Screening and quantitative estimation of factor VIII inhibitors by Nijmegen-Bethesda assay in hemophilia a patient of Southern Odisha, India

ABSTRACT

Background: The current treatment of haemophilia is replacement of factor VIII or IX which is effective till development of inhibitor against factors. There has been no study on factor VIII inhibitors in Southern Odisha using Nijmegen朆ethesda assay. This study was planned with objectives to screen factor VIII inhibitors in hemophilia-A patients, to do quantitative estimation of it using Nijmegen-Bethesda assay and to explore factors associated with development of inhibitors. Methods: This cross-sectional study was carried out from September 2016 to August 2018 in Department of pathology, MKCG medical college, Berhampur. Haemophilia-A patients coming to MKCG medical college and registered Haemophilia-A cases under Haemophilia society of Berhampur were included. Patients denying consent and having multiple clotting factors deficiencies were excluded. 1.8ml blood was collected. Mixing study was done to screen factor VIII inhibitors and then in positive cases inhibitors level measured by Nijmegen-Bethesda method. All data were analysed using SPSS (version 16.0).Results: 70 cases of Hemophilia-A patients were studied. Majority (50%) were with severe hemophilia-A. 7 patients developed inhibitors where 3 were high and 4 were low responders. Inhibitor level ranged from 0.8 to 64 Nijmegen-Bethesda units. Patients with severe hemophilia A, more than 10 transfusions and who switched to receive recombinant FVIII from other blood products developed inhibitors which were significant.Conclusions: Severity of hemophilia, increase frequency of transfusion and switching of blood products significantly increases chances of inhibitor development and hence intensive inhibitor screening is needed in these cases. Quantification of inhibitor is needed to monitor treatment and to manage bleeding episodes effectively.