Urethral stricture – Causes, Diagnosis, Treatment and Prevention

Definition

Urethral stricture is scar tissue with the urethra, which is the small tube that carries urine from the bladder to the outside. Normally the flow of urine through the urethra is free and easy, however when scar tissue forms it can cause a blockage that results in a slow urinary flow, or difficulty or inability to urinate. That blockage can occur anywhere from the bladder to the opening of the urethra into the vagina. Urethral strictures are relatively rare in women, but can be highly symptomatic. Fortunately, there are good treatment options.

A common cause of urethral stricture in boys is trauma from straddle injury.  Strictures can also be caused by pelvic fractures from major trauma.  Hypospadias repair is the most common surgery to cause urethral stricture disease, but prior instrumentation can also cause stricture disease.  Strictures can be prevented in people who intermittently catheterize by using liberal amounts of lubrication.

Stricture of the urethra in girls is rare and most often caused from prior surgery in that area or pelvic fractures from major trauma.  Please ask your physician about further details regarding urethral stricture in girls.

Urethra anatomy

Epidemiology

Urethral stricture is a relatively common disease in men with an associated prevalence of 229-627 per 100,000 males, or 0.6% of the at risk population, who are typically older men.

Types of Urethral stricture

Posterior Urethral Stricture

Posterior urethral strictures happen in the first 1″ to 2″ of the urethra. This kind of stricture is due to an injury linked to a pelvic fracture (e.g., motor vehicle or industrial accident). In these cases the urethra is disrupted, or completely cut and separated. Urine cannot pass. A catheter must be placed either through the abdomen into the bladder (suprapubic tube), or through the penis into the bladder. This lets urine drain until the stricture can be fixed.

Anterior Urethral Stricture

Anterior urethral strictures happen in last 9″ to 10″ of the urethra. This kind of stricture is caused by:

• Trauma from a straddle injury (from falls onto objects where the legs are on either side)
• Direct trauma to the penis
• Catheterization

Urethral stricture risk factors

A number of factors increase the risk of developing infections and injuries that can lead to scarring or inflammation of the urethra, resulting in urethral stricture. Risk factors include:

• Frequent bouts of urethritis (inflammation of the urethra)
• Male gender
• Multiple sexual partners, which increases the risk of having an STD
• Participation in sports without wearing protective gear over the genital area, which can result in a straddle injury. Examples include contact sports, baseball, or biking.
• Prolonged or extended urinary catheter use
• Scarring following genital piercing
• Surgery or instrumentation involving any structures of the lower urinary tract

Causes of Urethral stricture

Stricture or narrowing typically occurs due to chronic inflammation or the development of scar tissue at any point along the urethra. In many cases, the exact cause of scarring remains unknown, but there are a number of risk factors known to increase the risk of strictures including:

• Injury or trauma to external genitalia, perineum or pelvis.
• Damage from previous medical procedures such as prostate surgery or ureteroscopic kidney stone removal.
• Intermittent or long-term use of catheters.
• Sexually transmitted infections like gonorrhea and chlamydia.
• Prostate, penile and other urologic cancers.
• Radiation therapy.

Urethral stricture symptoms

Some cases of urethral stricture don’t exhibit any symptoms, while others can range from mild discomfort to complete urinary retention. Common symptoms of urethral stricture may include:

• Painful urination
• Urinary tract infection
• Slow urine stream
• Decreased urine output
• Spraying or dribbling of the urine stream
• Blood in the urine (“hematuria”)
• Abdominal pain
• Urethral discharge
• Urinary incontinence

Complications

Complications of stricture disease are:

• Urethral discharge
• Urinary tract infection
• Cystitis (inflammation of the bladder)
• Chronic prostatitis (inflammation of the prostate gland) or epididymitis (inflammation of the epididymis, a system of ducts that stores the sperm during maturation).
• Abscess in tissue surrounding the urethra
• Urethral diverticulum (abnormal pouch opening from the urethra)/calculus (hardened mineral salts)urethrocutaneous fistula (abnormal passage)
• Urethral cancer (one third to one half of males with urethral cancer have a history of stricture disease).
• Bladder stones (due to chronic slowing or stopping of urinary flow and infection).

Diagnosis and test

The diagnosis of urethral stricture begins with a history and physical exam. Patients will often describe certain risks factors (see above), and for those patients with the symptoms, described above, a thorough investigation is required to rule out urethral stricture or complications related to one.

Urinanalysis (U/A): Performed to rule out hematuria (blood in the urine), infection or other urinary abnormalities.

Urine culture: Studies the urine for evidence of infection, which may occur in some people with a urethral stricture.

Uroflowmetry/Peak flow urine study: Individuals are asked to void into a special toilet, which measures the speed at which urine flows from the bladder to the end of the urethra. Many individuals with a stricture will have a diminished rate of flow.

Post-void Residual Urine Study: an ultrasound of the bladder is performed, measuring the amount of urine that remains after a “normal” void (urination).

Retrograde Urethrogram (RUG) with Voiding Cystourethrogram (VCUG): X-ray constrast (dye) is used to fill the urethra and bladder as images are obtained, identifying the level of blockage. Men are then asked to void (VCUG) and again x-rays are taken to better outline the level of stricture.

Cystoscopy: using a fiberoptic telescope the urinary tract from the tip of the penis to the bladder can be inspected. This can help rule-out other causes of obstruction or allow the urologist to better characterize the stricture.

Sonourethrogram: This test is usually done in the operating room as part of the pre-operative surgical planning. It involves an ultrasound probe to image the stricture, measure stricture length and assess the degree of urethral scarring.

Most patients will have a urinalysis, urine culture, uroflowmetry, post-void residual study and a RUG/VCUG. Cystoscopy may not be required and its need will be determined by the doctor.

An X-ray obtained in a patient with a normal urethra.

Treatment and medications

There are several treatment options for relieving a urethral stricture:

Temporary and permanent catheterizations: Catheters are thin tubes inserted in the urethra and bladder, with the purpose of relieving urinary retention through the drainage of unpassed fluids. In more severe cases, a permanent catheter or stent can be used to maintain urine flow indefinitely, though procedures of this type come with increased risks of bladder irritation and urinary tract infections.

Dilation: Dilation is an outpatient procedure in which a series of increasingly large dilators are inserted into the urethra by means of a wire. These dilators gradually expand the urethral passage, making possible a greater flow of urine from the bladder.

Surgical repair

Cystoscopy: During surgery the urologist will insert an instrument into the urethra, called a cystoscope. A cystoscope is a small device with a light and a camera lens at the end. This provides direct visualization of the urethra and possible stricture.

Endoscopic urethrotomy: This procedure involves the cystoscope, which is inserted in the urethra with an instrument package for eliminating obstructive material. One of the available instruments is a tiny laser for vaporizing scar tissue.

Urethroplasty: Urethroplasty is a surgical procedure for removing a constricted portion of the urethra and then rejoining the two healthy segments. An alternative treatment involves reconstructing a portion of the urethra using organic tissues from another location in your body.

Preventing urethral strictures comes to down avoiding the injuries and infections which are the primary causes of it. In other words, take common sense precautions.

The good news about urethral strictures is that, if you develop one, medical treatments have proven reasonably effective in their control. Recurrence is fairly common, however.

Prevention of Urethral stricture

Preventing a urethral stricture is not always possible. However, there are some steps a person can take to reduce the chance that they will develop one.

The following are some ways to help prevent urethral strictures:

• If a person must self-catheterize (insert a catheter themselves to eliminate urine), use lubricating jelly and the smallest possible catheter for the shortest time frame possible.
• Use barrier protection during sexual activity to help prevent the transmission of chlamydia or gonorrhea.
• Avoid having sexual intercourse with partners who have an infection.
• Get tested regularly for STIs, including gonorrhea and chlamydia, and seek the appropriate treatment.

Taking steps to prevent pelvic injuries, such as wearing appropriate protective equipment when playing sports, can also help prevent urethral strictures.