Diagnosis of myelodysplastic syndromes
The diagnosis of the myelodysplastic syndrome should include a complete blood count and peripheral blood smears. When a myelodysplastic syndrome is suspected, a bone marrow study should be performed including cytogenetic studies to detect genetic mutations. All of these studies are useful to diagnose and stage the disease.
- Complete blood count: Usually has either anemia, thrombocytopenia or neutropenia in the early stage of the disease. In a late stage of the disease, it may show 2 or 3 deficient cell counts (bicytopenia or pancytopenia, respectively).
- Peripheral blood smear: Red blood cells in anemia are oval-shaped and dimorphic, which means there are 2 cell populations or more. In cases of neutropenia, the nucleus is either nonsegmented or segmented into 6 to 7 lobes. In platelets, there are usually hypergranular platelets or big fragments of megakaryocytes in the blood.
- Bone marrow studies: It is more commonly hypercellular with dysplastic changes, but it can be hypocellular with aplastic anemia, too. Bone marrow fibrosis is present and may be confused with myeloproliferative diseases. Erythroid cell precursors usually have ringed sideroblasts and may display two or more nuclei. White blood cell precursors are usually larger than usual (hyperplasia), with increased blasts.
- Cytogenetic studies: Identification of chromosome abnormalities include a 7q deletion, 5q deletion, trisomy 8, or monosomy 7
Other studies that might be useful, depending on each patient, include:
- Serum vitamin B-12 and folate in red blood cells
- Serum erythropoietin, especially before deciding to transfuse blood
- Thyroid-stimulating hormone
- HIV testing