Elsevier

Thrombosis Research

Volume 130, Supplement 1, October 2012, Pages S74-S75
Thrombosis Research

Thrombosis in patients with primary chronic immune thrombocytopenia

https://doi.org/10.1016/j.thromres.2012.08.282Get rights and content

Abstract

Patients with primary chronic immune thrombocytopenia (ITP) have immune-mediated platelet destruction and/or suppressed platelet production. ITP patients are, due to the thrombocytopenia, at increased risk of severe bleeding episodes. Paradoxically, these patients also seem to have an increased risk of venous thromboembolism (VTE). Findings from a Danish study including 391 patients with chronic ITP and 3,128 comparisons from the general population have suggested a more than twofold higher risk of VTE in patients with chronic ITP compared with the general population. VTEs may occur even in patients with low platelet count. The conclusion is therefore that clinicians should keep VTE in mind as a potential diagnosis in patients with chronic ITP.

Section snippets

Immune thrombocytopenia

Primary immune thrombocytopenia (ITP) is an autoimmune hematological disorder characterized by low platelet count due to immune-mediated platelet destruction and/or suppressed platelet production [1], [2]. Persistence of thrombocytopenia for at least 12 months following ITP diagnosis is classified as chronic ITP [3]. In adults, ITP most often is a chronic disease with insidious onset [4]. The clinical presentations of ITP is symptomatic bleeding but may vary considerably from no bleeding

Platelet function in patients with chronic ITP

Two immune-mediated mechanisms play a role in the pathogenesis of chronic ITP: increased platelet destruction and decreased platelet production [2]. In a seminal study from 1951, Harrington provided the first evidence that thrombocytopenia in ITP is caused by a plasma-derived factor [8], later identified as an antiplatelet antibody [9]. These autoantibodies are often directed against epitopes of glycoprotein (GP) IIb/IIIa or GP Ib/IX although ITP patients may have antibodies directed against

Risk of Venous Thromboembolism (VTE)

Despite the presence of thrombocytopenia VTE has been reported to occur in patients with chronic ITP [15], [16]. Actually, ITP patients may paradoxically have an increased risk of VTE. This could be a consequence of more thrombotically active platelets or because of increased prevalence of known risk factors for VTE in patients with chronic ITP. Patients with chronic ITP may have a high prevalence of antiphospholipid antibodies or lupus anticoagulans [17], [18]. Chronic ITP patients also have

Conclusion

In conclusion, despite increased risk of bleedings patients with primary chronic ITP also have a higher risk of VTEs than the background population. VTEs can occur in patients with chronic ITP even in the presence of low platelet count and in the absence of antiphospholipid antibodies. Therefore, clinicians should keep this potential diagnosis in mind in patients with chronic ITP.

Conflicts of interest statement

The author did not report employment, consultancies, stock ownership, honoraria, paid expert testimony, grants, or consultancies that could inappropriately influence this manuscript. The Department of Clinical Epidemiology, Aarhus University Hospital Denmark is involved in studies with funding from various pharmaceutical companies as research grants to (and administered by) Aarhus University, Denmark.

References (23)

  • D.S. Beardsley

    ITP in the 21st century

    Hematology Am Soc Hematol Educ Program

    (2006)
  • Cited by (0)

    View full text