Abstract
During the coronavirus disease 2019 (COVID-19) pandemic, mass vaccination was a beneficial strategy in many countries. Nevertheless, reports of serious complications such as postvaccination neuromyelitis optica spectrum disorder (NMOSD) raised concerns about the safety of vaccines. Anamnart and colleagues explained postvaccination NMOSD following different vaccines, including COVID-19. To emphasize the message of this article, in this letter, we present a unique case of postvaccination NMOSD with a fulminant and fatal course, which may show a plausible relationship between COVID-19 vaccination and triggering anti-aquaporin-4 antibody (AQP4-Ab).