Kikuchi-Fujimoto's disease associated with systemic lupus erythematous: difficult case report and literature review.

Kikuchi-Fujimoto's disease (KFD), or histiocytic necrotizing lymphadenitis, is a benign and self-limiting disease of unknown aetiology. KFD tends to affect a young population under 30 years of age and predominantly females. KFD is a rare pathology and its association with systemic lupus erythematosus (SLE) is not frequent. Herein, we present the case of a male Italian patient with SLE in association with KFD with 5 years of follow-up, where a differential diagnosis from infection or lymphoproliferative disease was problematic.