A Case of Adverse Reaction to Booster Dose of COVID-19 Vaccination: Could D-Dimer Elevation Suggest Increased Clotting Risk?

Abstract

We report the clinical case of a 40-year-old Italian woman, who soon after her booster vaccination with mRNA-1273 after the two previous vaccinations with BNT162b2, developed severe headache, high fever, and Musculo-skeletal pain. She went to the emergency department, where computerized tomogra-phy (CT) scans of chest and brain were performed, resulting in both negative for pathologic findings. On the contrary, white blood count was strongly lowered and D-dimer severely elevated. She improved after treatment with enoxaparin and the blood analyses returned in the normal range after ten days. This case supports the hypothesis that COVID-19 vaccines could in-crease blood clotting in some predisposed subjects. Therefore, we believe that robust and well-designed clinical trials, considering the evaluation of D-dimer levels, should be performed to eliminate any doubts on this issue.