Factor XI deficiency case reports on congenital and acquired Hemophilia C - A case report

Introduction: Factor XI deficiency or hemophilia C is a very rare coagulation factor deficiency, with a global incidence of 1 in 1 million. Although it is an under-recognized entity, it can cause significant bleeding, resulting in life-threatening complications. Materials and Methods: Coagulation parameters were analyzed using a Sysmex CS-2400 coagulation analyzer. Factor XI levels were detected using Factor XI deficient plasma from Siemens. Activated Partial Thromboplastin Time (APTT) testing was performed using Actin FSL from Siemens. Results: Here, we report the two cases of Factor XI deficiency, one genetic and the other a very rare acquired deficiency due to sepsis, detected during the workup of an isolated APTT prolongation. Conclusion: Factor XI deficiency is a rare bleeding disorder that presents as prolonged isolated APTT. Careful clinical evaluation and complete coagulation workup are necessary for the efficient management of patients, which can prevent life-threatening events