Acute profound thrombocytopenia associated with anaphylactic reaction after abciximab therapy during percutaneous coronary angioplasty

Biologics and anaphylaxis

PURPOSE OF REVIEW

The use of biologicals as therapeutic agents in oncology and other inflammatory diseases has dramatically increased during the last years. Due to their biological nature and inherent immunological activity, they are able to induce important adverse events, such as cytokine release reactions (rapid release of proinflammatory cytokines), serum sickness disease, and immediate or delayed hypersensitivity reactions, including anaphylaxis. The aim of the current article is to review the state of the art of anaphylaxis because of biological agents.

RECENT FINDINGS

Different phenotypes, and potential underlying endotypes, have been described in anaphylactic reactions to biologicals. There seems to be a spectrum from type 1 reactions (IgE or non-IgE-mediated) to cytokine release reactions, with some reactions falling in between both. Management should be directed according to such phenotypes.

SUMMARY

There is ongoing research to further define immediate adverse reactions to biologicals and to find relevant biomarkers to aid in their diagnosis. Such information will serve in defining their immediate and long term management.

Hypersensitivity reactions to biologics (part I): allergy as an important differential diagnosis in complex immune-derived adverse events

Purpose

Biotechnological substances (BSs) are strongly relied upon to prevent rejection of transplanted organs, and to treat oncological, allergological, and other inflammatory diseases. Allergic reactions to partly foreign biologics can occur due to their potential immunogenicity. The severity of an immune response to a biological drug may range from no clinical significance to a severe, life-threatening anaphylactic reaction.

Methods

Detailed searches were performed on Pubmed, Web of Science, and Google Scholar to include all available publications. In addition, the Food and Drug Administration, the European Medicines Agency, and British Columbia Cancer Agency Drug Manual databases were screened for hypersensitivity reaction (HSR), infusion reaction, injection site reaction, urticaria, and anaphylaxis for individual BSs.

Results

Treatment with BSs can cause various types of HSR. These are mentioned in the literature with definitions such as allergic reactions, anaphylactoid reactions, anaphylaxis, HSR, infusion reactions, injection site reactions, cytokine release syndrome, and urticaria. Due to the overlap in signs and symptoms in the reported descriptions, it is not always possible to differentiate these reactions properly according to their pathomechanism. Similarly, many data reported as anaphylaxis actually describe severe anaphylactic reactions (grades III or IV).

Conclusion

There is an urgent need for a simpler symptom- or system-based classification and scoring system to create an awareness for HSRs to BSs. A better understanding of the pathophysiology of HSRs and increased clinical experience in the treatment of side effects will provide timely control of unexpected reactions. As a result, immunotherapy with BSs will become safer in the future.

Hypersensitivity reactions to modern antiplatelet and anticoagulant drugs

Anticoagulation and antiplatelet drugs are among the most commonly used medical drugs. In addition to the long-established heparins, hirudins, coumarins and antiplatelet drugs such as acetylsalicylic acid, numerous novel and predominantly synthetic pharmacologic agents have come onto the market in recent years. These new agents act at various sites in coagulation and have significantly broadened treatment options. Whilst immunological hypersensitivity reactions are on the whole rare, they have a considerable impact on patient management when they do occur. The present overview discusses the currently known hypersensitivity reactions to anticoagulant and antiplatelet agents, with particular attention to the newer substance classes including P2Y₁₂ inhibitors, glycoprotein IIb/IIIb receptor antagonists, direct factor Xa inhibitors and direct thrombin inhibitors.

Acute profound abciximab induced thrombocytopenia: a correct management of a methodological error

Thrombocytopenia is a rare complication of glycoprotein IIb/IIIa treatment. We report a case of an acute profound abciximab induced thrombocytopenia and its successful management. The patient, presenting with unstable angina, underwent percutaneous coronary intervention with implantation of three drug eluting stents without receiving a clopidogrel loading dose according to guidelines. The rapid drop in the platelet count after abciximab elastomeric pump infusion was treated with drug discontinuation and platelet transfusion. The high risk of stent thrombosis was avoided by a timely readministration of the dual antiplatelet treatment.

Thrombocytopenia associated with antithrombotic therapy in patients with cardiovascular diseases: diagnosis and treatment

Agents with antiplatelet and anticoagulant activity have been proved to be effective in reducing the incidence of complications following acute coronary syndrome, percutaneous coronary intervention, and cardiopulmonary bypass. However, these agents, including heparin, glycoprotein IIb/IIIa receptor inhibitors, and thienopyridines, are associated with increased risk of bleeding and thrombocytopenia and have been administered together with increasing frequency in a variety of cardiovascular settings. Therefore, clinicians must be familiar with the safety and rational use of these potent antithrombotic agents. Clinical features of thrombocytopenia range from bleeding to thrombosis, even death, and therapy is very different depending on the underlying cause. Additionally, patients may sometimes need urgent intervention or surgery. Thus, it is essential to quickly discriminate the etiology and start appropriate therapy. This review highlights the pathogenesis, clinical and laboratory manifestation, differential diagnosis, and treatment of antithrombotic drug-induced thrombocytopenia in cardiovascular diseases.

Glycoprotein IIb/IIIa inhibitor-induced thrombocytopenia

Thrombocyte glycoprotein IIb/IIIa inhibitors prevent fibrinogen binding and thereby thrombocyte aggregation. The inhibition of thrombocyte activation at the damaged coronary plaque is the target of the new therapeutic strategies in treating acute coronary syndrome. This reduces the ischemic complications associated with the non-STelevation myocardial infarction (NSTEMI) and percutaneous coronary intervention (PCI). Thrombocytopenia is a known complication of glycoprotein (GP) IIb/IIIa inhibitors. Although, in general, GP IIb/IIIa inhibitor-induced thrombocytopenia is a harmless side effect which responds readily to thrombocyte transfusion, it can occasionally be a very serious complication associated with serious bleeding. In addition patients developing thrombocytopenia have unfavorable outcome (e.g., death, myocardial infarction, bypass surgery or additional PCI) in comparison to patients without thrombocytopenia. Advanced age (> 65 years), low BMI and a low initial thrombocyte count (<180,000/microl) are independent risk factors of thrombocytopenia. The risk of bleeding is higher with this form of thrombocytopenia not only due to the low thrombocyte count but also to the impaired function of the remaining thrombocytes. It is important to closely monitor platelet count during GP IIb/IIIa antagonist treatment. Platelet count monitoring two, six, twelve and 24 hour after starting the treatment reveals most cases of acute thrombocytopenia. Side effects can be avoided by the early discontinuation of the GP IIb/IIIa antagonist treatment. This article reviews the diagnosis and treatment of glycoprotein IIb/IIIa inhibitor-induced thrombocytopenia and summarizes the differential diagnosis from heparin-induced thrombocytopenia and laboratory-related pseudothrombocytopenia.

Immune thrombocytopenia caused by glycoprotein IIb/IIIa inhibitors

Agents that react with the platelet glycoprotein (GP) IIb/IIIa complex (alphaIIb/beta3 integrin) to block fibrinogen binding and platelet-platelet aggregation have been proved to be effective in reducing the incidence of complications following coronary angioplasty and are now widely used for this purpose. Acute thrombocytopenia, which is sometimes severe and life-threatening, is a recognized side effect of this class of drugs. In contrast to other types of drug-induced thrombocytopenia, this complication can occur within a few hours of a patient's first exposure to the medication. Accumulating evidence has indicated that drug-dependent antibodies, which can be naturally occurring, are the cause of platelet destruction in such individuals. In this review, we will consider the clinical aspects of thrombocytopenia resulting from sensitivity to GPIIb/IIIa inhibitors and will review evidence that the platelet destruction is antibody-mediated.

Integrin αIIbβ3 specific synthetic human monoclonal antibodies and HCDR3 peptides that potently inhibit platelet aggregation

The interaction of fibrinogen with integrin alphaIIbbeta3 (GPIIb/IIIa), in part mediated by an RGD tripeptide motif, is an essential step in platelet aggregation. Based on their inhibition of platelet aggregation, three integrin alphaIIbbeta3 inhibitors are clinically approved. The clinically most widely used integrin alphaIIbbeta3 inhibitor abciximab is a chimeric mouse/human antibody that induces thrombocytopenia, often severe, in 1-2% of patients due to a human anti-mouse antibody (HAMA) response. In addition, unlike other ligands mimicking small molecular drugs, abciximab cross-reacts with integrin alphavbeta3 and alphaMbeta2. Here we used phage display to select monoclonal antibodies specific to integrin alphaIIbbeta3 from a synthetic human antibody library based on the randomized HCDR3 sequence VGXXXRADXXXYAMDV. The selected antibodies revealed a strong consensus in HCDR3 (V(V/W)CRAD(K/R)RC) and high specificity toward integrin alphaIIbbeta3 but not to other RGD binding integrins such as alphavbeta3, alphavbeta5, and alpha5beta1. The selected antibodies as well as three synthetic peptides (VWCRADRRC, VWCRADKRC, and VVCRADRRC) whose sequences were derived from the HCDR3 sequences of the selected antibodies strongly inhibited the interaction between integrin alphaIIbbeta3 and fibrinogen and platelet aggregation ex vivo. To our knowledge, these are the first fully human monoclonal antibodies that are specific to integrin alphaIIbbeta3 and can potently inhibit platelet aggregation.