LAUSR

Abstract Background Histological evaluation of lymph node is crucial for the definitive diagnosis of Kikuchi–Fujimoto disease (KFD). However, lymph node biopsy under local anesthesia is often difficult in pediatric patients. Objectives We evaluated cytological findings for pediatric patients with prolonged cervical lymphadenitis clinically suggestive of KFD and investigated the clinical characteristics of patients diagnosed with KFD by fine-needle aspiration cytology (FNAC). Methods This retrospective clinical study included 58 Japanese pediatric patients with cervical lymphadenitis who underwent FNAC. Results Cytological diagnosis was KFD for 22 and suspicion of KFD for 11 patients. The remaining 25 patients were diagnosed with non-specific lymphadenitis (NSL). Tenderness was independently associated with a higher frequency of both KFD in narrow and broad senses, compared with NSL (p = .009; p = .038). The percentage of patients who underwent FNAC within 28 days from symptom onset tended to be higher among patients with KFD in a narrow sense than those with NSL (p = .052). Conclusion This study indicated that the period from symptom onset to FNAC (<28 days) and the symptom of tenderness were associated with the cytological diagnosis of KFD.