Factor VIIa and antithrombin III activity during severe sepsis and septic shock in neutropenic patients.

Abstract

Septic shock and multiple organ failure may be associated with coagulation activation, disseminated fibrin formation, and consumption of coagulation inhibitors such as antithrombin III. We have evaluated prospectively coagulation measurements in patients with severe chemotherapy-induced neutropenia. This group of patients was chosen because of their high risk of developing severe septic complications, thus allowing serial prospective coagulation testing before and during evolving sepsis or septic shock. Sixty-two patients with febrile infectious events were accrued to the study. Of these, 13 patients progressed to severe sepsis and 13 additional patients to septic shock as defined according to standard diagnostic criteria. At the onset of fever, factor (F) VIIa activity, FVII antigen and antithrombin III (AT III) activity decreased from normal baseline levels and were significantly lower in the group of patients who progressed to septic shock compared with those that developed severe sepsis (medians: 0.3 v 1.4 ng/mL, 21 v 86 U/dL and 45% v 95%; P < .001). The decrease of these measurements in septic shock was accompanied by an increase in prothrombin fragment 1+2 (median: 3.6 v 1.4 nmol/L; P = .05), a marker of thrombin generation. These differences were sustained throughout the septic episode (P < .0001). FVIIa and AT III levels of < 0.8 ng/mL and < 70%, respectively, at onset of fever predicted a lethal outcome with a sensitivity of 100% and 85%, and a specificity of 75% and 85%, respectively. In contrast, FXIIa-alpha antigen levels were not different between groups at onset of fever but increased modestly during the course of septic shock (P = .001). Thus, septic shock in neutropenic patients is associated with increased thrombin generation. Furthermore, both FVIIa and AT III measurements are sensitive markers of an unfavorable prognosis.