Immune Thrombocytopenic Purpura and Paradoxical Thrombosis: A Systematic Review of Case Reports

Background and Aims: Immune thrombocytopenic purpura (ITP) is an acquired bleeding disorder characterized by autoantibodies against platelets. The clinical presentation is variable; the main symptom is bleeding, and many patients are asymptomatic; others have nonspecific symptoms like fatigue. Uncommonly, ITP can present with paradoxical thrombosis. The risk of thrombosis in ITP may be higher than expected, which makes the management of ITP more challenging. This review aims to evaluate patients with ITP who develop thrombosis and identify potential risk factors related to thrombosis in this category of patients. Materials and Methods: English literature was searched using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines for adults above 18 years with primary ITP who had infarctions or thrombotic events. Patients with secondary ITP were excluded. The search included articles published up to 20th October 2021. Results: A total of 73 articles were included. Seventy-seven patients with ITP had developed infarctions and various thrombotic events. Sixty-three patients had arterial events, and 14 patients developed venous thrombotic events. Conclusion: Patients with ITP have low platelets, which predispose them to bleed; despite that, serious thrombotic complications can happen in these patients and are difficult to predict. Therefore, it is critical for physicians to understand that ITP is paradoxically a prothrombotic condition and to address preventive thromboembolic measures whenever possible.