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Updated: Aug 18, 2026

Investigating von Willebrand Factor Pathophysiology Using a Flow Chamber Model of von Willebrand Factor-platelet String Formation
Published on: August 14, 2017
Von Willebrand factor-cleaving protease activity remains at the intermediate level in thrombotic thrombocytopenic
Takeshi Sugimoto1, Katsuyasu Saigo, Tomohiro Shin
1Hematology Oncology Division, Department of Medicine, Hyogo Medical Center for Adults, Akashi, Japan.
Abstract:
A 59-year-old woman, diagnosed with chronic myelogenous leukemia (chronic phase) and treated with interferon-alpha for 13 years, developed renal failure. Renal biopsy showed thrombotic thrombocytopenic purpura, but intensive therapy including plasma exchange and steroid administration was not effective. The activity of von Willebrand factor-cleaving protease was detectable at the intermediate level (15-46%) during the clinical course, suggesting that this case was not compatible with the previously reported pattern of idiopathic or drug-induced thrombotic thrombocytopenic purpura, but with the pattern associated with malignant disease or immunological disorders. Further studies to determine the effects of interferon-alpha on endothelial cells in chronic myelogenous leukemia patients are needed.
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