Case 3: Inhibitor Development in a 1-Year Old Boy with Severe FVIII-Deficient Hemophilia

• 1 year-old boy with severe <1% FVIII deficient hemophilia

• Diagnosed via cord blood testing due to family history

–Maternal grandfather and brother (brother has an inhibitor)

–Genetic defect: inversion mutation

• 2 months of age: developed right knee/thigh bleed

–First exposure to factor concentrate

–Required 4 days of infusion

–Complete resolution of bleeding event

• 3 months of age: developed 2nd right knee/thigh bleed

–Required 9 days of infusion

• 6 months of age: admitted to hospital for a 3rd right knee bleed

–Unable to achieve adequate FVIII levels despite continuous infusion of factor FVIII concentrate

–Diagnosed with 6 Bethesda Unit (BU) inhibitor and started on bypassing agents (administered via central line)