White prickly rash, known as crystal corn rash in Western medicine, is rare and occurs in patients with high fever and profuse sweating, weak infants and elderly people, commonly on the neck and trunk. The duration of the disease is short, usually about a week can be self-absorption crust and flaking and healing. What tests are needed to confirm the diagnosis of white heat rash? Check the time of occurrence, nature and color of the rash to diagnose prickly heat: 1, common in patients with high fever sudden sweating fever or a lot of sweating. 2. The rash mostly occurs on the trunk. 3. The rash is a pinhead-sized blister with thin and slightly shiny walls, clear and transparent herpes, and no redness around the blister. The wall of the blister is broken by light rubbing. After healing, there are very thin, fine scales. Therefore, the clinical examination for patients with white rash should be: i. Physical examination Taking a medical history gives us an initial impression and insight, and also guides us to have a concept of the nature of the disease. Laboratory examination Laboratory examination must be based on the history and physical examination of the objective material to summarize and analyze, from which several diagnostic possibilities are proposed, and then further consideration of those laboratory tests to confirm the diagnosis.