Related Experiment Video
Updated: May 24, 2025

A Uniform Shear Assay for Human Platelet and Cell Surface Receptors via Cone-plate Viscometry
Published on: June 5, 2019
Management challenge of a rare concomitant platelet glycoprotein IV/CD36 and IIb/IIIa deficiencies: Case illustration
Tro Sekayan1, Elizabeth S Allen2, Patricia Kopko2
1Department of Medicine, Division of Hematology/Oncology, University of California San Diego, San Diego, California, USA.
Introduction/Background:
Platelet membrane glycoproteins (GPs) serve several functions, the most significant of which is their role in primary hemostasis. Among these, GP IIb/IIIa is the primary fibrinogen receptor and is essential for platelet aggregation. Its deficiency or dysfunction impairs platelet aggregation, leading to Glanzmann thrombasthenia, a rare autosomal recessive bleeding disorder. In contrast, platelet GP IV (CD36) has a limited role in primary hemostasis. While also rare, CD36 deficiency has a disproportionately higher prevalence in individuals of East Asian, African, and Arabian descent. Patients with platelet GP deficiencies can develop antibodies against the missing GPs, leading to immune-mediated platelet transfusion refractoriness (PTR). Consequently, they are unresponsive to platelet transfusions when mostly needed.
Case Presentation:
Here we present the case of an Egyptian male with a lifelong history of an incompletely characterized bleeding disorder who presented for pre-surgical evaluation. We diagnosed the patient with Type I Glanzmann thrombasthenia. Further evaluation revealed anti-CD36 antibodies, leading to the discovery of a concurrent platelet CD36 deficiency. The dual GP deficiency significantly complicated his management, as finding crossmatch-compatible platelets was challenging due to the rarity of CD36-deficient blood donors in the United States.
Discussion/Conclusion:
Awareness of coexisting platelet disorders and their ramifications is limited, mostly because these are stochastically rare (~1 in 100 million for the present case). This case highlights the importance of thoroughly evaluating platelet glycoprotein deficiencies, particularly in individuals with severe bleeding disorders and from ethnic backgrounds with a predisposition to specific platelet disorders. Such an approach can prevent future platelet antibody formation or reduce bleeding risk with pre-existing antibodies.
Related Concept Videos
Antiplatelet Drugs: Prostaglandin Synthesis, P2Y12 and Glycoprotein IIb/IIIa Inhibitors
Prostaglandin synthesis inhibitors, exemplified by the widely known aspirin, wield their power by irreversibly acetylating...
Disorders of Hemostasis
Thromboembolic Disorders
Two factors primarily cause thromboembolic conditions.
Formation of the Platelet Plug
As the injured blood vessel contracts, endothelial cells undergo contraction, revealing collagen fibers in the basement membrane and underlying connective tissue. Furthermore, the plasma membrane of endothelial cells becomes adhesive, preparing the site for platelet adhesion. Platelets...
Anticoagulant Drugs: Low-Molecular-Weight Heparins
Structure and Function of Platelets
Platelets are continually replenished, circulating in the bloodstream for 9-12 days before being removed by phagocytes, primarily in the spleen. A microliter of circulating blood contains between 150,000 and 450,000...
Esophageal Varices-II: Clinical Features and Management
In the initial assessment, a thorough review of the patient's medical history is vital to identify risk factors such as liver disease, alcohol...

