88 Introduction to Myelodysplastic Syndromes (MDS)
Michelle To and Valentin Villatoro
Myelodysplastic syndromes are a group of clonal disorders that result in cytopenias and defective cell maturation.1 Morphology of cells during maturation show abnormalities, referred to as dysplasia.2 Dysplastic features seen varies in terms of the types of dysplasia seen, and the cell lines affected. Progression toward acute leukemia is often seen later in the disease, leading to an increase in blasts seen in the bone marrow and peripheral blood.
Age Group Affected: Commonly age of diagnosis is 70 years old.1
Affected Cell Line(s): Can affect one, two, or all three hematopoietic cell lines (erythroid, myeloid, megakaryocyte).1
Cause(s):
Chromosomal abnormalities
Mutations in oncogenes and tumor suppressor genes
General Laboratory Findings for MDS:2
PBS: Anemia Anisocytosis (Dimorphic) Poikilocytosis Sideroblasts Dysplastic granulocytes Dysplastic thrombocytes +/- Increased blasts |
BM: Dysplastic hematopoietic precursors Usually hypercellular (though hematopoiesis is ineffective) +/- Increased blasts |
Other Tests: Cytogenetic testing FISH Iron Studies: Serum Iron: Normal to Increased Serum Ferritin: Normal to Increased TIBC: Decreased to Normal |
References:
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.