It may reveal both an excess of white blood cells (leukocytosis) or a decrease (leukopenia), and a low red blood cell count (anemia) and low platelets (thrombocytopenia) can also be commonly seen. A blood film may show leukemic blast cells. Inclusions within the cells called Auer rods, when seen, make the diagnosis highly likely. A definitive diagnosis requires a bone marrow aspiration and biopsy.Bone marrow is examined under light microscopy, as well as flow cytometry, to diagnose the presence of leukemia, to differentiate AML from other types of leukemia (e.g. acute lymphoblastic leukemia), and to provide information about how mature or immature the affected cells are that can assist in classifying the subtype of disease. A sample of marrow or blood is typically also tested for chromosomal abnormalities by routine cytogenetics or fluorescent in situ hybridization. Genetic studies may also be performed to look for specific mutations in genes such as FLT3, nucleophosmin, and KIT, which may influence the outcome of the disease.Cytochemical stains on blood and bone marrow smears are helpful in the distinction of AML from ALL, and in subclassification of AML. The combination of a myeloperoxidase or Sudan black stain and a nonspecific esterase stain will provide the desired information in most cases. The myeloperoxidase or Sudan black reactions are most useful in establishing the identity of AML and distinguishing it from ALL.
Bennett; he used the term "leucocythemia" to describe this pathological condition.The term "leukemia" was coined by Rudolf Virchow, the renowned German pathologist, in 1856. As a pioneer in the use of the light microscope in pathology, Virchow was the first to describe the abnormal excess of white blood cells in people with the clinical syndrome described by Velpeau and Bennett. As Virchow was uncertain of the etiology of the white blood cell excess, he used the purely descriptive term "leukemia" (Greek: "white blood") to refer to the condition.Further advances in the understanding of AML occurred rapidly with the development of new technology. In 1877, Paul Ehrlich developed a technique of staining blood films which allowed him to describe in detail normal and abnormal white blood cells. Wilhelm Ebstein introduced the term "acute leukemia" in 1889 to differentiate rapidly progressive and fatal leukemias from the more indolent chronic leukemias. The term "myeloid" was coined by Franz Ernst Christian Neumann in 1869, as he was the first to recognize white blood cells were made in the bone marrow (Greek: μυєλός, myelos, lit. (bone) marrow) as opposed to the spleen. The technique of bone marrow examination to diagnose leukemia was first described in 1879 by Mosler. Finally, in 1900, the myeloblast, which is the malignant cell in AML, was characterized by Otto Naegeli, who divided the leukemias into myeloid and lymphocytic.In 2008, AML became the first cancer genome to be fully sequenced. DNA extracted from leukemic cells were compared to unaffected skin.