Whether high fever platelet 50 is serious or not depends on the cause of the condition, which varies in severity depending on the cause. High fever platelet 50 is mostly caused by infectious diseases, hematologic diseases and so on. 1. Infectious diseases: Bacterial and viral infections can lead to fever, which is the body’s normal response to fight pathogens. If bacteria and viruses invade the bone marrow, they will continue to produce toxins, impairing the ability of megakaryocytes to proliferate and mature, leading to a decrease in platelet production. After anti-infection treatment, body temperature and platelets will return to normal. 2. Blood system diseases: Acute leukemia will lead to thrombocytopenia, reduced immunity of the body, easy to cause infections, which can be manifested as fever, bleeding from the skin and nasal cavity, anemia and so on. Chemotherapy is needed and platelet transfusion if necessary. Blood system diseases are more serious and should be taken seriously. If the above symptoms occur, it is recommended to go to the hospital in time for early and regular treatment.