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Updated: Mar 21, 2026

Investigating von Willebrand Factor Pathophysiology Using a Flow Chamber Model of von Willebrand Factor-platelet String Formation
Published on: August 14, 2017
[Acquired von-Willebrand factor and factor-VIII deficiencies caused by angiostrongylosis in a dog]
Lisa Hausmann1, Alexander Pack, Sylvia Hausmann
1Lisa Hausmann, Klinik für Kleintiere, Innere Medizin, Justus-Liebig-Universität Gießen, Frankfurter Straße 126, 35392 Gießen,
Abstract:
An 8-year-old male Australian Shepherd was presented with bleeding from the lip and hemoabdomen. Hematology demonstrated marked thrombocytopenia and anemia. Abdominal ultrasound followed by laparotomy did not detect the cause of bleeding. Plasma transfusion resulted in temporary stabilization. Severe von-Willebrand factor deficiency and factor-VIII deficiency were diagnosed. After subsequent bleeding episodes, infection with Angiostrongylus vasorum was found in both a fecal parasitological examination and by PCR from EDTA-blood. Following successful therapy with fenbendazole, von Willebrand factor and factor VIII were within the normal range. This is the second case report of an acquired von-Willebrand-factor deficiency associated with Angiostrongylus-vasorum infection in a dog, and the first case report with concurrent factor-VIII deficiency.
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