Abstract
The biochemical and biological properties of antithrombin III (AT III) and the clinical consequences of a deficiency of this inhibitor are described. Therapy with concentrates of purified AT III has been carried out for about 10 years and the present experience is reviewed. In a relatively small number of patients with congenital AT III deficiency it is necessary, under certain condition to substitute AT III. A considerably more frequent use of AT III concentrates has been made in acquired AT III deficiency, especially in shock and diffuse intravascular coagulation (DIC). This therapy was shown to be promising since the duration of DIC could be considerably shortened and the frequency of fatal events could be significantly diminished. No undesirable side effects of substitution with virus-sterilized AT III concentrates have been hitherto observed.