INHERITED RISK-FACTORS FOR THROMBOPHILIA IN CHILDREN WITH NEPHROTIC SYNDROME

A hereditary tendency to venous thrombosis rarely results in a spontan eous thrombotic episode before puberty. The acquired hypercoagulabilit y associated with nephrotic syndrome (NS) could, however, coincide wit h underlying inherited thrombophilia, thereby resulting in a thromboti c event. In order to determine the contribution of inherited prothromb otic conditions to thrombosis in children with NS, we analysed DNA fro m a cohort of patients with NS for the common genetic risk factors of vascular disease. We evaluated 53 children with NS and 41 paediatric c ontrols for prevalence of the factor V mutation Arg506 --> Gin (factor V Leiden), the prothrombin variant (20210G --> A), and homozigosity f or Ala677 --> Val in the methylenetetrahydrofolate reductase gene (MTH FR). Eight thrombo-embolic events were identified in 6 out of 53 (11%) children. Three thrombotic events occurred during NS activity and were associated with systemic infections in two and an arterial puncture i n one. An inherited risk factor was identified in seven children, all without thrombosis (two heterozygous for the prothrombin variant and f ive homozygous for the MTHFR-T). None of the studied inherited risk fa ctors were identified among those with thrombosis. Conclusions These d ata suggest that inherited thrombophilia is not a strong risk factor f or the development of non recurrent thrombosis in children with NS.