학술논문

The factor VIII:C/VWF:Ag ratio as a useful tool to predict relapse in patients with acquired haemophilia A: A retrospective cohort study.
Document Type
Article
Source
Haemophilia. May2019, Vol. 25 Issue 3, p527-534. 8p. 1 Diagram, 2 Charts, 3 Graphs.
Subject
*PARTIAL thromboplastin time
*BLOOD coagulation factors
*COHORT analysis
Language
ISSN
1351-8216
Abstract
Introduction: Acquired haemophilia A (AHA) is a rare autoimmune bleeding disorder caused by the presence of autoantibodies against coagulation factor VIII (FVIII). The mortality rate remains high. International recommendations define complete remission as undetectable inhibitor (<0.6 Bethesda Units [BU]) and normal FVIII activity (FVIII:C) that persists after immunosuppressive therapy stopped. For patients achieving remission, the risk of relapse reaches 20%. The risk factors for this relapse are not well known. Aim: In this study, we examined the accuracy of the FVIII/W ratio (FVIII:C/von Willebrand Factor Antigen (VWF:Ag) ratio) to predict relapse in 64 consecutive patients with AHA. Results: In this cohort, all patients had a very low FVIII/W ratio at the time of diagnosis, and this value progressively increased in the first weeks of immunosuppressive treatment. In our study, 9/55 (14%) did not achieve complete remission. Twenty‐seven patients were followed long enough (more than a year) to show that in the 22 patients who did not relapse, the FVIII/W ratio remained durably normalized. By contrast, in the five patients who relapsed during follow‐up, we noted either no normalization of the FVIII/W ratio, or a secondary decrease to an abnormal value of <0.7 after initial normalization. In all patients who relapsed, the ratio was the first abnormal biological result to be observed, always preceding changes in the activated partial thromboplastin time (aPTT), FVIII:C and anti‐FVIII reappearance. Conclusion: These data suggest that the FVIII/W ratio could be considered a sensitive biological marker to predict recovery and/or relapse in AHA. [ABSTRACT FROM AUTHOR]