Effect of prothrombotic mutations on factor consumption in children with hemophilia.

INTRODUCTION: In hemophilia A, factor activity usually correlates with clinical severity; however, there are patients with severe hemophilia who have bleeding less than expected. AIM: The aim of this study is to evaluate the impact of prothrombotic mutations on annual factor consumption in children with hemophilia. METHODS: Factor V Leiden (FVL) G1691A, Prothrombin (PT) G20210A and methylenetetrahydrofolate reductase (MTHFR) C677T and A128C mutations were evaluated in children with moderate-severe hemophilia A (n = 51) and controls (n = 25). RESULTS: None of the cases and controls carried the FVL and PT G20210A in homozygous state. There was no difference in factor consumption between carriers of FVL, PT mutations, and noncarriers. Patients who were homozygous for MTHFR C677T were found to have increased factor consumption compared to noncarriers, and this was a negative association. No decrease in factor consumption was noted in patients with hemophilia having MTHFR A1298C mutation. CONCLUSION: We could not demonstrate a significant decrease in factor concentrate consumption in children with hemophilia having prothrombotic mutations.