Pemphigus vulgaris in small children is mostly related to genetic, autoimmune, neuropsychiatric, infection and other factors. 1. Heredity: the occurrence of baldness has a certain genetic basis, parents who have a history of baldness, their children have an increased risk of baldness. 2. Autoimmune: If the child’s autoimmune abnormalities, when the local hair follicle immune immunity mechanism is destroyed, it will induce pemphigus vulgaris. Pemphigus vulgaris can be complicated by vitiligo, dry syndrome and other autoimmune diseases. 3. Nervousness and spirituality: if the child has a long time of mental stress, it can induce baldness, such as nervousness, depression, anxiety, insomnia and so on. 4. Infection: Patchy baldness can also occur after fungal infection, herpes zoster, syphilis and other diseases. Once a child is diagnosed with baldness, parents need to bring the child to the hospital and actively take relevant treatment measures.