hematology and oncology
Secondary Erythrocytosis
Introduction
Secondary erythrocytosis is erythrocytosis that develops secondary to disorders that cause tissue hypoxia, inappropriately increased erythropoietin production, or increased sensitivity to erythropoietin. (See also Overview of Myeloproliferative Neoplasms .) In secondary erythrocytosis, only red blood cells (RBCs) are increased, whereas in Polycythemia Vera , RBCs, white blood cells (WBCs), and platelets will usually be increased. Any elevation of hemoglobin or hematocrit above normal values for age and sex is considered erythrocytosis. 