ASYMPTOMATIC vWD VARIANT WITH ABSENT RISTOCETIN ACTIVITY BUT PRESERVED BOTROCETIN ACTIVITY AND A DAUGHTER WITH TYPE III (HOMOZYGOUS) vWD

The propositus, female aged 1 year, was investigated because of severe bruising. Bleeding time (BT) was in excess of 20 mins, VIIIC Multimeric analysis was not possible on the propositus, but was normal in the plasma of all other family members. The father of the propositus, however, had an abnormal multimer pattern on lysed platelets, in that the faint low molecular weight doublet is absent and a dense band in the position of the lower band of the doublet with anodal and cathodal trailing.The maternal grandmother and mother appear to have asynpto-matic type I vWD and the father possibly has asymptomatic type I together with an alteration in the biologically vWF site with loss of the ristocetin site. This abnormality is not seen in his parents and his daughter possibly has type III vWD. The propositus' father although having some similarities to the patient of Howard et al., is different in other aspects.1. Howard MA, Salem HH. et al. (1982) Variant von Willebrand's disease Type B - Revisited. Blood, 60: 1420-1428.