Vitiligo is a chronic skin disease that causes loss of pigment resulting in irregular pale patches of skin. 白斑是一种慢性疾病，致使缺少色素，使皮肤产生不规则的白色斑块。
Until now he had been too much ashamed of his pale and meagre body, with the varicose veins standing out on his calves and the discoloured patch over his ankle. 他的身体好生苍白消瘦，腿肚子青筋毕露，膝盖上长了白斑，这副德行，一直叫他免不了自惭形秽。
