[Heterogeneity of ineffective erythropoiesis in myelodysplastic syndromes evaluated by application of newly devised...

Ineffective erythropoiesis was evaluated in 100 studies in 87 patients with myelodysplastic syndromes (MDS) applying newly devised parameters based on ferroerythrokinetic (FEK) data including erythron transferrin uptake (ETU). The efficiency ratio (R-Ef) was calibrated with V-2, the second canonical discriminant variate which underwent axis rotation. Based on discriminated FEK patterns, as previously reported, the patients were classified into five types i.e. I-z, ineffective, H-z, hemolytic hyperplastic, O-z, hypoplastic, I-H-z and I-O-z, combination of these, groups. The proportion of I-z group was 48% and that of I-H-z and I-O-z groups was 30%. Significant correlations were obtained in I-z group between R-Ef and ETU (r = -0.628), unclear abnormality scores (R = 0.664) or ringed sideroblast scores (R = 0.742), scored by dummy variables regression. In the other groups, significant deviation from these correlations was observed, indicating that there is an obvious heterogeneity in MDS patients concerning association or dissociation of morphological abnormality, in addition to hyperplasia of erythroblasts, with or from ineffective erythropoiesis.