Children appear to have a fever after the phenomenon of erythema on the body, the first check blood routine, coagulation function, C-reactive protein, to confirm the diagnosis of erythema type, according to the type of targeted treatment. The most common disease is rash, often caused by viral infection, treatment is mainly the use of antiviral drugs. For the phenomenon of rash, it is recommended to apply local glycerin lotion to stop itching. If there is no itching, you can not touch the red spots. Fever-reducing drugs are needed during fever, especially when the temperature is greater than 38.5 degrees. If the coagulation function and platelet abnormality, the treatment is more complicated, first need to go to the hematology department to do bone marrow aspiration to confirm the type of blood disease, to find out the cause of the abnormal coagulation function for targeted treatment, the effect is better.