Ichthyosis vulgaris is an autosomal dominant form of ichthyosis, and is divided into blistering and non-blistering forms. The blister type shows flushing all over the body, with herpes and large epidermal peeling, and the newly formed keratin layer on the peeling surface, covered with large gray-brown scales in the shape of warts. The non-blistering type shows thickened skin keratinization, with the child’s entire body red and wrapped in a thick keratinous membrane, like fire cotton glue, which is removed to leave the red skin and appear as thick scales. So what is the differential diagnosis of ichthyosis vulgaris-like erythroderma? Here is a brief introduction. 1, sex chain occult ichthyosis: can be after birth or infant onset, lesions scales large and prominent, yellow-brown or black large fish scales, dry and rough skin, often all over the body, the axilla, and elbow fossa and other parts can also be involved; abdomen, back, especially heavy, such as facial involvement, is limited to the front of the ear and the side of the face, generally does not occur follicular keratinization, palm toe skin normal, lesions do not reduce with age, and sometimes increased. Sometimes it is heavier. 2.Epidermolysis bullosa hyperkeratosis ichthyosis: also called herpetic congenital ichthyosis-like erythrodermatosis: it is an autosomal dominant genetic disease with high aberration rate, it is rare clinically, after birth or a few months after birth, there can be generalized and situation-limited damage, when generalized, there is armor-like thick layer of scaly nails all over the body at birth, it is shed after birth, there is generalized flushing and scaling, peel off the scales to present moist surface, the red spots can gradually disappear, it can be re The erythema can gradually disappear, and thicker warty scales can occur again, the situation limited person can only have thicker fish scale keratinous flakes in the flexural side of the limbs and wrinkled wall.