Wild-type ATTR amyloidosis of the ureter in a 56-year-old woman with rheumatoid arthritis and Sjögren's syndrome.

We present a case of acute pyelonephritis with right hydronephrosis in a middle-aged woman, who had suffered from rheumatoid arthritis and Sjögren's syndrome. She had successfully treated with antibiotics, however, ureteral stenosis sustained. She underwent ureteroscopy and stenting of right ureter. Biopsy specimen revealed submucosal amyloid deposition in the interstitium overlying a benign urothelium. Amyloid protein was positive for transthyretin (TTR) by immunohistochemistry and amyloid deposition was not demonstrated in other organs. The patient's TTR genes were wild type and she was diagnosed with wild-type ATTR (ATTR wt) amyloidosis. This is the first report about symptomatic ATTR wt amyloidosis, which was also called 'systemic senile amyloidosis (SSA)' in the ureter. We should aware that SSA can occur at younger age and cause symptomatic ureteral stenosis. Further investigation is needed to clarify the association of autoimmune diseases to develop ATTR wt amyloidosis.