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Methods for Quantitative Detection of Antibody-induced Complement Activation on Red Blood Cells
06:29

Methods for Quantitative Detection of Antibody-induced Complement Activation on Red Blood Cells

Published on: January 29, 2014

Activation and inhibition of Hageman factor-dependent pathways and the complement system in uncomplicated bacteremia

E S Kalter, M R Daha, J W ten Cate

    The Journal of Infectious Diseases
    |June 1, 1985
    PubMed

    Levels of components of the contact activation, coagulation, and complement systems and their main inhibitors were measured in 45 critically ill patients during 61 episodes of uncomplicated bacteremia or bacterial shock. Levels of Hageman factor (factor XII), prekallikrein, high-molecular-weight kininogen, factor XI, factor VII, total hemolytic complement, alternative pathway activity, and C3 were within the normal range during uncomplicated bacteremia (n = 29), but during fatal bacterial shock (n = 13) a significant decrease by 40%-50% was observed in all measurements. During nonfatal bacterial shock (n = 19) a moderate decrease was observed in most of these measurements. The capacity of plasma to inactivate kallikrein was significantly higher during bacteremia than during bacterial shock because of a significant increase in the level of C1 esterase inhibitor. Levels of antithrombin III and alpha 2-macroglobulin were below normal in all groups. Thus increased inhibition of the contact activation and complement systems is beneficial during bacteremia.

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