Vaccine-Induced Thrombocytopenia with Severe Headache

   This correspondence describes cases of vaccine-induced thrombocytopenia (VIT) with severe headache occurring 5 to 18 days post–ChAdOx1 nCoV-19 vaccination, suggesting a potential “pre-VITT syndrome.” Eleven patients had elevated D-dimer levels, thrombocytopenia, and high titers of anti–platelet factor 4 (PF4) IgG antibodies but lacked initial evidence of cerebral venous sinus thrombosis (CVST). Four patients later developed thromboses, with treatment delays correlating to progression. In contrast, early therapy including high-dose immune globulin and anticoagulation appeared to prevent CVST in others. The findings emphasize that headache may precede thrombosis and that early recognition and intervention could prevent progression to VITT. Immediate testing and tailored anticoagulation strategies are recommended in such cases.

   This correspondence describes cases of vaccine-induced thrombocytopenia (VIT) with severe headache occurring 5 to 18 days post–ChAdOx1 nCoV-19 vaccination, suggesting a potential “pre-VITT syndrome.” Eleven patients had elevated D-dimer levels, thrombocytopenia, and high titers of anti–platelet factor 4 (PF4) IgG antibodies but lacked initial evidence of cerebral venous sinus thrombosis (CVST). Four patients later developed thromboses, with treatment delays correlating to progression. In contrast, early therapy including high-dose immune globulin and anticoagulation appeared to prevent CVST in others. The findings emphasize that headache may precede thrombosis and that early recognition and intervention could prevent progression to VITT. Immediate testing and tailored anticoagulation strategies are recommended in such cases.