[Renal amyloidosis complicating adult onset Still's disease: about three cases]

Renal amyloidosis is a rare complication of adult onset Still's disease. We here report three cases of renal amyloidosis in a series of 33 cases of adult onset Still's disease. The three patients enrolled had an average age of 43 years (with a range from 33 to 58 years). The diagnosis of Still's disease was retained on the basis of febrile polyarthritis (3 cases) associated with fleeting rush (1 case), biologic inflammatory syndrome in the absence of any infectious, inflammatory or neoplastic causes. All patients were treated with corticosteroids secondarily associated with methotrexate due to destructive polyarthritis (2 cases) and to a recurrence (1 case). Renal amyloidosis had occurred 4.9 years after Still's disease (with a range from 33 months to 7 years). Amyloidosis was revealed by nephrotic syndrome (3 cases) associated with renal failure (1 case). Diagnosis was based on renal puncture biopsy (3 cases) which showed AA amyloidosis (2 cases) and untyped amyloidosis (1 case). All patients received colchicine. Outcome was favorable in a female patient while in the other two patients the disease progressed to chronic renal failure. Renal amyloidosis uncommonly results from adult onset Still's disease. Once the disease gets established it can be life-threatening.