Blood, 1960, Vol. 15, No. 1, pp. 146-163.
© 1960 American Society of Hematology, Inc.
Congenital Factor VII Deficiency with Normal Stuart
Activity: Clinical, Genetic and Experimental Observations
HENRY G. KUPFER 1,
BERTRAM L. HANNA 1, and
DIXIE R. KINNE 1
1 Departments of Clinical Pathology and Medical Genetics, Medical College
of Virgina, Richmond, Va.
The case of a four year old white girl with a bleeding tendency characterized by the spontaneous occurrence of petechiae, ecchymoses and
hemarthroses is presented. Laboratory studies indicate a deficiency of factor
VII, with normal levels of all other clotting components, and a vascular deficiency possibly related to frequent upper respiratory infection.
Serum from the patient and from four close relatives having reduced levels
of factor VII is shown to correct the abnormal thromboplastin generation of
Stuart factor-deficient serum. The rate of conversion of prothrombin into
thrombin is markedly delayed in the patient’s plasma but essentially normal
in that of other family members. The patient’s prothrombin conversion is
corrected by the addition of normal or Stuart-deficient plasma. The partial
thromboplastin time of the patient is somewhat prolonged.
It is concluded that factor VII deficiency is inherited in this family as an
incompletely recessive autosomal characteristic. The penetrance of the deficiency allele in the heterozygous individual appears to be variable. Analyses
of the distributions of clotting factor levels in the family and in samples
from the normal population indicate that an individual may vary greatly in
his clotting factor levels, the average variation being nearly as great as the
variation among individuals. The magnitude of the variation among siblings
suggests that the penetrance of the factor VII deficiency allele is affected by
extrinsic factors and that the observed population variation does not result
from the occurrence of multiple alleles. It is suggested that sex may be a
factor determining clotting factor levels.
The bleeding of the patient is controlled by transfusion of plasma and by
injection of a plasma preparation called ACC-76 (Behringwerke, Germany),
the latter followed by a transient elevation of blood factor VII.
Submitted on March 11, 1959
Accepted on May 18, 1959
