A 69-year old woman was diagnosed primary amyloidosis with renal involvement and nephrotic syndrome in 2006. She was treated by another nephrologist with 9 cycles of prednisone, melphalan and Rituximab. NS underwent partial remission, renal function remained normal. After the 9 cycles, she developed tubercular cystitis. She now has no evidence of active infective disease, but present a NS, normal renal function. What treatment options can be considered?