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Updated: Apr 2, 2026

Tail Vein Transection Bleeding Model in Fully Anesthetized Hemophilia A Mice
Published on: September 30, 2021
[Mild hemophilia A fortuitously discovered during Henoch-Schönlein purpura]
B Joly1, R d'Oiron2, C Desconclois3
1Service d'hématologie biologique, hôpital Antoine-Béclère, université Paris 11, Assistance publique-Hôpitaux de Paris, 157, avenue de la Porte-de-Trivaux, 92140 Clamart, France.
Henoch-Schönlein purpura is a common form of immunological vasculitis in children. Hemophilia A is a genetic disorder, inherited in a X-linked recessive pattern, and characterized by spontaneous hemorrhage or prolonged bleeding due to factor VIII deficiency. The clinical signs depend on the severity of factor VIII deficiency. We herein report the case of a 4-year-old boy admitted to the emergency room for typical rheumatoid purpura, associated with a lengthening of aPTT, whose exploration had uncovered mild hemophilia A. Laboratory assays should explore lengthening of aPTT: firstly the presence of lupus anticoagulant without bleeding risk, in an inflammatory context; secondly a deficiency of VWF and one of the factors involved in the extrinsic coagulation pathway associated with bleeding risk.
Henoch-Schönlein purpura is a common form of immunological vasculitis in children. Hemophilia A is a genetic disorder, inherited in a X-linked recessive pattern, and characterized by spontaneous hemorrhage or prolonged bleeding due to factor VIII deficiency. The clinical signs depend on the severity of factor VIII deficiency. We herein report the case of a 4-year-old boy admitted to the emergency room for typical rheumatoid purpura, associated with a lengthening of aPTT, whose exploration had uncovered mild hemophilia A. Laboratory assays should explore lengthening of aPTT: firstly the presence of lupus anticoagulant without bleeding risk, in an inflammatory context; secondly a deficiency of VWF and one of the factors involved in the extrinsic coagulation pathway associated with bleeding risk.
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