title: Atypical variant of acquired von Willebrand syndrome in Wilms tumor: is hyaluronic acid secreted by nephroblastoma cells the cause?
abstract: Acquired von Willebrand syndrome (AvWS) has been reported in eight children with Wilms tumor (nephroblastoma in four boys and four girls) at a mean age of 3.3 years (range, 0.33-9 years). Only three of eight patients with AvWS in Wilms tumor presented with mild mucocutaneous bleeding symptoms. The AvWS in seven children with Wilms tumor featured either undetectable or very low von Willebrand factor antigen (vWF.Ag) levels (mean, 3%) and decreased values for vWF ristocetin cofactor (RCF) activity (mean, 20%) and factor VIII coagulant (VIIIc) activity (mean, 16%). The response to 1-desamino-8-arginine vasopressin (DDAVP) was good in two and poor in one patient. Multimeric analysis of the vWF showed a normal pattern of type I von Willebrand disease (vWD) in three patients and an absence of multimers consistent with type III vWD in two patients. The higher functional levels, as compared with antigen levels, with increased ratios for factor VIIIc/vWFAg (mean, 5.3) and vWF.RCF/vWF.Ag (mean, 6.6) in seven patients with Wilms tumor are unexplained physiologically and are not consistent with type I vWF deficiency. The absence of vWD in the patient's family, and the return of factor VIII-vWF parameters to normal after chemotherapy or surgical removal of the Wilms tumor, support the diagnosis of AvWS causally related to the Wilms tumor. The causative agent is thought to be hyaluronic acid secreted by nephroblastoma cells of the Wilms tumor. Prospective studies to determine the nature of AvWS in children with Wilms tumor are warranted.
authors: Clinical Hemostasis and Thrombosis, Department of Hematology, University Hospital Antwerp, Belgium. postbus@goodheartcenter.demon.nl
authors: J
authors: J
authors: Michiels
authors: W
authors: W
authors: Schroyens
authors: Z
authors: Z
authors: Berneman
authors: M
authors: M
authors: van der Planken
mesh_terms: D002648:Child; D002675:Child, Preschool; D003894:Deamino Arginine Vasopressin / Q000008:administration & dosage; D005169:Factor VIII / Q000008:administration & dosage / Q000187:drug effects / Q000378:metabolism; D005260:Female; D014644:Genetic Variation; D006470:Hemorrhage / Q000188:drug therapy / Q000209:etiology; D006801:Humans; D006820:Hyaluronic Acid / Q000378:metabolism; D007223:Infant; D008297:Male; D009447:Neuroblastoma / Q000378:metabolism; D016896:Treatment Outcome; D009396:Wilms Tumor / Q000150:complications* / Q000473:pathology / Q000601:surgery; D014842:von Willebrand Diseases / Q000150:complications* / Q000188:drug therapy / Q000209:etiology; D014841:von Willebrand Factor / Q000187:drug effects / Q000378:metabolism
chemical_list: D014841:von Willebrand Factor; D005169:Factor VIII; D006820:Hyaluronic Acid; D003894:Deamino Arginine Vasopressin