Résumé
Acquired factor XI (FXI) deficiency of autoimmune origin is a rare condition, with only a few cases in children having been documented in the literature. In this study, we present a series of four pediatric patients from France who have been diagnosed with FXI deficiency of autoimmune origin and review four cases from the literature. The majority of patients were adolescents, and many had associated autoimmune disorders. The bleeding symptoms manifested as mild or non-existent, and despite the anticipated hemorrhagic phenotype, two patients exhibited thrombotic episodes, one of which was associated with the administration of prophylactic treatment with activated factor VII.
•Acquired factor XI deficiency in children is rare and associated with a low risk of bleeding.•The associated clinical context often increases the risk of thrombotic episodes.•Thrombotic risk must be assessed before using any pro-thrombotic medication.