Related Diseases and Disease Complications
Secondary polycythemia (also called secondary erythrocytosis) is not a myeloproliferative neoplasm, but it does share a feature with polycythemia vera (PV): the overproduction of red cells. However, unlike PV, secondary polycythemia does not cause platelets or white cells to overproduce.
Secondary polycythemia is mainly caused by:
- ascent to a high altitude
- diseases that lead to low oxygen levels in the blood
- inherited disorders that result in overproduction or an exaggerated action of erythropoietin (the main hormone that stimulates red cell formation in the bone marrow)
- tumors that secrete erythropoietin, such as kidney tumors
In the case of high altitude or heart and lung diseases that lead to low blood oxygen content, secondary polycythemia is a physical response that the body makes to improve the blood's oxygen-carrying capacity.
Patients with PV may have high platelet counts, which can contribute to blood clot formation. Underlying vascular disease, commonly found in older persons with PV, can increase the risk of clotting complications. The clots may cause serious problems, such as stroke, heart attack, deep vein thrombosis or pulmonary embolism.
Blood clots occur in about 30 percent of patients before PV is diagnosed. Forty percent to 60 percent of PV patients may have blood clots during their first 10 years after diagnosis.
PV patients who haven't undergone treatment have an increased risk of bleeding complications from surgery. If you need surgery for any reason, your doctor should first treat you to bring your hematocrit and hemoglobin levels to normal.
People with PV are at slightly greater risk than the general population for developing leukemia as a result of the disease and/or certain drug treatments.