What symptoms are present that warrant suspicion of hemophagocytic syndrome? Symptoms such as fever and hepatosplenomegaly are seen in many hematologic disorders, so what are the conditions that warrant consideration of phagocytic syndrome? The clinical manifestations of phagocytic syndrome are diverse, such as hepatosplenomegaly, fever, and allogeneic cytopenia, and there are no specific symptoms. Moreover, the symptoms of primary and secondary phagocytic syndrome are different. In fact, to diagnose primary phagocytic syndrome, the patient’s family genetic history and genetic testing are important to consider the disease even if the symptoms are atypical. Foreign reports suggest that atypical diarrhea may be an early symptom of primary phagocytic syndrome, so for people with a family history or whose first baby had phagocytic syndrome, it is important to be on high alert for primary phagocytic syndrome when mild atypical diarrhea symptoms are present. Phagocytic syndrome is highly suspected when a patient meets the following three symptoms: first, unexplained fever, such as fever for one or two weeks, but no foci of bacterial infection can be found and no infecting virus can be found; second, unexplained liver function impairment, i.e., abnormal liver function is present, but no specific cause can be found; third, unexplained hematocrit, such as the presence of anemia, decreased white blood cells, platelets After various bone marrow aspiration and other tests still cannot determine which hematologic disorder is the cause. When a patient meets the above three symptoms, it is recommended to see a specialist in hemophagocytic syndrome or a specialist in hematology as soon as possible to conduct laboratory tests and make a diagnosis.