Development of Venous Thromboembolism After COVID-19 mRNA-1273 Vaccine Inoculation.

A 79-year-old man suddenly developed right lower extremity (RLE) pain and swelling a few days after receiving his 1st dose of the mRNA-1273 COVID-19 vaccine. Despite this, he proceeded to receive the 2nd dose of his mRNA-1273 COVID-19 vaccine. Investigations confirmed extensive acute deep venous thrombosis and a concurrent acute pulmonary embolism. Therapeutic anticoagulation was initiated and he was eventually discharged home on supplemental oxygen. The overall benefits of the vaccine in curbing severe disease overwhelmingly outweigh the handful of cases of reported adverse events. To our knowledge, this is one of the first few cases of provoked venous thrombosis after receiving the mRNA-1273 COVID-19 vaccine during the pharmacovigilance period.