Which of the following anemias is associated with an increased risk of thrombosis due to an imbalance in blood viscosity?

A Sickle cell anemia
B Thalassemia major
C Polycythemia vera ✓
D Hereditary spherocytosis

Explanation

Polycythemia vera is associated with an increased risk of thrombosis due to the excessive production of red blood cells, which leads to increased blood viscosity.

Source

Harrison's Principles of Internal Medicine
Hematology Hematology: Anemia Hematology: Anemia Hard MEDICAL Confidence: high