Characteristics of patients with secondary erythrocytosis in relation to patients with polycythemia vera

Abstract

Introduction: Erythrocytosis represents elevated hemoglobin and hematocrit levels above the range of normal values. Primary erythrocytosis - polycythemia vera, is characterized by increased erythrocyte production, due to a disorder at the level of the multipotent stem cell in the bone marrow. On the other hand, secondary erythrocytosis (SE) is the result of bone marrow stimulation by an external factor. Aim: The aim of our study was to determine parameters which are significant in differentiating SE from primary erythrocytosis - polycythemia vera (PV). Materials and methods: This is a retrospective study involving 108 patients with SE and 111 patients with PV, who were diagnosed and treated at the Clinic of Hematology of the Clinical Center of Serbia (CCS), in the period: December 2005 - November 2018.From the patient records, the following data were extracted: demographic characteristics, laboratory parameters, spleen size, total red cell mass, serum erythropoietin (EPO) level, and spontaneous growth of the BFU-E colony. Results: Patients with SE were younger, with a predominance of the male gender and with significantly higher serum EPO values than patients with PV. Patients with PV had significantly higher values of BFU-E, leukocyte and platelet count, spleen size, and LDH level than patients with SE. Total red cell mass analysis did not show a differential diagnostic significance. Conclusion: Findings of normal spleen size, normal leukocyte and platelet count, normal serum LDH level, and elevated EPO, in patients, refer to the diagnosis of secondary erythrocytosis, while the findings of splenomegaly, leukocytosis, thrombocytosis, elevated serum LDH level, decreased EPO, and the presence of spontaneous BFU-E colony speak in favor of the diagnosis of polycythemia vera.