[A young woman with rheumatoid arthritis who rapidly developed secondary amyloidosis]

A 22-year-old woman, who had been diagnosed as having rheumatoid arthritis (RA) 2 years before, was admitted to our hospital complaining of watery diarrhea (several times/day). She had been treated with low dose prednisolone (PSL) and auranofin in out-patient clinic. On admission, laboratory data showed moderate proteinuria (0.3 g/day) and positive CRP (2.7 mg/dl). Although the activity of RA was controlled by the administration of low dose methotrexate (7.5 mg/week) in addition to PSL, watery diarrhea and proteinuria did not improve. The biopsy of the stomach, rectum and kidney revealed the deposition of AA type amyloid protein, resulting in the diagnosis of secondary amyloidosis. Secondary amyloidosis has been reported as one of the common complications in RA patients, especially in old patients with a long history of RA. To our knowledge, however, there have been few reported cases who developed secondary amyloidosis so early during the course of RA as our case. We should be careful for the development of secondary amyloidosis even in young RA patients with short history of RA, when the disease is active.