From the Guidelines
Management of patients with leukocytosis and primary thrombocytosis should focus on reducing thrombotic risk and addressing the underlying myeloproliferative disorder, with the cornerstone of treatment being cytoreductive therapy with hydroxyurea and low-dose aspirin. The goal of treatment is to prevent complications like stroke, myocardial infarction, or venous thromboembolism while managing symptoms and addressing the clonal hematopoietic disorder that drives both the leukocytosis and thrombocytosis. According to the most recent evidence, for patients presenting with hyperleukocytosis, defined as a WBC more than 100 10^9/L, immediate medical treatment is required, and hydroxyurea is recommended to lower WBC, given at dosages up to 50 to 60 mg/kg per day, until WBCs are less than 10-20 10^9/L 1. Key aspects of management include:
- Cytoreductive therapy with hydroxyurea, starting at 15-20 mg/kg/day, adjusted to maintain platelet count <400,000/μL
- Low-dose aspirin, 81-100 mg daily, to prevent thrombotic events
- Alternative agents, such as interferon-alpha, anagrelide, or ruxolitinib, for specific cases or patient populations
- Phlebotomy, if polycythemia is present
- Urgent plateletpheresis, reserved for acute thrombotic events or extreme thrombocytosis with symptoms
- Regular monitoring of blood counts, typically every 2-4 weeks initially, then every 3-6 months once stable Treatment decisions should be individualized based on thrombotic risk factors, age, and disease characteristics, with consideration of the patient's overall health and potential for complications 1.
From the Research
Leucocytosis and Primary Thrombocytosis Symptoms
- Leucocytosis, an increase in white blood cell count, and primary thrombocytosis, an increase in platelet count, can be associated with various symptoms, including thrombosis, bleeding, and microcirculatory symptoms such as headaches and acral paresthesias 2.
- Ischemic toe lesions with normal peripheral pulses can be a presenting symptom in primary thrombocytosis 3.
- Patients with thrombocytosis are at risk of developing thrombotic or hemorrhagic complications, and the risk of thrombosis is increased in patients with leucocytosis and JAK2V617F mutational status 4.
Management of Leucocytosis and Primary Thrombocytosis
- The management of patients with leucocytosis and primary thrombocytosis depends on the risk category, which is determined by factors such as age, previous thrombosis, and JAK2 mutational status 4, 5.
- Low-dose aspirin is recommended for all patients with essential thrombocythemia, and cytoreductive therapy is advised for high-risk and optional for intermediate-risk disease 2.
- Hydroxyurea and pegylated interferon-α are first-line cytoreductive drugs of choice, and busulfan is a second-line option 2.
- Patients with extreme thrombocytosis, pregnancy, splanchnic vein thrombosis, and perioperative care require specific treatment strategies 2.
- Platelet transfusion is recommended when patients have active hemorrhage or when platelet counts are less than 10 × 10^3 per μL, in addition to treatment of underlying causative conditions 6.