A case of Kikuchi-Fujimoto disease with autoimmune thyroiditis.

Kikuchi-Fujimoto disease (KFD) is a benign self-limiting disease characterized by fever and lymphadenitis. The etiology and pathogenesis of KFD is unclear. However, two hypotheses have been suggested: a viral infection hypothesis and an autoimmune hypothesis. Several KFD patients with various types of autoimmune diseases have been reported, and these reports support the hypothesis for autoimmune pathogenesis of KFD. Here, we report the case of a 17-year-old female patient diagnosed with KFD and autoimmune thyroiditis. This case serves as additional evidence that the etiology of KFD is autoimmune origin.