CYTOMETRIC ANALYSIS AND MATURATION CHARACTERISTICS OF RETICULOCYTES FROM MYELODYSPLASTIC PATIENTS

Myelodysplasia is characterized by a hypoproliferative anaemia with in effective intramedullary erythropoiesis. We have used the novel techno logy of the Bayer H3 analyser to characterize reticulocytes (RNA conta ining red cells) from 32 MDS patients and 10 elderly normal subjects. In comparison with reticulocytes from normal subjects, those from MDS patients were larger with a lower haemoglobin concentration. Reticuloc ytes from sideroblastic patients had a lower haemoglobin content and c oncentration than for refractory anaemia patients but no other differe nces between FAB subtypes were found. H3 reticulocyte RNA content para meters correlated poorly with those derived by the Sysmex R-1000, part icularly in the MDS group. On reticulocyte maturation to red cells MDS patients concentrated haemoglobin more than normal subjects and this was most evident in the sideroblastic group, Platelet depletion of who le blood suggested that large platelets in the sideroblastic group may have partly contributed to this observation. Prospective evaluation o f changes towards normal reticulocyte cytometric parameters may assist in assessment of early erythroid response to therapy in MDS patients.