This case of rapidly regenerating agranulocytosis was diagnosed as MDS by 30% of the the participants of the \\\"Instand\\\" quality control round | Bone marrow is dominated by neutrophilic precursors | Mature granulocytes are lacking. Few band forms are present. |
 |  |  |
|
Many participants made a diagnosis of MDS. However, there is no dysplastic sign. Granulation of the more mature cells is clearly visible. | Left shift does not prove the neoplastic nature. The quantitative relation between many promyelocytes and very few blasts is compatible with regeneration. | One further blast |
 |  |  |
|
Of course, blasts are suggestive of neoplasia. However, in states of rapid regeneration like agranulocytosis and in case of regeneration after chemotherapy for e.g. AML, some blasts can be found. | Many cases of agranulocytosis show involvement of the erythropoietic lineage demonstrated by the "dysplastic" irregularly shaped nuclei | It is dangerous to use "dysplastic" features of erythroblasts like this irregularly shaped nucleus to establish an MDS diagnosis. |
 |  |  |
|