DDAVP treatment in a child with von Willebrand disease type 2M

von Willebrand disease (vWD) type 2M is characterized by the decreased plat elet-dependent function of the von Willebrand factor (VWF) that is not caus ed by the absence of HMW VWF multimers. We report here on a 4-year-old boy with vWD type 2M, who underwent adenotomy and paracentesis after correction of his hemostatic defect by stimulation with DDAVP. The decreased basal le vels of VWF Antigen (Ag), ristocetin cofactor activity (RiCoF) and collagen binding activity (CBA) (32%, 14% and 9% respectively) could be stimulated to maximum levels of 69%, 70% and 95% 2 h post DDAVP administration. DDAVP was administered in a dosage of 0.4 mu g/kg BW intravenously 30 min prior t o surgery. No bleeding occurred intra- and perioperatively. vWF multimer an alysis revealed supranormal multimers with an abnormal satellite banding pa ttern. The typical separation by gel electrophoresis into oligomers with a triplet structure was missing even after stimulation with DDAVP. Thus, the functional hemostatic defect was corrected in this patient after DDAVP admi nistration, although the structural abnormalities of the VWF multimers were still persisting. Conclusion In conclusion, type 2M vWD might be effectively treated with DDA VP administration in cases of elective surgery, dispensing with vWF replace ment by pooled blood products.