Kikuchi Fujimoto Lymphadenitis: A Rare Association With COVID-19 Vaccination

Kikuchi-Fujimoto disease (KFD), also known as histiocytic necrotizing lymphadenitis, is an uncommon cause of protracted cervical lymphadenopathy in both children and adults. Although the majority of cases have been documented in Asia, this disease has been characterized globally since it was first identified in Japan in 1972. KFD's etiology is not entirely understood, although various theories have been postulated. Usually benign, Kikuchi-Fujimoto disease resolves within six months. KFD must be distinguished from other causes of chronic lymphadenopathy, such as lymphoma, inflammatory illnesses, autoimmune conditions, viral lymphadenopathy, and also from tuberculosis, especially in India, where it is still endemic. Here, we present the case report of a healthcare worker with a known case of hypothyroidism and autoimmune skin disorder who presented with prolonged fever, joint pain, and generalized lymphadenopathy post-COVID vaccination and was diagnosed as having KFD on biopsy, which can be associated with a very unusual presentation of this disease.