Heparin-induced thrombocytopenia (HIT) and vaccine-induced immune thrombotic thrombocytopenia (VITT) are anti-platelet factor 4 (PF4) disorders caused by platelet-activating antibodies acting against PF4. Adenoviral vector COVID-19 vaccines have been reported to cause VITT. However, an association between adenovirus infection and anti-PF4 disorders has not yet been reported. Recently, while treating a 58-year-old woman and a 5-year-old boy with adenovirus infection, severe thrombocytopenia, and thrombotic events, clinicians found an association between the adenovirus infection and anti-PF4 disorders.
VITT-like antibodies against PF4 were found in the serum samples of these patients. The antibodies were also found to be against only PF4, ruling out the involvement of heparin-dependent antibodies, which recognize both PF4 and heparin. This is the first report showing an association…
