The different shapes of temperature curves formed by routinely measuring the body temperature of a febrile patient and marking it on the temperature chart are known as heat patterns. Heat pattern is one of the manifestations of the interaction between pathogenic factors and the body, and many febrile diseases have a relatively specific heat pattern, so a typical heat pattern is valuable for disease diagnosis. Most of them are associated with primary illnesses that affect the body’s defense function, and there are more cases of hospital-acquired infections. Chills, high fever, and profuse sweating are more common in the bimodal fever pattern, and occasionally in the triphasic fever pattern, which is rare in sepsis caused by other pathogens and deserves attention. What is the cause of triple fever type? 1, drug-induced: anti-tumor drugs and immunosuppressants can directly kill proliferating cell populations, drugs inhibit or interfere with granulocyte nucleic acid synthesis, affect cell metabolism, and impede cell division. The direct toxic effects of drugs cause granulocyte reduction and drug dose related. Other drugs can also have direct cytotoxicity or reduce granulocyte production through immune mechanisms. 2, chemical toxins and radiation: chemical benzene and its derivatives, dinitrophenol, arsenic, etc. have toxic effects on hematopoietic stem cells, X-rays and neutrons can directly damage hematopoietic stem cells and bone marrow microenvironment, resulting in acute or chronic radiation damage and granulocytopenia. 3, immune factors: autoimmune granulocytopenia is the role of autoantibodies, T lymphocytes or natural killer cells in different stages of granulocyte differentiation, resulting in bone marrow damage, granulocyte production disorders. Commonly seen in rheumatic diseases and autoimmune diseases. 4, systemic infections: bacterial infections such as Mycobacterium bovis (especially Mycobacterium tuberculosis) and viral infections such as hepatitis virus, etc. 5, abnormal cell infiltration bone marrow: cancer bone marrow metastasis, hematopoietic system malignant disease and bone marrow fibrosis, etc. caused by the failure of bone marrow hematopoietic function. 6, cell maturation disorders – ineffective hematopoiesis: such as folic acid and vitamin B12 deficiency, affecting DNA synthesis, active bone marrow hematopoiesis, but cell maturation stagnation and destruction in the bone marrow. Certain congenital granulocyte deficiencies and acute non-lymphoblastic leukemia, myelodysplastic syndrome, and paroxysmal sleep hemoglobinuria also have maturation disorders that result in granulocytopenia.