What symptom characterizes acute myeloid leukemia (AML)?

Acute myeloid leukemia (AML) is characterized by the rapid proliferation of myeloid cells, which can lead to an overall decrease in normal blood cell production, a condition known as pancytopenia. This results in lower levels of red blood cells, white blood cells, and platelets in the bloodstream. Clinically, patients may present with symptoms related to anemia (fatigue, pallor), increased risk of infection due to leukopenia, and bleeding tendencies related to thrombocytopenia.

In contrast, elevated white blood cell count, while it can be present in some forms of leukemia, is not a consistent feature across all cases of AML. Thrombocytosis, which indicates an increased platelet count, is typically not associated with AML; instead, patients often experience thrombocytopenia. Lymphadenopathy, or swollen lymph nodes, can occur in various hematological malignancies but is not a primary symptom of AML specifically. Thus, pancytopenia is the most characteristic symptom of AML due to the effects of the disease on normal hematopoiesis.