Proliferative lupus nephritis in a patient with systemic lupus erythematosus and longstanding secondary amyloid nephropathy.

Secondary amyloidosis is an unusual complication of systemic lupus erythematosus (SLE). We report the case of a 60-year-old woman with SLE and secondary amyloidosis who developed class III proliferative lupus nephritis 13 years after the onset of amyloid nephropathy. The patient was treated with mycophenolate mofetil (1.5 g/day) with a significant improvement in proteinuria.