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A secondary erythrocytosis develops as a result of another disease or circulating erythropoiesis-stimulating substances.
In secondary erythrocytosis only the number of red blood cells is increased, while in the polycythemia vera (polycythemia vera) may increase the number of erythrocytes, leukocytes and platelets. Any increase in hemoglobin and hematocrit above normal for age and sex is considered erythrocytosis.
A secondary erythrocytosis develops as a result of another disease or circulating erythropoiesis-stimulating substances. In secondary erythrocytosis only the number of red blood cells is increased, while in the polycythemia vera (polycythemia vera) may increase the number of erythrocytes, leukocytes and platelets. Any increase in hemoglobin and hematocrit above normal for age and sex is considered erythrocytosis. Common causes of the development of secondary erythrocytosis are smoking chronic arterial hypoxemia tumors (tumor-associated erythrocytosis) Less common causes include certain congenital diseases such as hemoglobinopathies high O2 affinity erythropoietin receptor mutations Chuvash polycythemia (in which, by a mutation in the VHL gene is a hypoxia -sensitive signal is affected) proline-2 and hypoxia-induced factor 2 ? (HIF-2?) mutations can Spurious erythrocytosis (with hemoconcentration z. B. due to burns, diarrhea or diuretics) occur. In smokers, a reversible erythrocytosis occurs as a result of increased CO hemoglobin concentration in blood and the associated tissue hypoxia. Usually it comes to normalization of the values ??when the patient no longer smoke. Patients with chronic hypoxia (arterial Hb O 2 concentration <92%) typically as a result of lung disease, cardiac right-left shunts, prolonged stay at high altitude (altitude sickness) or hypoventilation syndrome often develop erythrocytosis. The aim of the initial regimen should be to improve the underlying disease. Nevertheless, O2 therapy or the prudent use of phlebotomy to reduce blood viscosity can improve the symptoms. Since in some cases the increased hematocrit is physiologically limited, Phlebotomy may hurt by the decreasing tissue oxygenation. The tumor-associated polycythemia may occur if renal tumors and cysts, liver tumors, cerebellar hemangioblastoma or uterine leiomyomas lead to a release of erythropoietin. Surgical removal of the corresponding change may be curative. Hemoglobinopathies high O2 affinity are very rare. This diagnosis can be suspected if a polycythemia is already known in a family. The diagnosis is made by measuring the P50 (O2 partial pressure at which hemoglobin is 50% saturated), and, if possible, by the provision of a complete oxygen dissociation curve of hemoglobin. Since the standard hemoglobin electrophoresis may be normal, it can not exclude certain this cause of erythrocytosis. Review The tests with existing erythrocytosis include arterial O2 saturation of serum erythropoietin P50 A low or low-normal serum erythropoietin levels in favor of a polycythemia vera. Patients with hypoxia-induced erythrocytosis have an increased erythropoietin or related to the increased hematocrit unusually normal. Increased erythropoietin typically have patients with tumor-associated erythrocytosis. In patients with increased erythropoietin or microscopic hematuria imaging of the abdomen and / or the central nervous system should be performed to place after kidney damage or other erythropoietin-producing tumors. P50 determines the affinity of hemoglobin for O2; an unobtrusive finding includes hemoglobin variants with high oxygen affinity (a familial disorder) as a cause of erythrocytosis from.