While deficiency is rare, two forms exist. Both are autosomal recessive and affect both sexes. In one form the VII molecules are decreased while in the second group an abnormally formed molecule is produced. Bleeding symptoms may be severe in homozygotes and include epistaxis, ecchymoses, GI bleeding, hemarthroses, menorrhagia, and umbilical cord hemorrhage. Fatal cerebral hemorrhage may occur.
Heterozygotes are usually asymptomatic.
If only Coagulation studies are being drawn, draw 1-2 mL, discard, and collect Coagulation studies. This procedure avoids contamination of specimen with tissue thromboplastin. Call Client Services for instructions. Blood may be used from an arterial line or line flush with heparin providing the first 15 mL blood is drawn off before Coagulation studies are drawn. Please indicate such specimens.