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Updated: Feb 11, 2026

Urinary Bladder Distention Evoked Visceromotor Responses as a Model for Bladder Pain in Mice
Published on: April 27, 2014
Unusual case of simple urinary bladder melanosis with complete resolution
Zaid Mera1,2, Sheena Patel1, Omar Qassid3
1Department of Urology, Kettering General Hospital NHS Foundation Trust, Kettering, UK.
Abstract:
A 66-year-old man presented with a long history of recurrent attacks of urinary retention and lower urinary tract symptoms. Flexible cystoscopy showed a urethral stricture. Follow-up cystoscopy 7 years later for recurrent symptoms demonstrated unusual extensive mucosal brown to black pigmentation, which proved histopathologically to be a simple bladder melanosis. Follow-up demonstrated complete resolution over a period of 1 year with no specific treatment. In this report, we highlighted a rare bladder abnormality with uncertain natural history.
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