[Localized amyloidosis of the ureter and bladder treated effectively by occlusive dressing technique therapy using dimethyl sulfoxide: a case report].

We report here the first case of localized amyloidosis of the ureter and bladder to be treated effectively by occlusive dressing technique therapy using dimethyl sulfoxide. The patient was a 48-year-old woman whose chief complaint was macrohematuria and right back pain. Ultrasound sonography demonstrated right hydronephrosis and an intravesical mass in the region of the right ureteral orifice. Retrograde pyelography revealed severe stricture of the right lower ureter. Cystoscopy demonstrated a yellow submucosal tumor around the right ureteral orifice. We suspected urinary tract amyloidosis, and transurethral biopsy and resection of the intravesical mass were performed under right ureteral stenting. Histopathological diagnosis was amyloidosis. There was no evidence of systemic amyloidosis. To treat residual amyloidosis of the ureter and bladder, we performed occlusive dressing technique therapy using dimethyl sulfoxide every day. After 6 months of therapy, the right hydronephrosis disappeared, and there was no evidence of a recurrence of amyloidosis. We concluded that this therapy was very effective and safe for urinary tract amyloidosis.