We report our clinical experience in the immune tolerance (IT) therapy of 21 paediatric haemophiliacs with FVIII inhibitor: high responders (16HR) received initially FVIII twice daily at a dosage of 50-300 U/kg/day, 11/16 received a concomitant treatment with activated prothrombin complex concentrate (100-200 U/kg/day). Low responders (five LR) received 20-100 FVIII U/kg every second or third day. Inhibitor elimination was achieved in 19/21 patients in a median time of 4 months in HR and 1.5 months in LR. The outcome and length of time needed to induce IT was significantly correlated with FVIII exposure between the first inhibitor detection and onset of IT therapy and to interruption of IT therapy. For a rapid elimination of FVIII inhibitors it is important to start continuous administration of high-dose FVIII (≥ 100 FVIII U/kg/day) before repeated exposure to FVIII, in order to prevent rebooster effects, prolongation of elimination time, and to reduce expense.

In our center, 289 children with von Willebrand’s disease (vWD) have been diagnosed since 1982. The majority of cases (n = 198) were congenital vWD whereas 91 patients suffered from vWD induced by valproate (VPA). We overview bleeding episodes in 45 children and 64 operative procedures requiring therapeutic intervention. The aim of therapeutic and prophylactic procedures in vWD is correcting the hemostatic disorder and normalization of bleeding time. This can be achieved by application of Haemate P leading to an elevation of plasma levels of von Willebrand parameters together with normalization of bleeding time. In patients with vWD type I, DDAVP will be preferred if contraindications can be excluded and efficacy has been shown. Severe bleeding complications could be prevented in a total of 50 surgical procedures in children with vWD type I by prophylactic treatment with DDAVP or Haemate P. Two children initially treated with DDAVP had to be substituted with Haemate P in the follow-up because of continuous bleeding. In type IIa and type III vWD as well as in VPA-induced vWD, the use of Haemate P was essential for sufficient hemostasis in all bleeding and operations. We conclude that Haemate P provides effective bleeding prophylaxis and treatment in all types of vWD except platelet-type.

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