A retrospective study at Tongji Hospital in Wuhan, China, evaluated 15 patients with fever of unknown origin who were diagnosed with histiocytic necrotizing lymphadenitis. All presented with fever and cervical lymphadenopathy, with frequent leukopenia and elevated inflammatory markers. Positron emission tomography/computed tomography revealed hypermetabolic lymph nodes in most patients but suggested lymphoma or other diseases in 73%, leading to potential misclassification. Biopsy confirmed the diagnosis, showing disrupted nodal architecture and absence of neutrophils. All patients improved with corticosteroid therapy, and three received intravenous immunoglobulin. During at least three years of follow-up, one patient experienced recurrence and one developed systemic lupus erythematosus. The researchers noted the importance of biopsy in distinguishing this condition from lymphoma and reported that the small sample size limited generalizability.

Source: Diagnostic Pathology