Two sisters born from a nonconsanguineous marriage were found to have congenital factor XIII deficiency. In the electroimmunoassay system, using an anti-subunit S antiserum, two distinct peaks or rockets were seen in normal plasma and serum whereas only one peak was present in the propositae plasma or serum. In the bidimensional immunoelectrophoresis system, using the anti-subunit S antiserum, two major peaks were seen in normal plasma whereas only one peak was seen in the propositae plasma. Using an anti-subunit A antiserum no peak or precipitate was seen in our propositae in the electroimmunoassay or in the bidimensional immunoelectrophoresis systems. Both the parents and the children of our two propositae showed a normal coagulation pattern. Therefore, the heredity appears to be autosomal recessive. These data indicate that the defect is characterized by a normal factor XIII subunit S (support) and a lack of factor XIII subunit A (activity)

A patient with a combined hereditary deficiency of factors VII and VIII is presented together with a family study. The main bleeding manifestations were easy bruising and bleeding after tooth extractions. No hemarthrosis was ever observed. The main laboratory features consisted in a mild prolongation of prothrombin time and of partial thromboplastin time. TG test was abnormal and was corrected by the addition of adsorbed normal plasma. Specific assays revealed a moderate defect of factors VII and VIII. All other clotting factors were within normal limits. The factor VII antigen in the propositus was normal or nearly normal. The factor- VIII-associated antigen was also normal. Five additional family members presented the same coagulation pattern and were variably symptomatic. The hereditary transmission pattern seems to be autosomal dominant. The defect appears to be due to a structural abnormality of a gene controlling factors VII and VIII activation.

23 patients with hemophilia B have been investigated by means of several immunological methods. 16 patients (69.9%) had no detectable factor XI antigen. Five had a normal factor IX antigen and the electrophoretic mobility of this abnormal factor IX was similar to that of its normal counterpart. One of these five patients had hemophilia B(m), since ox brain thromboplastin clotting time was severely prolonged. The remaining two patients had reduced or decreased factor IX antigen. Several patients showed a slight prolongation of ox brain thromboplastin time due to an associated slight factor VII deficiency. On the basis of these results, a tentative classification of hemophilia B into five variants is proposed, namely: hemophilia B-, or with no factor IX antigen; hemophilia B+, or with normal factor IX antigen; hemophilia B(ra), or with reduced factor IX antigen; hemophilia B(m), or with normal factor IX antigen and severely prolonged ox brain thromboplastin; hemophilia B, usually B-, with associated mild factor VII defect. A complete evaluation of the hemophilia B patients is feasible only by means of a battery of tests, namely : factor IX activity assay, factor IX antigen determination, ox brain thromboplastin clotting time, factor VII activity assay.

23 patients with hemophilia B have been investigated by means of several immunological methods. 16 patients (69.9%) had no detectable factor XI antigen. Five had a normal factor IX antigen and the electrophoretic mobility of this abnormal factor IX was similar to that of its normal counterpart. One of these five patients had hemophilia Bm, since ox brain thromboplastin clotting time was severely prolonged. The remaining two patients had reduced or decreased factor IX antigen. Several patients showed a slight protongation of ox brain thromboplastin time due to an associated slight factor VII deficiency. On the basis of these results, a tentative classification of hemophilia B into five variants is proposed, namely: hemctor IX antigen; hemophilia Bra, or with reduced factor IX antigen; hemophilia Bm, or with normal factor IX antigen and severely prolonged ox brain thromboplastin; hemophilia B patients is feasible only by means of a battery of tests, namely:factor IX activity assay, factor IX antigen determination, ox brain thromboplastin clotting time, factor VII activity assay.

Activation of coumarin plasmas in glass tubes for 60 min resulted in a clear shortening of Thrombotest clotting times. Normotest clotting times were shortened too but to a much lesser extent. As a consequence the Normotest (NT)/Thrombotest (TT) discrepancy which was quite large at 0 time, became progressively smaller. This phenomenon was observed both in undiluted and 6:10 diluted plasma. After ellagic acid activation a similar phenomenon was noted even though a less pronounced shortening of Thrombotest was noted. These data suggest that Thrombotest is very sensitive to contact phase and to factor VII activation and not to any coumarin-induced inhibitors.