CHARACTERIZATION OF 2 CASES OF ACQUIRED TRANSITORY VON-WILLEBRAND SYNDROME WITH CIPROFLOXACIN - EVIDENCE FOR HEIGHTENED PROTEOLYSIS OF VON-WILLEBRAND-FACTOR

We characterized the cause of two cases of transitory acquired von Wil lebrand syndrome associated with the administration of ciprofloxacin. Purified Ig from the two patients did not Inhibit Ristocetin Cofactor activity or binding to collagen of normal plasma, ruling out the possi bility of an inhibitor. The analysis of multimeric pattern of plasma v on Willebrand Factor (vWF) showed the lack of larger multimers in both patients, with a relative decrease of all the remaining forms in the first patient. The subunit composition of plasma vWF showed a marked r eduction of the native 225 Kd subunit (31.9% and 32.9%; normal range 7 4-86%) and an increased proportion of the 189, 176, and 140 Kd fragmen ts. These abnormalities disappeared during the follow-up, without any specific therapy. In conclusion, a common pathophysiological basis is demonstrated in both patients, with a heightened proteolysis of plasma VWF by an unknown mechanism. (C) 1995 Wiley-Liss, Inc.