We report herein the pathological findings and clinical courses of two cases of Kikuchi-Fujimoto disease (KFD) that developed into autoimmune diseases. The patients are currently undergoing treatment for a disease similar to Sjogren's syndrome and systemic lupus erythematosus/mixed connective tissue disease. KFD is not an independent condition and most likely develops due to an autoimmune mechanism. Pediatricians should pay careful attention to KFD and encourage long-term follow-up in patients with this condition.
