Polycythemia is best described as which of the following?

Polycythemia is best described as which of the following?

• A. Too many white blood cells
• B. Too many red blood cells
• C. Low platelets
• D. Decreased hemoglobin

Answer: (B)

An excess of red blood cells defines polycythemia. When there are more red blood cells than normal, the total red cell mass and hematocrit rise, making the blood thicker and increasing the risk of clotting. This description specifically points to too many red blood cells, not to changes in white blood cells, platelets, or a decrease in hemoglobin. Leukocytosis would mean too many white cells, thrombocytopenia means too few platelets, and decreased hemoglobin indicates anemia rather than polycythemia.

An excess of red blood cells defines polycythemia. When there are more red blood cells than normal, the total red cell mass and hematocrit rise, making the blood thicker and increasing the risk of clotting. This description specifically points to too many red blood cells, not to changes in white blood cells, platelets, or a decrease in hemoglobin. Leukocytosis would mean too many white cells, thrombocytopenia means too few platelets, and decreased hemoglobin indicates anemia rather than polycythemia.