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Urethral stricture: etiology, investigation and treatments.

BACKGROUND
Urethral stricture is a narrowing of the urethra due to scar tissue, which leads to obstructive voiding dysfunction with potentially serious consequences for the entire urinary tract. Its prevalence among men in industrial countries is estimated at 0.9%. It produces obstructive and irritative urinary symptoms and can ultimately impair renal function. Urethral strictures can be caused by diagnostic or therapeutic urological procedures. These procedures are being performed ever more commonly, because the population is aging; thus, urethral strictures will probably become more common as well.


METHODS
We selectively reviewed pertinent original articles and meta-analyses (1995-2012) on the causes, diagnostic evaluation, and treatment of urethral strictures, which were retrieved by a search in the PubMed database.


RESULTS
Most of the relevant publications are reports of retrospective studies from single centers. Only a few prospective randomized trials and structured reviews are available. The overall level of the scientific evidence is low. 45% of urethral strictures are iatrogenic, 30% idiopathic, and 20% due to bacterial urethritis. Strictures are diagnosed with a flow test and a retrograde urethrogram. Short bulbar strictures can be treated endoscopically. For recurrent and complex strictures, only open urethral surgery can reliably and permanently remove the infravesical obstruction.


CONCLUSION
Urethral strictures must be recognized and treated so that their most serious long-term complication, impaired renal function, can be prevented. The clinical utility of urethrotomy is limited by a high recurrence rate.