A persistent low fever does not necessarily mean leukemia. There are many reasons why a low fever may not go away, such as the most common recurrent bacterial infections, which can occur if not symptomatic, and some viral infections, tuberculosis, and tumor patients, all of whom may have a low fever. For patients who have a low fever that does not go away, it is best to go to the hospital for routine blood tests and other tests to clarify the cause. There are some patients with leukemia who can show a low fever, but a low fever does not necessarily mean leukemia, and the incidence of leukemia is not that high after all, so it is important to go to the hospital for a full examination of the low fever. There are also some reasons why a low fever may be a connective tissue disease, especially for some young and middle-aged patients, or some elderly people, if a low fever does not go away it may also be a connective tissue disease, but if it is a recurring long-term low fever to the hospital for examination, when acute leukemia is suspected, the diagnosis needs to be confirmed by further bone marrow aspiration. If it is really acute leukemia, or chronic leukemia, it should be treated according to these causes.