Recurrent thromboembolism in infants and children suffering from symptomatic neonatal arterial stroke: a prospective follow-up study.

BACKGROUND AND PURPOSE The present study was performed to evaluate the rate of recurrent symptomatic thromboembolism with respect to prothrombotic risk factors and underlying clinical conditions. METHODS In a series of 215 consecutively enrolled neonates with arterial ischemic stroke (AIS), the factor V G1691A mutation, factor II G20210A variant, methylenetetrahydrofolate reductase (MTHFR) T677T genotype, lipoprotein (Lp) (a), antithrombin, protein C, protein S, and anticardiolipin antibodies (ACA) were investigated. Patient median follow-up was 3.5 years (range, 1 to 8 years). RESULTS During follow-up, 7 infants and children (3.3%) showed recurrent symptomatic thromboembolism (AIS, n=4; venous sinus thrombosis, n=2; deep vein thrombosis of the leg, n=1). The factor V mutation, factor II variant, elevated Lp(a) >30 mg/dL, protein C deficiency, and protein S or antithrombin deficiency were associated with first stroke onset. In 5 of 7 cases (71.4%), prothrombotic risk factors [MTHFR T677T, elevated Lp(a), hyperhomocysteinemia, protein C deficiency] were involved at the time of recurrence. Furthermore, a second thromboembolic event was triggered additionally by underlying diseases (71%), eg, cardiac malformation and immobilization, diarrhea, mastoiditis, and moyamoya syndrome. CONCLUSIONS Data shown here give evidence that symptomatic recurrent thromboembolism is not common in children with neonatal AIS. The risk of a second event, however, is increased when underlying diseases occur and prothrombotic risk factors are involved.