Profound thrombocytopenia related with tirofiban: will it be enough to only stop medicine?

Tirofiban-induced thrombocytopenia

Tirofiban is a small non-peptide ligand-mimetic Glycoprotein (GP) IIb/IIIa inhibitor which can reversibly bind to the arginine-glycine-aspartic acid (RGD) recognition site of GP IIb/IIIa to prevent platelet aggregation. It reduces the incidence of thrombotic cardiovascular events in patients with non-ST-segment elevation acute coronary syndrome (NSTE-ACS). Although generally considered safe, tirofiban has been reported to be associated with thrombocytopenia in several case reports and clinical trials. The pathogenesis for this adverse reaction is not entirely understood, is thought to be due to immune-mediated reaction. This side effect caused by tirofiban is especially concerning given how frequently it is used in the practice of contemporary cardiovascular care. The present review provides an overview of the pathophysiology, clinical presentation, management, and risk factors associated with tirofiban-induced thrombocytopenia.

Severe Acute Thrombocytopenia After Treatment with Tirofiban: A Case Series Approach

Glycoprotein IIb/IIIa inhibitors are an adjuvant therapy for the treatment of patients with acute coronary syndromes. The main adverse reactions are bleeding and thrombocytopenia in 1-2% of cases. A 66-year-old woman arrived at the emergency department with ST-elevation MI. The catheterisation lab was busy, so she received thrombolytic therapy. Coronary angiography revealed a 90% stenosis in the middle segment of the left anterior descending artery and Thrombolysis in MI 2 flow. Subsequent percutaneous coronary intervention showed abundant thrombus and a coronary dissection and it was necessary to insert five drug-eluting stents. Non-fractionated heparin and a tirofiban infusion were used. After the percutaneous coronary intervention, she developed severe thrombocytopenia, haematuria and gingivorrhagia, for which infusion of tirofiban was suspended. In follow-up, no major bleeding or subsequent haemorrhagic complications were identified. It is crucial to distinguish between heparin-induced thrombocytopenia and thrombocytopenia caused by other drugs. A high level of suspicion should be employed in these cases.

Tirofiban Induced Thrombocytopenia: A Rare but Severe Adverse Effect

With the advent of medical technology, coronary angiography is a common practice to evaluate patient for coronary artery disease. Normally, patients undergoing angiogram receive antiplatelets, anticoagulants, and platelet aggregation inhibitor agents. Glycoprotein IIb/IIIa receptor inhibitors are a type of platelets antiaggregant agents that can cause severe thrombocytopenia in very few cases. We present a case of a 69-year-old female who presented with chest pain, underwent an angiography and had two stents placed. She was administered tirofiban during angiogram that caused acute severe thrombocytopenia decreasing her platelets count from 224 to 2 k/mm³ within 1 day. Patients platelets gradually recovered after trial of steroid and platelets transfusion. Antiplatelets (Aspirin and Clopidogrel) were resumed; however, patient’s platelets remained stable.

[Long-lasting thrombocytopenia induced by glycoprotein IIb/IIIa inhibitor]

INTRODUCTION

Glycoprotein IIb/IIIa inhibitors (anti-GPIIbIIIa) prevent platelet binding to fibrinogen. Transient sometimes-severe thrombocytopenia is a well-known side effect.

OBSERVATION

A 71-year-old patient presented severe thrombocytopenia after the administration of tirofiban (anti-GPIIbIIIa). Corticosteroid treatment was initiated at day 10 because of persistence of severe thrombocytopenia with poor platelet transfusion efficacy. Corticosteroid treatment led to platelet recovery evoking an immune mediated mechanism for thrombocytopenia.

CONCLUSION

Anti-GPIIbIIIa are associated with a risk of dramatic thrombocytopenia. The underlying mechanism is poorly understood. The management of these usually transient thrombocytopenias is based on platelet transfusion. As report here, in some cases persistent thrombocytopenia can respond to corticosteroids.