[Erythropoietin in the pathogenesis of anemia in patients with multiple myeloma]

Anemia is a common symptom in multiple myeloma (MM) patients but the pathogenesis of it is still unknown. The aim of the study was to explain the causes of anemia in MM patients. Peripheral blood count, bone marrow aspirate, iron and ferritin level, serum erythropoietin (EPO) level, T cell subsets and in vitro CFU-E count were analyzed in the group od 31 MM patients. Erythropoietin and iron deficiency in the study group were not observed. EPO serum level was not significantly different in patients with multiple myeloma and in comparison to patients with sideroblastic anemia with solid tumors. Absolute CD8 T lymphocyte count was not significantly increased in the study group. CFU-E colonies count in vitro was not decreased in these patients.

In the study group of the MM patients anemia probably does not depend on EPO production. Diminished proliferative response of erythropoietic cells on normal serum level of EPO and abnormal iron utilisation probably occur in these patients. Replacement of normal erythropoiesis by tumor plasma cells is probably not decisive.