American Board of Internal Medicine (ABIM) Certification Practice Exam

What is the best treatment option for essential thrombocythemia in patients older than 60 years with a platelet count greater than 1 million/µL?

1. Glucocorticoids

2. Hydroxyurea plus low-dose aspirin

3. Rituximab

4. Splenectomy

The correct answer is: Hydroxyurea plus low-dose aspirin

In the management of essential thrombocythemia, particularly in older patients (those over 60 years) who have a significantly elevated platelet count (greater than 1 million/µL), the primary goals are to reduce platelet levels and minimize the risk of thrombotic complications. The use of hydroxyurea plus low-dose aspirin is considered the best treatment option in this scenario. Hydroxyurea is a cytoreductive agent that helps to lower platelet counts and decrease the risk of vascular events by reducing the overall number of circulating platelets. Low-dose aspirin is added for its antiplatelet properties, which further contributes to reducing vascular risk by inhibiting platelet aggregation. This combination therapy is particularly favorable due to its effectiveness in managing symptoms and preventing thrombotic complications, which are heightened in older patients with high platelet counts. Hydroxyurea has a well-established safety profile and is often the first-line cytoreductive therapy for high-risk patients with essential thrombocythemia. In contrast, while glucocorticoids might be used in certain contexts for their anti-inflammatory effects, they are not effective in specifically lowering platelet counts in essential thrombocythemia. Rituximab is more commonly associated with conditions like