Polycythemia vera (PCV), polycythemia rubra vera (PRV), or erythremia, occurs when excess red blood cells are produced as a result of an abnormality of the bone marrow.

Polycythemia vera (PV, PCV) (also known as erythremia, primary polycythemia and polycythemia rubra vera) is a myeloproliferative blood disorder in which the bone marrow makes too many red blood cells.

Erythremia Osler-Vaquez Disease Primary Polycythemia Splenomegalic Polycythemia Vaquez-Osler Disease Polycythemia Rubra Vera None Polycythemia vera is a rare, chronic disorder involving the overproduction of blood cells in the bone marrow (myeloproliferation).