Kikuchi-Fujimoto Disease

Kikuchi-Fujimoto disease, alternatively referred to as histiocytic necrotizing lymphadenitis or Kikuchi-Fujimoto disease, is a rare yet self-limiting inflammatory condition initially documented by Japanese pathologists Kikuchi and Fujimoto in Japan in 1972. Although the disease primarily affects young and pediatric patients of Asian descent, cases have been documented in individuals of diverse ages and ethnic backgrounds. The typical presentation is acute to subacute, characterized by painful, tender, mobile cervical lymphadenopathy associated with systemic symptoms, including fevers, malaise, weight loss, arthralgias, and various skin manifestations. An excisional lymph node biopsy is imperative for confirming a definitive diagnosis, revealing a deficiency of neutrophils and eosinophils. Immunohistochemistry will demonstrate histiocytes positive for myeloperoxidase and CD68, T cells positive for CD8, and a minimal presence of B cells. Fine-needle aspiration is typically inadequate for confirming the diagnosis due to the limited tissue sample acquired. Distinguishing Kikuchi-Fujimoto disease from lymphomas and infectious etiologies is critical, and additional support for the histologic diagnosis can be obtained through cultures and serological testing. Although the histology in systemic lupus erythematosus (SLE) lymphadenitis may bear a resemblance to Kikuchi-Fujimoto disease, the presence of hematoxylin bodies in SLE lymphadenitis aids in its distinction from Kikuchi-Fujimoto disease. SLE is the most prevalent autoimmune condition associated with Kikuchi-Fujimoto disease. However, unlike SLE, Kikuchi-Fujimoto disease typically follows a self-limiting course lasting several months, with a low recurrence rate of approximately 3% to 4%. The management of Kikuchi-Fujimoto disease primarily involves supportive care for patients, with the use of corticosteroids and immunosuppression reserved for cases of severe or recurrent disease. The prognosis is excellent, with rare complications such as hemophagocytic lymphohistiocytosis (HLH). Diagnostic challenges arise from the rarity of the disease, potentially leading to patients receiving inappropriate treatment for alternative etiologies. Therefore, raising awareness among clinicians and pathologists about this rare condition can significantly improve patient outcomes.