The Use of Recombinant FXIII in a Major Acute Bleeding Episode of a Patient with Congenital FXIII Deficiency – the First Experience

Introduction : congenital FXIII deficiency is a rare bleeding disorder with a high risk of spontaneous intracranial haemorrhage. Life-long preventive supplementation is mandatory if FXIII activity is <1%. A novel recombinant FXIII concentrate (NovoThirteen inj.) was licensed for prophylaxis in congenital FXIII-A subunit deficiency. The efficacy and safety of rFXIII in acute bleeding have not been tested. Aim : to report the effective use of rFXIII for the treatment of a major bleeding in a patient with severe inherited FXIII-A deficiency. Patient and methods : a 19-year-old man exhibiting severe bleeding phenotype without clear diagnosis was referred to our haemostasis centre. After presenting negative haemostasis screening tests he was evaluated for FXIII deficiency by the determination of FXIII activity, FXIII-A2B2, FXIII-A and FXIII-B concentrations and by mutation analysis. Results : severe FXIII-A deficiency was established and prophylaxis with rFXIII was planned. Prior to the start of the prophylaxis he was hospitalized due to a large intramuscular hematoma (19.0x8.3x7.7 cm) in the right thigh and rFXIII, in the prophylactic dose (35 IU/kg) was administered for therapy. Following the administration of rFXIII, the pain disappeared and the swelling of the thigh considerable decreased. Complete resolution of the hematoma occurred without any additional FXIII supplementation. Results of the pharmacokinetic assessment were comparable with those described in the literature. Conclusion : rFXIII can be successfully used in acute bleeding episode of severe congenital FXIII deficiency. Disclosures No relevant conflicts of interest to declare.