Platelet 454 does not indicate the severity of the disease, and should be combined with clinical manifestations and other tests to make a comprehensive judgment. The normal value of platelets is (100-300) × 10^9/L. Platelet 454×10^9/L indicates thrombocytosis, which can be seen in reactive thrombocytosis (e.g. acute and chronic inflammation, iron deficiency anemia, acute hemolysis, certain cancers, etc.), myeloproliferative disorders (e.g. primary thrombocythemia, true erythrocytosis, chronic myelogenous leukemia, and early stage of primary myelofibrosis, etc.). If only platelets 454×10^9/L, it does not indicate whether it is serious or not, but also needs to be combined with clinical manifestations and other test results to comprehensively determine the severity of the disease. It is recommended to go to the hospital in time to identify the cause of the disease and then targeted treatment.