[A study of coagulation contact factors in hereditary angioneurotic oedema (author's transl)]

Coagulation contact factors were studied in 9 patients with hereditary angioneurotic oedema. After storage of the plasma at O degrees C for 20 hours, activation of prekallikrein and factor VII, together with prekallikrein consumption, were observed. The cold activation, due to deficiency of C1 esterase inhibitor, was not suppressed by polybren in vitro (factor XII activation inhibitor) but was prevented by aprotinins (kallikrein inhibitors). These findings would suggest that patients with hereditary angioneurotic oedema should be investigated for prekallikrein consumption and should be treated with aprotinin as soon as the attack begins.