TABLE 1.
Some of the Diseases That Should Be Differentiated From MDS and Their Main Differentiating Features
| Idiopathic cytopenia of undetermined significance: no significant dysplasia or MDS-associated karyotypic aberrations |
| Acute myeloid leukemia: BM blasts ≥20%, presence of core-binding characteristic cytogenetic aberrations: t(8;21), t(15;17), inv(16) defines AML regardless of BM blast count; AML can be associated with hepatosplenomegaly or myeloid sarcomas |
| Chronic myeloid leukemia: presence of Philadelphia chromosome t(9;22) positive, basophilia, and splenomegaly |
| Myelofibrosis: significant BM fibrosis, splenomegaly, and leukoerythroblastic picture in PB (teardrop and nucleated RBCs, left-shifted myeloid cells) |
| Chronic myelomonocytic leukemia: significant PB monocytosis |
| MDS/MPN overlap syndromes: dysplasia with myeloproliferative characteristics such as splenomegaly, thrombocytosis, or leukocytosis |
| Infections: for example, HIV and parvovirus B19 infections |
| Myelophthisis: infiltration of BM with other tumors (eg, melanoma) with resultant PB cytopenias |
| Nutritional disturbances: B12, folate, and copper deficiency, and zinc and arsenic excess can mimic MDS |
| Medications: drugs that interfere with DNA synthesis such as HIV medications, chemotherapeutic agents, cotrimoxazole, methotrexate, azathioprine, and G-CSF |
| Immune disorders: for example, LGL leukemia, lupus, or rheumatoid arthritis |
| Other acquired or congenital hematological disorders: for example, paroxysmal nocturnal hemoglobinuria, congenital dyserythropoietic anemia, dyskeratosis congenita |