Profile of Factor VIII Inhibitor Development in Adult Patients With Hemophilia A: An Observational Study in Surabaya, Indonesia

Abstract

Background: Inhibitor development was hemophilia treatment major complication. Inhibitor disturbed clinical response to replacement therapy affecting patient’s morbidity and quality of life. Its mechanism was multifactorial, that was patient-and therapy- related. Genetic and inhibitor test weren’t done routinely and they were high-priced. Hence risk factor identification was important to predict inhibitor development.

Aim: To know prevalence, socio-demographic and clinical characteristics and inhibitor FVIII development predictors in haemophilia A patients.

Method: This was a cross-sectional observational descriptive research in adult haemophilia A patients in Medical Oncology and Haematology dr. Soetomo General Teaching Hospital Surabaya and its satellite hospital from May until August 2023. FVIII inhibitor development predictors were disease degree, starting age of therapy, replacement therapy type and therapy intensity. FVIII inhibitor level was determined using Bethesda assay.

Result: Out of 30 subjects, inhibitor prevalence was 16,7%. Its median was 5,3 BU. The mean age was 31 years old and 97% of the subjects were male, 40%, 54% and 7% of the subjects were mild, moderate and severe haemophilia, respectively. FVIII inhibitor was detected in all severe haemophilia subjects, 25% subject was given first therapy when they were < 18 years old, 20% subject was given recombinant type and 24% subject had once a week injection.

Conclusion: FVIII inhibitor prevalence was 16,7%. Positive FVIII inhibitor was frequently found in severe haemophilia, starting age of therapy was < 18 years old, recombinant type therapy and had once a week injection.