Theodore Earl Warkentin MD, FRCPC, FACP, FRCP

Dr. Theodore Warkentin, MD, BSc(Med), FRCP(C), FACP, is a clinical and laboratory hematologist and transfusion medicine director at Hamilton General Hospital, and is a Professor in the Department of Pathology and Molecular Medicine, and the Department of Medicine, at McMaster University, in Hamilton, Ontario, Canada.

Warkentin's clinical work and related research focus on acquired thrombocytopenias and coagulopathies—most notably the topics of “heparin-induced thrombocytopenia (HIT)” and "ischemic limb gangrene with pulses" (symmetrical peripheral gangrene/purpura fulminans associated with critical illness). Dr. Warkentin devised the “4Ts”, a widely used scoring system for evaluating the clinical probability of HIT. He is a co-winner (with Prof. John Kelton) of the 2015 Prix Galien Canada Prize, the highest award for Canadian scientists who have made significant advances in pharmaceutical research.

Warkentin also identified “spontaneous HIT syndrome” (a rare HIT-mimicking disorder that occurs despite absence of preceding heparin exposure), and other examples of “autoimmune HIT”—a group of unusual clotting disorders that provides insight into “vaccine-induced immune thrombotic thrombocytopenia (VITT),” a novel prothrombotic anti-PF4 platelet-activating disorder that rarely is caused by adenoviral vector vaccines.