ABSTRACT
The myelodysplastic syndromes (MDS) are a heterogeneous group of hematologic disorders that are clinically characterized by peripheral cytopenias due to ineffective hematopoiesis and progressively impaired ability of progenitor cells to differentiate (1). The erythroid lineage is the most commonly affected and, as a result, anemia is the most frequent peripheral cytopenia observed. According to the World Health Organization (WHO) definition of anemia (hemoglobin 13 g/dL for men and12 g/dL for women) more than 90% of MDS patients are anemic at the time of diagnosis, while moderate to severe anemia (hemoglobin10 g/dL) is observed in almost 60% of cases (2). Severe anemia is usually symptomatic, and the majority of these patients eventually need to be treated with regular red blood cell transfusions, the frequency of which usually increases over time.
