What is the Difference Between Primary Polycythemia and Secondary Polycythemia?
🆚 Go to Comparative Table 🆚Primary polycythemia and secondary polycythemia are both conditions that result in an increased red blood cell count, but they have different causes and characteristics.
Primary Polycythemia:
- Caused by an abnormality of the cells in the bone marrow that form red blood cells.
- Most commonly caused by an acquired genetic mutation in the Janus kinase 2 (JAK2) gene.
- Results in the overproduction and accumulation of red blood cells due to the mutation expressed within the hematopoietic stem cell or progenitor.
Secondary Polycythemia:
- Caused by a disorder originating outside of the bone marrow that causes overstimulation of the normal bone marrow, leading to an overproduction of red blood cells.
- Most commonly associated with low oxygen levels from tissue hypoxia, which can stimulate the kidneys to increase erythropoietin production.
- The overproduction of red blood cells is due to a number of factors, such as elevated levels of erythropoietin or other transcription factors.
In summary, primary polycythemia is caused by an intrinsic defect in the bone marrow cells, while secondary polycythemia is caused by external factors that lead to the overstimulation of the normal bone marrow. Both conditions result in an increased red blood cell count, but their origins and characteristics differ.
Comparative Table: Primary Polycythemia vs Secondary Polycythemia
Primary and secondary polycythemia are both disorders characterized by an overproduction of red blood cells. However, there are key differences between the two:
| Primary Polycythemia | Secondary Polycythemia |
|---|---|
| Also known as polycythemia vera | Caused by an underlying condition |
| Results from a mutation in hematopoietic stem cells | Caused by excess production of erythropoietin (EPO) or other factors |
| Elevated erythropoietin levels | Normal or suppressed erythropoietin levels |
| Increased levels of all three peripheral blood cell lines (RBCs, white blood cells, and platelets) | Increased levels of RBCs only |
| Neoplastic disorder | Rare condition |
| Involves increased proliferation of erythroid progenitor cells | Overproduction of RBCs due to an external factor |
| No intrinsic defect in erythroid progenitor cell lineage | Intrinsic defect in erythroid progenitor cell lineage |
Some common causes of secondary polycythemia include obstructive sleep apnea, smoking or lung diseases, obesity hypoventilation syndrome, chronic obstructive pulmonary disease (COPD), use of diuretics, and use of performance-enhancement drugs, including EPO, testosterone, and anabolic steroids.
- Polycythemia vs Polycythemia Vera
- Polycythemia vs Erythrocytosis
- Polycythemia Vera vs Essential Thrombocythemia
- Primary vs Secondary Hemostasis
- Primary vs Secondary Hypertension
- Hematopoiesis vs Erythropoiesis
- Primary vs Secondary Osteoporosis
- Pancytopenia vs Thrombocytopenia
- Myeloproliferative vs Myelodysplastic
- Primary vs Secondary Cells
- Sickle Cell Anemia vs Thalassemia
- Microcytic vs Macrocytic Anemia
- Primary vs Secondary Cell Culture
- Thalassemia Minor vs Thalassemia Major
- Red Blood Cells vs Platelets
- Primary vs Secondary Hypogonadism
- Hemolytic Anemia vs Iron Deficiency Anemia
- Thalassemia vs Anemia
- Hemochromatosis vs Thalassemia