What is the initial approach to managing patients with thrombocytosis (elevated platelet count)?

From the Guidelines

The initial approach to managing patients with thrombocytosis should involve determining whether the elevated platelet count is reactive or primary, and for primary thrombocytosis, particularly in essential thrombocythemia, low-dose aspirin is typically the first-line therapy to reduce thrombotic risk, with cytoreductive therapy using hydroxyurea considered in high-risk patients. When managing patients with thrombocytosis, it is crucial to distinguish between reactive (secondary) and primary causes, as this guides the treatment approach 1. For primary thrombocytosis, such as essential thrombocythemia (ET), the management strategy is based on the patient's risk category. Key considerations include:

• The use of low-dose aspirin in all patients with microvascular disturbances 1
• Cytoreduction with hydroxyurea as the first-line therapy in high-risk patients 1
• Aggressive management of cardiovascular risk factors and advice to stop smoking for all patients 1
• Consideration of platelet-lowering treatment when the platelet count exceeds 1,500 x 10^9/L due to the increased risk of bleeding 1 In high-risk patients, defined by factors such as a history of thrombosis, age greater than 60, or significantly elevated platelet counts, cytoreductive therapy is indicated to reduce the risk of thrombotic complications 1. Hydroxyurea is the preferred first-line cytoreductive agent due to its efficacy in lowering thrombotic complications compared to no treatment or other options like anagrelide 1. Regular monitoring of complete blood counts is essential to assess treatment response and detect potential complications early. Overall, the management of thrombocytosis requires a tailored approach based on the underlying cause and the patient's individual risk factors, with a focus on reducing thrombotic risk and improving quality of life 1.

From the Research

Initial Approach to Managing Patients with Thrombocytosis

The initial approach to managing patients with thrombocytosis (elevated platelet count) involves assessing the underlying cause of the condition and evaluating the risk of thrombotic complications.

• The discovery of driver-gene mutations in myeloproliferative neoplasms (MPNs) has simplified the diagnostic approach for thrombocytosis 2.
• Therapy for patients with essential thrombocythaemia aims to reduce their risk of thrombotic complications by addressing cardiovascular risk factors, and using antiplatelet agents and, in selected patients, cytoreductive therapy 3.

Treatment Recommendations

Treatment recommendations for patients with essential thrombocythaemia include:

• Low-dose aspirin (81-100 mg) once daily, which irreversibly inhibits platelet thromboxane A2 (TxA2) production by acetylating cyclo-oxygenase-1, is the recommended treatment for the control of vascular events in all ET risk categories, except patients at very low risk 4.
• Cytoreductive therapy may be considered in patients with high-risk essential thrombocythaemia, such as those with a history of thrombosis or haemorrhage 5.
• Hydroxyurea therapy may be used in high-risk patients, but its effectiveness in reducing platelet-leukocyte conjugates is limited 6.

Assessment and Diagnosis

Assessment and diagnosis of thrombocytosis involve:

• Evaluating the patient's medical history and performing physical examinations to identify potential underlying causes of thrombocytosis 3.
• Conducting laboratory tests, such as complete blood counts and blood smears, to confirm the diagnosis of thrombocytosis 2.
• Testing for driver-gene mutations, such as JAK2 V617F, to diagnose myeloproliferative neoplasms 5.