ACTIVATED PROTEIN-C RESISTANCE AND THE FACTOR-V-LEIDEN MUTATION IN CHILDREN WITH THROMBOSIS

To determine the prevalence of activated protein C resistance and the factor V Leiden mutation (position 1691, arginine 506 to glutamine sub stitution) in children with thrombosis, plasma samples from children w ith thrombosis were tested for activated protein C resistance. DNA was analyzed for the factor V Leiden mutation, Five of 34 children (15%) had activated protein C resistance; each was heterozygous for the fact or V Leiden mutation, All 5 children heterozygous for the factor V Lei den mutation suffered non-CNS venous thromboses comprising 21% of the group of children (5/24) with non-CNS venous thrombotic events, Each o f these 5 children had a family history of thrombosis, In conclusion, children with non-CNS venous thrombosis should be evaluated for the fa ctor V Leiden mutation, Children most likely affected are those with a family history of thrombosis. (C) 1998 Wiley-Liss, Inc.