Title: Stuart Clotting Defect. I. Segregation of an Hereditary Hemorrhagic State from the Heterogeneous Group Heretofore Called “Stable Factor” (SPCA, Proconvertin, Factor VII) Deficiency
Abstract: In 1951, Alexander, Goldstein, Landwehr, and Cook (1) described a patient with a congenital hemorrhagic diathesis of an unusual type.There was a normal prothrombin concentration, but a prolonged prothrombin time which could be corrected by serum and serum fractions but not by BaSO4-adsorbed plasma or serum.The clotting factor deficient in the plasma of this patient dif- fered, therefore, from prothrombin, Factor V, ac- celerator globulin (Ac-G), and antihemophilic factor (AHF).The normal analogue of the factor deficient in this patient was relatively heat stable, adsorbable by barium sulphate and diminished in dicoumarol plasma.The patient was believed to lack the precursor of SPCA (serum prothrombin conversion accelerator) a factor which had been studied previously (2).Independently in 1951, Koller, Loeliger, and Duckert (3) and Owren (4) recognized the presence of clotting factors designated Factor VII and proconvertin, respectively.These two factors were believed to be identical with each other and with SPCA.Although the three terms have been used synonymously since that time, the literature shows no evidence that the identity has been rigor- ously established.Since the case of Alexander, Goldstein, Landwehr, and Cook (1), 29 other cases (Table I) of a congenital deficiency of these presumably identical factors have been described (5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20)(21)(22)(23)(24).Our present studies indicate that the patient of Crockett, Shotton, Craddock, and Leavell (25) also belongs in the same group.The thromboplastin generation test has been performed on 16 of the 31 patients.It has been normal in six, abnormal in nine, and questionable in one (see Table I).This suggests that the cases diagnosed as Factor VII deficiency, SPCA defi-