Thrombotic disease is less frequent in children than in adults, but may result in severe
morbidity and mortality. The coagulation system is balanced to provide rapid activation to
stop bleeding and appropriate inhibition to prevent unwanted clot extension. It is regulated
by fibrinolysis and by three major anticoagulant pathways: the protein C, antithrombin, and
tissue factor pathway inhibitor systems. Acquired or inherited abnormalities of coagulation
proteins or hemostatic regulatory mechanisms, particularly when combined with dehydration …