A 50-year-old nonsmoking male presents with massive splenomegaly, very high hematocrit, and hyperviscosity. Which intervention would be most helpful?

• A. Erythropoietin
• B. Oral anticoagulants
• C. Alpha-interferon
• D. Periodic phlebotomy

Answer: (D)

Massive splenomegaly with a very high hematocrit and hyperviscosity points to polycythemia vera, a myeloproliferative disorder with excess red cell mass. The most helpful intervention is periodic phlebotomy to rapidly lower the hematocrit, which directly reduces blood viscosity and the risk of thrombosis while alleviating related symptoms. After hematocrit is controlled, other measures such as low-dose aspirin for thrombosis prevention and cytoreductive therapy (e.g., hydroxyurea or interferon) for persistent high-risk disease can be considered. Erythropoietin would worsen the problem by increasing red cell production, while anticoagulants don't address the underlying elevated red cell mass, and alpha-interferon, though useful for cytoreduction, works more slowly and is not the immediate first-line intervention for hyperviscosity.