Minimal criteria for the diagnosis of the myelodyplastic syndrome:
(1) both of the following ("prerequisite" criteria)
(1a) constant cytopenia in at least one cell lineage (erythroid, myeloid, megakaryocytic)
(1b) exclusion of other causes of cytopenia and/or dysplasia
(2) at least one of the following ("decisive" criteria)
(2a) documentation of typical chromosomal abnormalities (+8, -7, 5q-, 20q-, etc)
(2b) 5-19% blasts in the bone marrow
(2c) > 15% ringed sideroblasts
(2d) >= 10% dysplasia in all cells of at least one lineage (erythroid, myeloid, megakaryocytic)
where:
• Cytopenia was defined as hemoglobin < 11 g/dL, absolute neutrophil count < 1,500 per µL, platelet count < 100,000 per µL.
• If the only decisive criteria present is the chromosomal abnormality, then the diagnosis should be "highly suspicious for MDS."
• Some patents may have MDS despite the presence of another disease causing cytopenia or dysplasia.
If none of the decisive criteria are present, then the presence of "co-criteria" can be used to support the diagnosis in a patient showing clinical features of MDS such as macrocytic transfusion-dependent anemia:
(1) monoclonal population of erythroid and/or myeloid cells on flow cytometry
(2) monoclonal cell population by molecular method (HUMARA assay, gene chip profiling, point mutation analysis, etc)
(3) persistent and marked reduction in colony forming units (CFU) in bone marrow and/or circulating stem cells
