异食癣是指患儿好吃一些非食物性东西如:泥土、墙皮、煤渣、纸片、烟头,火柴、沙子、手指甲等,有的还喜欢闻某种特殊气味。此种小儿多表现出食欲低下,偏食及营养发育状况低下、贫血等.通常好发年龄为1～3岁,也可达学龄前期。从前认为由肠道寄生虫引起,但很多病人驱虫治疗症状并不消失. Xanthotic ringworm refers to the children to eat some non-food stuff such as: soil, plaster, cinder, paper, cigarette butts, matches, sand, fingernails, etc., and some also like to smell a special smell. Such children show low appetite, partial eclipse and nutritional development is low, anemia, etc. Usually good hair age of 1 to 3 years old, but also reach the pre-school age. It was previously thought to be caused by intestinal parasites, but the symptoms of deworming treatment in many patients did not disappear.