Saturday, May 8, 2010

stricture urethra: a review

Urethral stricture is an abnormal narrowing of the urethra (the tube that releases urine from the body).



Causes, incidence, and risk factors
The most common cause of anterior urethral stricture is infections.Sexually transmitted diseases can cause infection of the urethral glands(for ex.Bulbo-urethral glands) and resultant inflammation and fibrosis of the region
Other common causes are Balanitis Xerotica Obliterans/lichen sclerosis which can lead to stricture of the whole urethra(pan urethral stricture).This disease usually involves the glans,meatus and the penile pendular urethra.Usually shrunken atrophic glans with meatal narrowing with whitish patches are found on the glans The involvement due to Lichen Sclerosis can be more proximal on the penile skin and pendulous urethra, which is more common than previously thought. Although penile skin may appear normal, microscopic involvement may be present. Moreover it is known that endoscopic manipulation of meatus involved with Lichen Sclerosis also has a potential of disseminating the disease into proximal urethra causing pan-urethral stricture
The trauma either direct because saddle injury or pelvic trauma incurred during the road traffic accidents can cause anterior and posterior urethral injuries and stricture respectively.
The instrumentation (traumatic or repeated) can also lead to trauma. The carcinoma bladder patients who undergo repeated intervention are more prone. Also prostatic enlargement patients who undergo endoscopic prostatectomies are also prone for stricture especially if the gland size is big because the dwelling time of the instruments inside body will be higher in such cases.This will also make urethra more prone for instrumentation leading to stricture.


Symptoms




1)dysuria, weak interrupted stream,urgency,urge incontinence,frequency
2)Recurrent Urinary Tract Infections
3)Hematuria
4)Retention of the urine
5)Urinary incontinence
6)Renal function deterioration



Signs and Tests
A physical examination may reveal the following:
1) Hardness (induration) on the under surface of the penis
2) Whitish Patches on glans,meatal narrowing,shrinkage and atrophy of the glans indicative of Balanitis Xerotica Obliterans
3) Sometimes urethrocutaneous fistula can be found
4) Evidence of pelvic fracture/scars of previous Supra Pubic Catheter placement can also be found.

Sometimes the exam reveals no abnormalities:
Tests include the following:
1) Urinary flow rate
2) Post-void residual (PVR) measurement
3) Urinalysis /Urine culture
4) Tests for chlamydia and gonorrhea
5) A retrograde urethrogram to confirm diagnosis



6) Urethroscopy

Treatment
Placement of a suprapubic catheter , which allows the bladder to drain through the abdomen, may be necessary to alleviate acute problems such as urinary retention and infection especially after trauma .

Surgical options vary depending on the location and length of the stricture.

Visual internal urethrotomy may be all that is needed for small stricture. A urethral catheter is left in place after the procedure for anywhere from 3 -10 days .This duration varies from surgeon to surgeon But everybody would agree on principle that prolonged catheterization doesnot prevent the chance of urethral stricture recurrence

An open urethroplasty may be performed for longer stricture by removing the diseased portion or replacing it with other tissue. The results vary depending on the size and location of stricture, the number of prior therapies, and the experience of the surgeon.



Buccal Mucosal Graft Interposition in one case of anterior urethral stricture

In some patients of failed urethroplasties or where the patient is not a good candidate for surgery or even in primary cases stenting is a worthwhile option.The stent is made up of Nickel Titanium Alloy (Memokath 044) and has only a few side effects.The stent is inserted in urethra with the telescope and then expanded with the warm saline irrigation.It expand from 24 to 44 CH.The stent is available from 3 to 7 cms in length.This stent equally easy to remove.















Photograph of the urethral stent placed in long segment urethral stricture



There are no drug treatments currently available for this disease. If all else fails, a urinary diversion -- appendicovesicostomy (Mitrofanoff procedure) -- may be performed to allow the patient to perform self-catheterization of the bladder through the abdominal wall.

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