89 MDS: Dyserythropoiesis, Dysmyelopoiesis & Dysmegakaryopoiesis
Michelle To and Valentin Villatoro
As previously discussed, MDS is a clonal disorder that results in defective cell maturation and results in dysplastic changes. The dysplasia can be seen in both the peripheral blood and in the bone marrow. Dysplasia may be seen in one or more cell lines, and the types of dysplasia seen vary. Below are descriptions that may be seen, organized by cell lineage.
Affected Cell line: Erythroids.1-3
Table 1. Dysplastic features found in MDS erythrocytes in the peripheral blood and bone marrow.1-3
Hypochromic/Microcytic RBCs (with normal iron stores)
Abnormal Nuclear shapes (budding, lobes, fragmentation, bridging)
Abnormal staining of the cytoplasm (due to basophilic stippling and hemoglobin)
Affected Cell line: Granulocytes.1-3
Table 2. Dysplastic features found in MDS granulocytes in the peripheral blood and bone marrow. 1-3
Abnormal nuclear shapes (hypersegmentaion, hyposegmentation, ring-shaped nuclei)
Abnormal cytoplasmic staining
Abnormal granulation (hypogranulation, hypergranulation)
+/- Auer rods
Affected Cell line: Megakaryoctyes and platelets.1-3
Table 3. Dysplastic features found in MDS megakaryocytes and platelets in the peripheral blood and bone marrow. 1-3
Magakaryocytes with multiple separated nuclei
Abnormal granulation (hypogranulation)
Large mononuclear megakaryocytes
Platelet function tests are abnormal
1. Rodak BF. Myelodysplastic syndromes. In: Rodak’s hematology clinical applications and principles. 5th ed. St. Louis, Missouri: Saunders; 2015. p.591-603.
2. Lawrence LW, Taylor SA. Myelodysplastic syndromes. In: Clinical laboratory hematology. 3rd ed. New Jersey: Pearson; 2015. p. 479-99.
3. D’Angelo G, Mollica L, Hebert J, Busque L. Myelodysplastic syndromes. In: Clinical hematology and fundamentals of hemostasis. 5th ed. Philadelphia: F.A. Davis Company; 2009. p. 412-39.