RESUMEN
Factor VIII inhibitor is one of the most problems in the treatment of hemophilia. Patients with hemophilia who have inhibitors are capable of severe hemorrhage and treatments of these patients are more expensive and more difficult than those patients without inhibitor. The aim of present study was to determine the prevalence of inhibitor and to assess the necessity of screening of the factor VIII inhibitors in hemophilia patients. 104 patients with hemophilia A referred to Besat Hospital of Sanandaj during 2006-2009 were evaluated for inhibitors against factor VIII using convenient sampling method. Their venous blood samples were mixed in a proportion of 9 to 1 with 3.2g/dl citrate sodium. After preparation of plasma APTT mix test and then Bethesda test followed by determination of inhibitor were performed. The mean age of subjects was 23.8-+/9.3 year. Twenty out of 104 patients with hemophilia A [19.2%] had inhibitor factor VIII. None of patients were assayed for inhibitor previously. Sixteen patients were low responder and four patients showed high responder with the Bethesda inhibitor level above five unit. Higher levels of inhibitor were existed in 11-25 years old age groups. There was no significant relationship between factor VIII inhibitor and patient's age. Regarding to high prevalence of the factor VIII inhibitor in these patients, screening all hemophilia A patients every 6 months and doing Bethesda test for new identified cases with this inhibitor is highly recommended