Characteristics, risk factors and management of venous thromboembolism in immune thrombocytopenia: a retrospective multicentre study

Abstract

Background: An increased risk of thrombosis has been reported in immune thrombocytopenic purpura (ITP), but the characteristics, risk factors of occurrence, recurrence and management of venous thromboembolic events (VTE) have been poorly investigated.Aims: To describe VTE and ITP characteristics, distribution of VTE risk factors and their impact on VTE features and recurrence.Methods: A retrospective study of patients with ITP and VTE registered in databases of three reference French centres of ITP.Results: Among 49 patients, 66 VTE were recorded. The platelet count at the time of the first VTE was <100 × 10 9 /L for 28/43 (65%) patients. In total, 19/48 (40%) patients had at least one positive antiphospholipid test result. For the 10 VTE occurring in eight patients with platelet count <50 × 10 9 /L, ITP treatment was efficient in 7. One haemorrhagic complication associated with anticoagulant (AC) therapy was recorded. For 31/49 (63%) patients, long-term AC therapy could have been discussed after the first VTE, but only 13 received it. A second VTE occurred in 13 (27%) patients. The risk of recurrence was increased in patients with unprovoked VTE before ITP diagnosis or active cancer.Conclusion: VTE in ITP mainly occurred in the presence of multiple risk factors of TE.A low platelet count does not protect against VTE. Management with AC therapy despite persistently low platelet count seems possible. Risk of VTE recurrence is high, particularly with a history of unprovoked VTE or active cancer. In this setting, indefinite AC therapy could be discussed.

Management of Vascular Thrombosis in Patients with Thrombocytopenia

“…18 While classical (e.g., advanced age, obesity, hormonal contraceptives, pregnancy/puerperium, cancer, recent surgery, history of VTE) and treatment-related risk factors (e.g., corticosteroids, high-dose intravenous immunoglobulins [IVIGs], splenectomy) contribute to the etiopathogenesis of VTE in ITP, thrombocytopenia does not protect against thrombosis. 19 Likewise, anticoagulation seems to be feasible in most patients with ITP and VTE despite persistently low platelet counts, which is consistent with a bleeding protective effect of increased IPFs. 19 Expert guidance on how to approach ITP patients with VTE or arterial thrombosis has recently been published.…”

Thrombosis in immune thrombocytopenia — current status and future perspectives

“…A retrospective analysis of 49 patients with ITP and VTE managed across three French ITP centres identified APL antibodies in 40% of the cohort, which was not in excess of that expected in ITP patients in general. 17 Altogether, 165 patients with ITP were monitored for the development of thrombotic events over a mean period of approximately five years. Of these, 42% had detectable APL antibodies (anti-cardiolipin or anti-b 2 glycoprotein) or were positive for a lupus anticoagulant according to the diluted Russell viper venom time (DRVVT).…”

“…Whether the presence of APL antibodies in ITP contributes to thrombogenesis has been questioned by several groups. A retrospective analysis of 49 patients with ITP and VTE managed across three French ITP centres identified APL antibodies in 40% of the cohort, which was not in excess of that expected in ITP patients in general 17 . Altogether, 165 patients with ITP were monitored for the development of thrombotic events over a mean period of approximately five years.…”

“…Higher rates of TE disease have been shown to be associated with advancing age, the presence of known arterial risk factors such as obesity, diabetes, hypertension and smoking, concomitant atrial fibrillation, and active malignancy. 10,14,16,17 Additionally, ITP therapies may have a role to play, and studies have also suggested that ITP itself may be a prothrombotic condition. 7,11 A summary of risk factors is provided in Fig 1.…”

Recurrent Arterial and Venous Thrombosis in Chronic Immune Thrombocytopenia: Clinical Paradox and Therapeutic Challenges

“…This has been addressed in a recent follow-up study of 49 ITP cases. Twenty seven percent patients with VTE and ITP had a recurrent VTE after a median delay of 110 months (range, 8-401 months), and median thrombosis-free survival was 8.8 months [10]. This study, and index case suggests that long-term (or indefinite) anti-coagulation is reasonable in ITP patients, especially those who have an unprovoked VTE, or recurrent VTE.…”