Acquired Platelet Dysfunction—Laboratory and Clinical Implications

In contrast to congenital platelet disorders, which are rare, acquired thrombocytopenia and platelet dysfunction are both frequently encountered in clinical practice. The usual clinical manifestations are mucosal bleeding, epistaxis, and superficial epidermal bleeding, generally of modest extent. However, when the patient is exposed to a hemostatic challenge (e.g., surgery), impaired platelet dysfunction or thrombocytopenia might impose a substantial bleeding risk. The main cause of platelet dysfunction is the use of antiplatelet drugs, but more importantly, systemic disorders have long been recognized as contributors to platelet dysfunction and/or thrombocytopenia and thereby increased bleeding risk. In this issue of Seminars of Thrombosis and Hemostasis, our invited contributors share their expertise on thrombocytopenia and acquired platelet dysfunction within several very different clinical entities, outside the use of antiplatelet drugs. Strategies are presented on how to diagnose and treat patients with thrombocytopenia and/or acquired platelet dysfunction to optimize patient care.