Kikuchi–Fujimoto Disease Presenting With Complex Neurological Manifestations: A Case Report

Kikuchi–Fujimoto Disease (KFD) is a rare, typically self‐limiting inflammatory condition primarily associated with fever, cervical lymphadenopathy, and occasionally small‐vessel vasculitis. Central nervous system (CNS) involvement in KFD is exceedingly rare and has been described in isolated cases, including encephalitis, aseptic meningitis, and peripheral neuropathy. We described the case of a 43‐year‐old male of Indian descent who presented with a complex medical history of gait imbalance, falls, and slowness in daily activities, dysarthria, dysphagia, and excessive sleepiness, which had been progressively worsening over the past 16 months. His prior medical records included a diagnosis of Kikuchi disease in 2014, which manifested with fever and lymphadenopathy and resolved following steroid therapy. Subsequent evaluations ruled out other autoimmune and paraneoplastic conditions. Ultimately, a diagnosis of CNS involvement secondary to Kikuchi disease, possibly with vasculitis‐mediated pathology, was established. The patient was managed with rituximab, which significantly improved his symptoms. This case highlights the importance of considering rare and atypical neurological presentations of Kikuchi disease, along with the diagnostic challenges they pose. It is essential to conduct a thorough diagnostic workup that considers the full spectrum of disease presentations and tailors treatment to the specific underlying condition. Further, this case is an atypical and progressive presentation of KFD with extensive CNS involvement, emphasizing the role of vasculitis‐mediated pathology in such presentations and the effectiveness of rituximab in managing refractory cases.