Kikuchi-Fujimoto disease following vaccination against COVID-19.

The purpose of this study is to explore the clinicopathological features of Kikuchi-Fujimoto disease (KFD) following vaccination against coronavirus disease 2019 (COVID-19). One case of KFD following vaccination against COVID-19 was examined clinically, histologically, and immunohistochemically. The patient was a 36-year-old Chinese man who suffered from fever and cervical lymph node swelling following simultaneous administration of the COVID-19 vaccine. The patient was diagnosed with KFD based on the histopathological findings of a lymph node core needle biopsy, and his fever and swelling resolved 2 months later without therapy. Although the exact pathogenesis of the development of KFD following immunization remains unknown, this information should be added to the list of potential triggers or factors associated with the development of KFD.