title: Desmopressin-induced thrombocytopenia in type I platelet discordant von Willebrand disease.
abstract: Thrombocytopenia after desmopressin (DDAVP) infusion is usually observed in patients with type IIB von Willebrand disease (vWD). No other subtypes of vWD with thrombocytopenia after DDAVP have been reported so far. We describe here the occurrence of thrombocytopenia after DDAVP in a 39 year old male and his son with phenotypic characteristics of type I vWD, "platelet discordant subtype." After DDAVP, the abnormal ristocetin cofactor/von Willebrand factor antigen ratio in plasma was not corrected and the bleeding time remained markedly prolonged. Platelet count dropped 30 min after DDAVP (from 279 to 96 x 10(3)/microL in the propositus and from 298 to 116 x 10(3)/microL in his affected son) and returned to normal at 60 min. Platelet clumping was evident on peripheral blood smears obtained after infusion. These cases indicate that after DDAVP thrombocytopenia can occur in vWD other than type IIB.
authors.affiliation: Department of Hematology and Hemophilia, San Bortolo Hospital, Vicenza, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Castaman
authors.forename: F
authors.initials: F
authors.lastname: Rodeghiero
authors.forename: A
authors.initials: A
authors.lastname: Lattuada
authors.forename: P M
authors.initials: PM
authors.lastname: Mannucci
mesh_terms: D000328:Adult; D001792:Blood Platelets / Q000187:drug effects / Q000502:physiology*; D002648:Child; D003894:Deamino Arginine Vasopressin / Q000008:administration & dosage / Q000009:adverse effects* / Q000494:pharmacology; D004591:Electrophoresis, Polyacrylamide Gel; D005260:Female; D006801:Humans; D066298:In Vitro Techniques; D007262:Infusions, Intravenous; D007700:Kinetics; D008297:Male; D012310:Ristocetin / Q000494:pharmacology; D013921:Thrombocytopenia / Q000139:chemically induced*; D014842:von Willebrand Diseases / Q000097:blood*; D014841:von Willebrand Factor / Q000302:isolation & purification* / Q000378:metabolism
chemical_list: D014841:von Willebrand Factor; D012310:Ristocetin; D003894:Deamino Arginine Vasopressin