Case report: Interleukin‐6 positive follicular hyperplasia in the lymph node of a patient with rheumatoid arthritis

We examined interleukin‐6 production in the hyperplastic lymph node of a 77‐year‐old male rheumatoid arthritis patient with lymphadenopathy. The interleukin‐6 production of the lymph node was observed by both immunohistological staining and in vitro culture. The results suggest that interleukin‐6 plays a significant pathogenic role in the etiology of the lymphadenopathy seen in many rheumatoid arthritis patients.