Diagnostic Challenges and Scientific Management of Suspected Recurrent Kikuchi-Fujimoto Disease: A Case Report.

BACKGROUND Kikuchi-Fujimoto disease is a rare, benign, and self-limiting disease typically characterized by persistent fever and lymphadenopathy. The clinical manifestations are nonspecific, and consensus diagnostic criteria are currently unavailable; therefore, it is easily misdiagnosed as lymphoma, tuberculosis, or autoimmune diseases. Definite diagnoses rely on lymph node biopsy results. Recurrence of Kikuchi-Fujimoto disease is not uncommon, with recurrence rates varying across different age groups, ranging from 3% to 42.4%. Most patients have a favorable prognosis, while some progress to autoimmune diseases during follow-up. CASE REPORT A 26-year-old man presented with a history of recurrent fever with lymphadenopathy and positive autoantibodies. He received empirical treatment for an upper respiratory tract infection in the early stage; finally, Kikuchi-Fujimoto disease was confirmed by lymph node biopsy. Given the patient's similar clinical symptoms without prior pathological confirmation 2 years ago, we presumed that the current episode was a recurrence of Kikuchi-Fujimoto disease. CONCLUSIONS The case exemplifies the diagnostic challenges of Kikuchi-Fujimoto disease. It is easily neglected by clinicians due to insufficient awareness of the disease, and Kikuchi-Fujimoto disease should be included in the differential diagnosis of fever of unknown origin. Choosing appropriate diagnostic modalities is crucial for establishing a timely and definitive diagnosis. Although the recurrence in this case was presumed, recurrence does occur with a certain incidence in Kikuchi-Fujimoto disease; therefore, long-term follow-up observation is necessary for Kikuchi-Fujimoto disease, especially for patients with positive autoantibodies.