[Malignant lymphoma with gastrointestinal amyloidosis, developing in the course of rheumatoid arthritis]

A autoimmune diseases complicated by malignant lymphoma have attention recently. studies in the international literature have demonstrated a significant complication of rheumatoid arthritis (RA) with malignant lymphoma. The authors report a case with a 15-year history of RA complicated with B cell lymphoma and gastrointestinal amyloidosis. A 66-year-old-woman was presented with easy fatigability and weight loss. with fever above 38 degrees C (100 degrees F). Clinical examination revealed marked abdominal tenderness and deformed joints of both hands and fingers. Rheumatoid factor was weakly positive. A diagnosis of malignant lymphoma (follicular large, B cell type) was made by inguinal lymph node biopsy and endoscopic biopsy which revealed amyloid (AA type) deposition in the stomach and duodenum. The case showed a remarkable increase of a specific antibody titer against Epstein-Barr (ER) virus, which has been suggested to cause RA or lymphoma. The complications of the diseases in this case suggests a similar causative mechanism for the two different diseases.