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Updated: May 14, 2026

Urethral Stricture Induction Followed by Buccal Mucosa Graft Urethroplasty in a Rat Model
Published on: April 28, 2023
[Amyloidosis of the urethra: a case report]
Ryuta Watanabe1, Takashi Uda, Kouji Inada
1The Department of Urology, Uwajima City Hospital.
Abstract:
A 26-year-old man was introduced to our hospital with a complaint of macrohematuria. Endoscopic examination showed a small tumor in the anterior urethra. Microscopic examination of a biopsy specimen taken under lumbar anesthesia showed amyloid deposition in the urethral submucosa. On Congo red staining, amyloid was visualized as orange material, showing characteristic birefringence under polarized light. Amyloidosis of the urethra was diagnosed. Because the patient refused to undergo duodenal or rectal biopsy, the possibility of systemic amyloidosis could not be completely excluded. No recurrence has been noted since the endoscopic examination, and no further symptoms have been reported.
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