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    Poster Networking

    Hemophilia and Rare Bleeding Disorders

    Poster Networking Session

    PB1225 - Acquired haemophilia in the COVID-19 pandemic era – does vaccination or infection increase its risk and influence outcomes?

    Tuesday, June 27, 2023
    18:30 – 19:30 ET
    Room: Exhibition
    Background: Acquired haemophilia A (AHA) is a rare bleeding disorder which is associated with conditions such as autoimmunity, malignancy and infections. Recent reports have anecdotally cited the COVID-19 infection or vaccinations as possible precipitants.

    Aims: To investigate the pre-pandemic and pandemic incidence and outcomes of AHA in the main tertiary haematology centre in Singapore to determine possible associations with infection/vaccination.

    Methods: AHA cases diagnosed between 2015 to 2022 were collated to compare pre and post-COVID-19 pandemic incidence. Treatment outcomes among patients in 2022 were compared against a historical cohort in our centre.

    Results: The first case of COVID-19 infection was detected in January 2020. Since then, Singapore has experienced 5 waves of infections with 2.2 million cases among its resident population of 5.9 million. A nationwide vaccination program was started in early 2021 with 92% of the population vaccinated since 2022. The incidence of AHA in our centre, which serves 60% of the population is shown in table 1. There was no significant difference in the estimated population incidence of AHA before and after the pandemic.

    Among the 8 cases diagnosed in 2022, 7 were fully vaccinated (88%) consistent with the nation’s vaccination coverage. 1 patient had COVID-19 diagnosed within a month of diagnosis. Close to 2 million COVID-19 cases were diagnosed in 2022 alone. Among the 6 evaluable cases treated in 2022, 4 achieved a complete remission (66%) with treatment ongoing for the other 2. Our published historical cohort using the same treatment regimen achieved a complete remission rate of 88%.

    Conclusion(s): COVID-19 infections and vaccinations do not appear to increase the incidence nor influence the treatment outcomes of AHA. As we enter the endemic era of COVID-19, further validation of this information will provide assurance to the safety of vaccines as well as the effects of infection.