Severe case of refractory immune thrombocytopenic purpura requiring splenectomy after the COVID-19 vaccine

Antibodies against Platelet Glycoproteins in Clinically Suspected VITT Patients

Vaccine-induced thrombotic thrombocytopenia (VITT) is a rare but severe complication following COVID-19 vaccination, marked by thrombocytopenia and thrombosis. Analogous to heparin-induced thrombocytopenia (HIT), VITT shares similarities in anti-platelet factor 4 (PF4) IgG-mediated platelet activation via the FcγRIIa. To investigate the involvement of platelet-antibodies in VITT, we analyzed the presence of platelet-antibodies directed against glycoproteins (GP)IIb/IIIa, GPV and GPIb/IX in the serum of 232 clinically suspected VITT patients determined based on (suspicion of) occurrence of thrombocytopenia and/or thrombosis in relation to COVID-19 vaccination. We found that 19% of clinically suspected VITT patients tested positive for anti-platelet GPs: 39%, 32% and 86% patients tested positive for GPIIb/IIIa, GPV and GPIb/IX, respectively. No HIT-like VITT patients (with thrombocytopenia and thrombosis) tested positive for platelet-antibodies. Therefore, it seems unlikely that platelet-antibodies play a role in HIT-like anti-PF4-mediated VITT. Platelet-antibodies were predominantly associated with the occurrence of thrombocytopenia. We found no association between the type of vaccination (adenoviral vector vaccine versus mRNA vaccine) or different vaccines (ChAdOx1 nCoV-19, Ad26.COV2.S, mRNA-1273, BTN162b2) and the development of platelet-antibodies. It is essential to conduct more research on the pathophysiology of VITT, to improve diagnostic approaches and identify preventive and therapeutic strategies.

Immune Thrombocytopenia After COVID-19 Vaccine Requiring Splenectomy: A Case Report and Review of the Literature

Post-vaccination immune thrombocytopenia (ITP) is a rare but recognized adverse event believed to result from an autoimmune reaction triggered by the vaccine. This case report presents the fourth documented instance of severe ITP requiring splenectomy following the administration of a COVID-19 vaccine. The patient, a 54-year-old previously healthy female with no familial history of autoimmune or hematological disorders, developed ITP two weeks after the first dose of the COVID-19 vaccine. While most ITP cases associated with COVID-19 vaccines manifested after the second dose, this unique case demonstrated symptoms following the initial vaccination. Initially responsive to first-line management, the patient experienced a relapse upon receiving the second dose from a different vaccine manufacturer. Despite exhaustive medical interventions, the refractory nature of the condition persisted, ultimately mandating splenectomy for the achievement of complete remission. This case underscores the potential for serious, refractory ITP with the second dose of a COVID-19 vaccine, particularly in patients who initially developed ITP after the first dose, even if they had seemingly achieved complete remission. These findings emphasize the importance of vigilant monitoring and individualized treatment strategies in such cases, contributing valuable insights to the growing body of knowledge surrounding vaccine-induced ITP.