Heterozygous factor VII deficiency and severe hemophilia A in the same kindred.

The association between heterozygous factor VII deficiency and severe hemophilia A in the same family is described. The 18-year-old proposita had a negative personal history for bleeding events and underwent clotting evaluation after a fortuitous finding of a prolonged PT. Decreased levels of both factor VII activity and antigen to about 50% of normal, compatible with heterozygous deficiency, were found in her and in three other asymptomatic siblings. Two uncles on the paternal side had severe hemophilia A and also showed low factor VII levels. However, in these two patients factor VII deficiency was secondary to chronic liver disease due to hepatitis B and C virus infections. Combined clotting defects in the same kindred may be due to an independent segregation of two separate defects or to common gene(s) malfunction. Factor VII deficiency is frequent and probably underestimated in the general population. For these reasons factor VII deficiency can easily segregate with other clotting defects.