Which polycythemia is associated with chronic hypoxia?

Which polycythemia is associated with chronic hypoxia?

• A. Primary polycythemia
• B. Polycythemia Vera
• C. Relative polycythemia
• D. Secondary polycythemia

Answer: (D)

Chronic hypoxia drives secondary polycythemia because low oxygen levels stimulate the kidneys to increase erythropoietin production. That EPO surge tells the bone marrow to make more red blood cells, raising the red cell mass as a compensatory response to improve oxygen delivery. This differs from primary polycythemia vera, which is due to a clonal overproduction of red cells that occurs independently of EPO (often with low EPO levels), and from relative polycythemia, where the apparent high hematocrit is due to reduced plasma volume rather than true excess red cells. So the link to chronic hypoxia specifically points to secondary polycythemia.

Chronic hypoxia drives secondary polycythemia because low oxygen levels stimulate the kidneys to increase erythropoietin production. That EPO surge tells the bone marrow to make more red blood cells, raising the red cell mass as a compensatory response to improve oxygen delivery. This differs from primary polycythemia vera, which is due to a clonal overproduction of red cells that occurs independently of EPO (often with low EPO levels), and from relative polycythemia, where the apparent high hematocrit is due to reduced plasma volume rather than true excess red cells. So the link to chronic hypoxia specifically points to secondary polycythemia.