Kikuchi-Fujimoto Disease Presenting as Necrotic Cervical Lymphadenopathy Mimicking Tuberculous Lymphadenitis in a Young Woman With Strong Familial Autoimmunity: A Case Report

Kikuchi-Fujimoto disease (KFD), also known as histiocytic necrotizing lymphadenitis, is a rare and usually self-limiting condition that predominantly affects young adults, particularly women.It commonly presents with fever and cervical lymphadenopathy and may be accompanied by weight loss, night sweats, and fatigue.Due to its nonspecific presentation, KFD can mimic infectious, malignant, and autoimmune conditions, making diagnosis challenging.We report the case of a 20-year-old woman with a significant family history of autoimmune disease who presented with a two-week history of intermittent fever, progressively painful left-sided cervical lymphadenopathy, weight loss, night sweats, and lethargy.Initial investigations revealed leukopenia and raised inflammatory markers, while computed tomography demonstrated bilateral cervical lymphadenopathy with a necrotic left cervical lymph node.Lymph node biopsy demonstrated necrotising lymphadenitis consistent with KFD.Subsequent investigations revealed positive anti-double-stranded DNA antibodies, negative antinuclear antibodies, and lupus-like clinical manifestations, raising the possibility of an evolving autoimmune disorder.This case highlights the importance of considering KFD in the differential diagnosis of young patients presenting with fever and cervical lymphadenopathy, particularly when autoimmune features and a significant family history are present.It also emphasises the importance of distinguishing KFD from lupus lymphadenitis and the need for ongoing rheumatological surveillance.