Bleeding complications are a major concern for patients with
The report,
Though paradoxical, bleeding complications are relatively common in ET, the authors explained.
“Bleeding in ET can range from minor mucocutaneous bleeding (such as frequent nosebleeds, easy bruising or gum bleeding) to minor hemorrhages like gastrointestinal bleeds and intracranial hemorrhage,” they wrote.
The actual incidence of major bleeding events in people with ET is not well-documented, the authors said, though
However, the concern is most notable among patients with the JAK2 V617F variant, who are at an increased risk of bleeding and thrombosis, the authors noted. Managing such patients can be difficult, they said, due to inadequate risk-stratification tools and a lack of testing for complications.1
There are a number of potential causes of major bleeding in ET, but the investigators said one of the most well-known is acquired von Willebrand syndrome (AvWS) caused by extreme platelet elevation.
“In ET, when platelet counts are markedly elevated, the platelets can adsorb large VWF (von Willebrand factor) multimers out of circulation and promote their degradation,” they said.
Intrinsic platelet function abnormalities can also lead to bleeding in patients with ET, the authors added. They noted that some patients have prolonged bleeding times, even with antiplatelet agents. Platelet ultrastructure and biochemistry can also be altered in ET, they said.
Historically, the authors noted, thrombocytosis > 1000 × 109/L was considered an indicator of biochemical type 2 AvWS. However, the investigators said a significant proportion of patients who do not meet that parameter also experience reductions in VWF activity. They said clinicians should be cautious about relying solely on platelet count to gauge bleeding risk.
The authors also explained the use of antiplatelet and anticoagulation therapy could increase bleeding risk. Other factors associated with bleeding risk include being over the age of 60 years, a prior history of bleeding, splenomegaly, leukocytosis, and diabetes mellitus, they added.
There is debate about whether or not all patients with ET ought to be tested for AvWS. The authors said a “middle ground” might be to screen patients who have a higher pre-test probability of bleeding risk or patients whose management would be immediately impacted by the results.
When acute bleeding occurs in patients with ET-associated AvWS, the investigators said treatment should focus on rapid restoration of hemostatic function. The first-line treatment for severe hemorrhages, they said, is plasma-derived VWF/factor VIII concentrates.
The authors said there are several conundrums regarding the management of patients with AvWS in ET. Among them are whether aspirin should be given to such patients, and whether cytoreduction should be used. In both cases, the investigators said there is a lack of definitive evidence. They added that careful planning of periprocedural hemostasis is also a crucial task in patient management.
“Ultimately, clinicians must balance between preventing thrombosis and bleeding by tailoring management to each patient,” they concluded.
References
- Gurumurthy G, Gurumurthy S, Somervaille TCP, Falanga A, Thachil J. Bleeding complications in JAK2-variant essential thrombocythemia: a revisit in 2025. EJHaem. 2025;6(4):e70088. doi:10.1002/jha2.70088
- Finazzi G, Carobbio A, Thiele J, et al. Incidence and risk factors for bleeding in 1104 patients with essential thrombocythemia or prefibrotic myelofibrosis diagnosed according to the 2008 WHO criteria. Leukemia. 2012;26(4):716-719. doi:10.1038/leu.2011.258
- Stuckey R, Ianotto JC, Santoro M, et al. Prediction of major bleeding events in 1381 patients with essential thrombocythemia. Int J Hematol. 2023;118(5):589-595. doi:10.1007/s12185-023-03650-7