Induction of leukocytopenia by cytotoxic drugs protects against the generalized Shwartzman reaction induced by endotoxin. To elucidate the relationship between leukocyte number and in haemostatic and fibrinolytic disturbances in human sepsis, we studied 32 septic patients with abnormal leukocyte counts. Twenty patients had sepsis in the setting of leukopenia after chemotherapy for haematological malignancies. Twelve patients with leukocytosis developed sepsis associated with benign disorders. Concentrations of thrombin-antithrombin III complex (TAT), plasminogen activator inhibitor-1 (PAI-1) and plasma thrombomodulin (TM) in the leukocytosis group of (12.0 +/- 11.0, 40.2 +/- 27.0 and 5.5 +/- 2.3 ng/ml, respectively) were significantly elevated compared to the leukopenia group of (3.8 +/- 2.3, 18.0 +/- 15.0 and 3.1 +/- 1.0 ng/ml, respectively) and controls (3.3 +/- 0.4, 10.5 +/- 5.3, 3.0 +/- 0.5 ng/ml, respectively). On the other hand, there were no significant differences in these values between leukopenia group and controls. Thus leucocytes may play important roles in thrombin generation, PAI-1 release and injury to endothelial cells.
