DIAGNOSIS OF VON-WILLEBRANDS DISEASE SUBT YPES BY ANALYSIS OF MULTIMERIC COMPOSITION OF PLASMA VON-WILLEBRAND-FACTOR

The accurate diagnosis of the type of von Willebrand's disease (vWD) i s important for a better understanding of its pathogenesis and for ade quate treatment decision. We assessed the usefulness of the analysis o f the multimeric composition of von Willebrand factor (vWF) in the dia gnosis of vWD variants. vWF is purified by gel filtration and policlon al, heterologous antibodies are raised in rabbits, which are immunopur ified and radioiodinated. These are used to reveal, by autorradiograph y, the bands of vWF of various molecular weights separated by electrop horesis in agarose gels. This procedure reveals that 74 (80%) out of 9 2 patients with vWD suffer the classic type (I) of the disease, 6 (6.5 %) type as IIA, 6 (6.5%) as IIB and 6 (6.5%) as III. The test is neces sary for the correct classification of the patients, but is complex, l aborious and expensive; it should be performed in patients with high p robability of vWD or after the generic diagnosis of vWD has been made.