized by localized hypopigmented, slightly scaling patches with indistinct margins. The etiology of pityriasis alba is not well established. Atopy, xerosis, and sun exposure are potential risk factors for it. Histopathologically, there is a marked reduction in epidermal melanin content in lesional skin compared with perilesional normal skin, but immunohistochemical studies show no significant difference in the number of melanocytes between lesional and perilesional skin. It may be treated with lubricants and emollients. Recent studies have shown that anti-inflammatory drugs, such as calcineurin inhibitors, exhibit favorable efficacy in treating and preventing the recurrence of pityriasis alba.