Factor VII Deficiency

Abstract

The complex formed between the procoagulant serine protease activated factor VII (FVII) and the membrane protein tissue factor, exposed on the vascular lumen upon injury, triggers the initiation of blood clotting. This review describes the clinical picture of FVII deficiency and provides information on diagnosis and management of the disease. FVII deficiency, the most common among the rare congenital coagulation disorders, is transmitted with autosomal recessive inheritance. Clinical phenotypes range from asymptomatic condition, even in homozygotes, to severe disease characterized by life-threatening and disabling symptoms (central nervous system and gastrointestinal bleeding and hemarthrosis), with early age of presentation and the need for prophylaxis. In females, menorrhagia is prevalent and affects two thirds of the patients of fertile age. Although FVII gene mutations are extremely heterogeneous, several recurrent mutations have been reported, a few of them relatively frequent. The study of genotype-phenotype relationships indicates that modifier (environmental and/or inherited) components modulate expressivity of FVII deficiency, as reflected by patients with identical FVII mutations and discordant clinical phenotypes. Several treatment options are available for FVII deficiency: the most effective are plasma-derived FVII concentrates and recombinant activated FVII (rFVIIa). Treatment-related side effects are rare.