Polycythemia vera

In special circumstances, bone marrow tissue can undergo abnormal proliferation. Myeloid neoplasms characterized by clonal erythroid proliferation are generally referred to as polycythemia vera (PV). This is a chronic disease primarily characterized by an increased number of red blood cells in the peripheral blood and increased blood viscosity. Patients often present with elevated white blood cell and platelet counts, hepatosplenomegaly, and may experience complications such as bleeding or thrombosis. Some cases may progress to acute leukemia or myelofibrosis.