Plasmatic prekallikrein, factor XII, factor XI, C1-inactivator and alpha(2)-macroglobulin were evaluated in myeloma patients. Results suggest no modification in the contact phase since there was no significant difference between patients and controls. Other parameters of blood coagulation and fibrinolysis (APTT, TT, fibrinogen, factor V, ELT and LAFP) gave findings consistent with those described in the literature.342201203