Ticagrelor Increases Platelet-Mediated Staphylococcus aureus Killing, Resulting in Clearance of Bacteremia

Platelets are a critical immune defense against Staphylococcus aureus bloodstream infections. Staphylococcus aureus alpha-toxin is a virulence factor that decreases platelet viability and accelerates platelet clearance. It has been shown that ticagrelor blocks alpha-toxin-mediated platelet injury and resulting thrombocytopenia, protecting mice in a lethal S. aureus sepsis model. We now present the use of ticagrelor as adjunctive therapy in a patient with a S. aureus endovascular infection and thrombocytopenia, associated with restoration of platelet count and bacteremia clearance. Ticagrelor enhanced platelet killing of the S. aureus bloodstream isolate from the treated patient in vitro.