There are many clinical reasons for post-afternoon hypothermia, including pathological hypothermia: 1. Infectious diseases: such as viral infections, tuberculosis and other diseases. 2. Rheumatic immune diseases: such as systemic lupus erythematosus, rheumatoid arthritis and other rheumatic diseases. 3. Tumor diseases: such as lymphoma, leukemia and other hematologic tumors and liver cancer, intestinal cancer and other tumors can cause hypothermia. But many times it is not pathological hypothermia, there are also some normal physiological hypothermia: 1. High room temperature in the afternoon can also lead to the performance of hypothermia. 2. If the patient is menstruating, the body temperature can also appear to be appropriately elevated. 3. Problems with the thermoregulatory center during puberty can sometimes lead to persistent hypothermia. Therefore, when patients have symptoms of persistent hypothermia, they need to go to the infection department of a general hospital for examination and further diagnosis.