From the Guidelines
Thrombocytosis is primarily caused by myeloproliferative neoplasms, such as essential thrombocythemia and polycythemia vera 1, as well as iron deficiency anemia and inflammation. Other potential causes include:
- Infection, trauma, or hemorrhage as a response to these conditions
- Certain medications, such as corticosteroids like prednisone, at doses of 10-20 mg daily for durations exceeding 1 week
- Thrombopoietic growth factors, like romiplostim, at doses of 1-10 μg/kg weekly
- Chronic diseases, including chronic kidney disease and rheumatoid arthritis Additionally, myeloproliferative neoplasms can lead to thrombocytosis due to increased platelet aggregation and thrombin generation 1. It is also worth noting that thrombocytosis can be a result of other factors, such as paroxysmal nocturnal hemoglobinuria, heparin-induced thrombocytopenia, and thrombotic thrombocytopenic purpura 1. However, these causes are less common and may not be directly related to the primary causes of thrombocytosis.
Some key points to consider when evaluating the causes of thrombocytosis include:
- The presence of JAK2V617F mutation, which can increase the risk of thrombosis in patients with myeloproliferative neoplasms 1
- The role of leukocytosis in increasing the risk of thrombosis in patients with essential thrombocythemia 1
- The potential for thrombopoietic growth factors to increase platelet count and contribute to thrombocytosis 1
- The importance of considering chronic diseases and inflammatory conditions as potential causes of thrombocytosis 1
From the FDA Drug Label
The FDA drug label does not answer the question.
From the Research
Causes of Thrombocytosis
Thrombocytosis can be classified into two main types: primary and secondary. The causes of thrombocytosis are varied and can be due to several factors.
- Primary thrombocytosis is often associated with myeloproliferative neoplasms (MPNs) and can be caused by mutations in genes that regulate thrombopoiesis, such as JAK2 2.
- Secondary thrombocytosis, on the other hand, can be caused by a range of factors, including:
Types of Thrombocytosis
There are different types of thrombocytosis, including:
- Essential thrombocythemia: a myeloproliferative neoplasm associated with mutations in genes that regulate thrombopoiesis 2
- Reactive thrombocytosis: a type of secondary thrombocytosis that is often encountered in the family medicine setting 2
- Extreme thrombocytosis: a rare condition characterized by a platelet count greater than 1000×10^9/L, often caused by multifactorial etiologies 4
Clinical Characteristics
The clinical characteristics of thrombocytosis can vary depending on the underlying cause.
- Patients with primary thrombocytosis tend to have a higher median platelet count and a higher incidence of thrombosis compared to those with secondary thrombocytosis 3.
- Patients with extreme thrombocytosis often have a multifactorial etiology, with surgical complications and hematologic malignancies being the most common causes 4.