ABNORMAL VIII - VONWILLEBRAND-FACTOR PATTERNS IN THE PLASMA OF PATIENTS WITH THE HEMOLYTIC-UREMIC SYNDROME

  • 1 January 1984
    • journal article
    • research article
    • Vol. 64  (3) , 592-598
Abstract
Plasma VIII:von Willebrand factor antigen (VIII:vWF) levels were elevated .apprx. 2- to 8-fold in 7 patients (3 adults and 4 children) during acute episodes of thrombocytopenia, renal failure and hemolytic anemia (the hemolytic-uremic syndrome, HUS). In all 7 patients, there was an alteration in plasma VIII:vWF patterns during these acute HUS episodes, so that the largest VIII:vWF forms were relatively decreased. Plasma VIII:vWF multimer patterns returned to normal, or nearly to normal, as platelet counts returned to preexisting levels, even in the patients whose recovery of renal function was incomplete and whose plasma VIII:vWF antigen level remained above normal. The sister of 1 of the HUS patients had a similar clinical prodrome (gastroenteritis) that was not followed by thrombocytopenia or renal failure and was not accompanied by an elevated level or abnormal forms of plasma VIII:vWF. An alteration in VIII:vWF metabolism, distribution or interaction with platelets apparently is associated with acute HUS episodes. In contrast to patients with chronic relapsing thrombotic thrombocytopenic purpura, none of the HUS patients (either during or after the acute HUS episodes) had a defect in the conversion of unusually large VIII:vWF multimers derived from endothelial cells to the VIII:vWF forms found in normal plasma.