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

Abstract

Summary. 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.

The use of recombinant factor VIIa in the treatment of bleeding disorders

“…In one series of patients, the use of factor VIIa was reported to be effective in about 48% of patients. 50 …”

Conduta no perioperatório de paciente pediátrico com trombastenia de glanzmann durante adenoidectomia

“…In a large international survey, rFVIIa treatment was found to be effective in 94% of evaluable surgical procedures and in 75% of evaluable bleeding episodes 2 . It is also recommended that treatment should be administered as early as possible: in the report of Almeida et al 5 good or excellent responses were observed in 71% of bleeds treated within 12 hours of onset, but in only 18% of bleeds treated after 12 hours.…”

“…In a study done by Almeida et al 5 , a single dose of 100 µg.kg -1 was given in bleeding episodes of two children with GT, and because of an excellent response, they required no maintenance dose 5 . We also achieved to maintain the adequate homeostasis with early use of a single low-dose rFVIIa such as 60 µg.kg -1 additional to preoperative platelet transfusion in our GT patient.…”

“…Moreover, in total hepatectomy case with a life threatening bleeding unresponsive to platelet transfusion, single bolus dose of 90 µg.kg -1 rFVIIa was successfully used 14 . Several analyses have suggested that early treatment with rFVIIa is particularly beneficial, resulting in improved success rates with lower doses 5,15 .…”

Surgery in patients with inherited bleeding disorders

“…We advise the administration of HLA-matched platelets for these patients wherever possible. One strategy for haemostasis management of conditions such as Glanzmann's thrombasthenia (see below), has been the use of recombinant factor VIIa which exerts at least some of its haemostatic effect through direct activation of coagulation, and which can be effective in some situations [44]. It would not, however be recommended for major surgery in severe disorders [45], as the effects are difficult to predict and assess, and there may be significant associated thrombotic risks.…”