blood disorders
Polycythemia Vera
Diagnosis of Polycythemia Vera
Blood tests Genetic tests and other tests Polycythemia vera may be discovered through a blood count done for another reason, even before people have any symptoms. The number of red blood cells, the level of the protein that carries oxygen in red blood cells (hemoglobin) and the percentage of red blood cells in the total blood volume (the hematocrit) are abnormally high. The number of platelets and white blood cells may also be increased. Doctors consider polycythemia vera a possibility if the hematocrit is very high. However, the diagnosis cannot be based solely on the hematocrit result. Once the increase in the red blood cell count (polycythemia) is discovered, doctors must determine whether the person has polycythemia vera or polycythemia caused by some other condition ( Secondary Erythrocytosis ). The medical history and examination may help differentiate between polycythemia vera and secondary erythrocytosis, but doctors must usually investigate further. Blood levels oferythropoietin, a hormone that stimulates the bone marrow to produce red blood cells, also may be measured. Levels oferythropoietinare usually, extremely low in polycythemia vera, and they are often, but not always, normal or high in secondary erythrocytosis. People are tested forJAK 2gene mutations to confirm the diagnosis of polycythemia vera. If those mutations are not found, doctors look forCALRand sometimes other mutations, which are also helpful in confirming the diagnosis. 