evaluation of inhibitor antibodies in haemophilia a population

background: inhibitory antibody to exogenous factor viii (fviii) is a major complication of hemophilia treatment. this study was conducted to determine the prevalence of inhibitor antibody directed against fviii.methods: from may 2010 to may 2011, 52 patients with severe hemophilia a admitted in amirkola children’s hospital were evaluated. those who had abnormal mixing study, antibody against fviii were measured. data were collected and analyzed. results: the age range of the patients was 4-60 years. the inhibitor antibody was seen in 9 (17.3%) patients. the mean age of patients with inhibitor at the time of diagnosis was 10.22 years (ranged 4-31 years). old patients had more hemarthrosis than young patients. the mean level of inhibitor antibody was 8.47 bethesda (ranged 2.3-29). six patients had inhibitor antibody level ?5 bethesda unit and three patients had inhibitor antibody level<5 bethesda unit.conclusion: this study showed that the prevalence of inhibitor antibody in young patients is more than the old patients.