The use of recombinant factor VIIa in children with inherited platelet function disorders

Inherited deficiencies of platelet surface glycoproteins such as Glanzmann's thrombasthenia (GT) or Bernard-Soulier syndrome (BSS) can lead to a severe bleeding diathesis. In the past, bleeding episodes in these patients have often required platelet transfusion to secure haemostasis but recently a number of patient reports have suggested that recombinant factor VIIa (rVIIa) may also be effective. We have used rVIIa on 33 occasions in seven children with inherited platelet function disorders over a 2-year period: five had GT, one had BSS and one had storage pool disease with a severe phenotype. Bleeding ceased with rVIIa alone in 10 of 28 acute bleeding episodes, but recurred in two of these. The two features that predicted response to rVIIa were the severity of the bleeding and the delay from the onset of bleeding to treatment. Five episodes of planned surgical intervention were treated successfully with rVIIa. Eighteen out of the 28 acute episodes and none of the planned surgical episodes required blood product support. We have found variable efficacy of rVIIa for acute bleeding episodes in this small series of children with inherited platelet function defects but larger studies are warranted, particularly as rVIIa is a relatively low-risk treatment approach for these disorders.