Molecular subunits and transamidase activity of factor XIII in patients with deep vein thrombosis.

Thrombin formed during the clotting process leads to the activation of factor XIII and then to its consumption. Transamidase activity of factor XIII and its concentrations of subunits "a" and "b" were measured in plasmas of patients with deep vein thrombosis of the calves. The patients revealed a significant decrease of both factor XIII activity and its concentration of subunit "a". A subsequent rise of transamidase activity and concentration of subunit "a" of factor XIII to the normal values was observed in two weeks' time. It is assumed that estimation of factor XIII activity and/or its concentration of subunit "a" may be an additional method for detecting venous thrombosis and monitoring its therapy.