SARS-CoV-2 vaccination associated venous sinus thrombosis in three patients.

Introduction: There is increasing evidence that vaccinations against the severe acquired respiratory syndrome coronavirus type-2 (SARS-CoV-2) virus can be followed by venous sinus thrombosis (VST). Here we report on three patients who developed VST shortly after SARS-CoV-2 vaccinations.

Case series: An 80-year-old male, a 58-year-old male, and a 34-year-old female developed VST 14 to 24 days after the first dose of an mRNA-based SARS-CoV-2 vaccine. All three patients profited from analgesics, heparinisation, and oral anticoagulation, but made only an incomplete recovery at the time of discharge. Arguments for a causal relationship are: VST was time-linked to vaccination in the three patients; VST was previously reported after SARS-CoV-2 vaccination; SARS-CoV-2 infections can be complicated by VST; and SARS-CoV-2 can be associated with hypercoagulability. The fact that no hypercoagulability occurred in a pilot study after SARS-CoV-2 vaccination and that there has been no evidence of an increased prevalence/incidence of VST after vaccination since the introduction of the SARS-CoV-2 vaccination speak against a causal relationship.

Conclusions: SARS-CoV-2 vaccinations can occasionally be followed by a VST. There are more arguments for than against a causal relationship.