Type III von Willebrand’s disease (vWD) is the most severe form of this inherited coag-ulopathy. It is characterized by a defective primary hemostasis, a prolonged bleeding time and a reduced plasma factor VIII/von Willebrand factor (FVIII/vWF) complex and ristocetin cofactor (Rad). Patients affected by type III vWD are not responsive to desmopressin (DDAVP). Re-placement concentrates of FVIII/vWF repre-sent the one useful approach for treatment of this disorder. A rare complication of the dis-
ease is the appearance of alloantibodies against vWF [1], which may induce severe posttransfusional reactions caused by the for-mation of immune complexes leading to acti-vation of the complement system [2]. In this circumstance, the administration of FVIII/vWF concentrates could he hazardous, because immune reactions as well as anaphy-laxis may occur. Our experience concerns 4 siblings af-fected by type III vWD who exhibit homozy-gous deletions of the entire gene [3].
They developed precipitating antibodies against vWF and 3 of the 4 brothers suffered from severe posttransfitsional immune reactions [1, 2]. We dealt with the dilemma of treating the patients for one episode of iliopsoas hemato-ma, one of flank hematoma and multiple den-tal extractions. In four different settings of oral surgery, cryoprecipitate or concentrates containing vWF (Haemate P) with tranex-amic acid were given. On each occasion, pa-tients developed moderate immune reaction, characterized by dyspnca, lumbar pain and glottic edema. This occurred despite treat-ment with corticosteroids.
On the two occa-sions of iliopsoas and flank hematornas, por-cine factor VIII was administered with effec-tive clinical results and without any adverse reactions, due to its low content of residual vWF.
In a case report by Bergamaschini et al. [4] recombinant FVIII was also given to a female with severe vWD with inhibitor undergoing a major surgical procedure, who had suffered from anaphylaxis after the injection of FVII I/ vWF concentrate. A good clinical outcome was obtained [4]. Majumdar et al. [5] de-scribed the efficacy Of the recombinant factor Vila (rFV11a) together with a high purity vWF concentrate in a woman affected by type III vVvD associated with acquired hemophil-
ia, who underwent hip replacement surgery. In the light of these considerations the use of rFVlIa seemed lobe an alternative hemostat-ic approach in 2 of our patients who had to undergo multiple dental extractions.
Patients and Methods
Case I GM., a 15-year-old male [factor VII coagulant activity (FV1I I:0 2%; vWF <5%; RCM’ <5%; bleed-ing time >30 min], needed oral surgery because of two necrotic roots at sites 36 (left first molar) and 46 (right first molar) (fig. 1). In the past the most important bleeds were muscle hematomas and recurrent episodes of gingival bleeding.
On the occasion of the first bleed-ing, cryoprecipitate was given without any reaction. Subsequently on another occasion, because of a large flank hematoma, porcine factor VIII was infused with-out any discomfort for the patient. Washed packed red cells were used in order to restore the heniatocrit when-ever it decreased below 30%. Because of these treat-ments, the patient developed a low level of inhibitor against VWF.
Al the time of dental extractions the titer of vVVF inhibitor was 3 U/ml. Washed packed red cells (300 nil) were given before because of anemia. Antibi-otic therapy was administered over a period of 1 week before the Operation with the aim of treating the pen-apical abscesses complicated by fistulas.
Keywords:
Von Willebrand’s disease
Inhibitor
Recombinant factor VIla
Oral surgery
Treatment
Authors
N. Ciavarellaa, M. Schiavonia, E. Valenzanoa, F. Manginib, F. Inchingolob
aServizio di Coagulazione, Centro Emofilia,
bClinica Odontoiatrica, Policlinico-Università, Bari, Italia
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