Acquired hemophilia A following SARS CoV-2 mRNA vaccine: Correspondence

Abstract

We would like to comment on the publication "Acquired Hemophilia A (AHA) following Pfizer-BioNTech SARS CoV-2 mRNA vaccine, successfully treated with prednisolone and rituximab." 1 Murali et al. 1 noted that in patients who have bleeding after receiving COVID-19 vaccine but have a normal platelet count, AHA should be considered. To reduce morbidity and death, Murali et al. 1 suggested for early detection, immediate commencement of immunosuppressive medication, and strict supportive care are essential. We agree that COVID-19 immunization may cause hematologic complications.This clinical issue has been reported in infrequent cases. [2][3][4] In the case report by Murali et al., 1 the patient had hemorrhagic problem but the cause is still not conclusive. Murali et al. 1 described a case and offered etiology theories. The immunopathological process was mentioned as a possible underlying mechanism. The actual pathomechanism, however, is unknown. Although aberrant immunity may be considered, there is little information on the immunological status of the cases before vaccination, making it impossible to rule out a pre-existing clinical condition. In the present report, it is not possible to exclude the pre-vaccination hematological problem. AHA might be chronically silent, asymptomatic, and self-limiting. 5,6 Finally, we would want to emphasize the significance of recognizing this issue. The condition could be mistaken as another endemic clinical problem, such as dengue fever, in some contexts. 7