Protein C (PC) deficiency associated with hereditary venous thromboembolic disease was first reported in 1981 and is inherited as an autosomal dominant disorder. The prevalence of heterozygous PC deficiency is estimated to be 1 to 4% in venous thrombotic diseases. The homozygous PC deficiency is even rare, and has been reported in only about 10 families througout the world. It usually presents in newborn infants as purpura fulminans or severe thrombotic disease. We herein report two newborn brothers in a Chinese family, who manifested with purpura fulminans soon after birth and died at age of 21 days and 27 days respectively. Vitamin K was administered to the second baby after birth. Both parents are not consanguineous and there were no family histories of thromboembolism on paternal and maternal sides. Blood sample was not available for specific studies in the first baby. PC antigen level by electroimmunoassay was <6% in the second baby and 49% and 60% respectively in their mother and father. Antithrombin III activity by amidolytic method was 49% in the second baby, and 90% and 97% respectively in their mother and father. Vitamin K-dependent coagulation factors and factor V were within the expected range for a newborn. Factor VIII and fibrinogen level were notably decreased. Autopsy findings of the two newborns demonstrated the similar pictures characterized by fibrin thrombi in blood vessels causing extensive hemorrhagic infarts of skin, lung, liver, kidneys, testis, urinary bladder, esophagus and brain. Our Data indicate that neonatal purpura fulminans can be familial and caused by severe homozygous PC deficiency.
Neonatal asphyxia and renal failure as the presentation of non-inherited protein C deficiency