Background and Objectives: Hemophilias are the most common inherited coagulation factor deficiencies. Factor VIII deficiency accounts for 80% cases of Hemophilia. The treatment modalities available have drastically changed the lives of PWH in the last five decades. With the advent of factor replacement therapy, PWH experience the complications in the form of development of inhibitors to Factor VIII. The objective was to study the prevalence of these inhibitors using Bethesda assay.

Methods: This was a cross sectional study done among forty PWH at St. Johns Medical College Hospital. A follow up study was done in 47 percent of the low responders.

Results and Conclusion: Mean age of the PWH was 26.15 years.60 percent of the study population was diagnosed before 10 months of age and 90 percent were less than 40 years of age. Among the PWH studied 70 percent had severe hemophilia. The study included only the persons with congenital hemophilia and hence 100 percent were males. All PWH had mixed exposures to factor viii and blood products. The Bethesda assay was positive for 67.5 percent of the persons with hemophilia. Low responders were 42.5 percent and high responders were 25 percent. Among the low responders a repeat Bethesda was done on 47.05 percent PWH after a gap of one year to study the nature of inhibitors.37.5 percent of PWH in whom a repeat Bethesda was done turned negative and 62.5 percent remained positive

There was a significant positive relation between age of the PWH at the time of study and age at the time of diagnosis with the level of factor VIII. PWH with older age at the time of study and at the time of diagnosis had better level of factor viii. We found that subjects in the study group were diagnosed at a younger age. Young age at the time of diagnosis was associated with worse pain and bleeding scores. PWH with a severe disease had worse bleeding and pain scores. PWH with multiple exposures to factor VIII and blood products had worse bleeding and pain scores.

There was a negative relation between level of inhibitor and age of diagnosis and level of factor VIII but it was not statistically significant. A statistically significant correlation was found between the level of inhibitor and exposure to factor VIII but none of the PWH were exposed to factor VIII alone,  the exposure was mixed including blood products. There was no statistically significant correlation between Bethesda score and total number of exposures. Most PWH had a bleeding and pain score of 2 which was not different in PWH with and without inhibitor. Similarly there was no significant difference in QOL in persons with or without inhibitors.

Keywords: Hemophilia, PWH, Bethesda assay, Factor viii, FEIBA, ITC, QOL, Pain score, bleeding score

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Dr Chaitanya H. Balakrishnan

St. John's Medical College Hospital, Bangalore

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