The narrowing of the urethra (urethral stricture) is usually based on a scarring change in the urethra. Mainly men are affected. The narrowing of the urethra is usually noticeable through a changed urinary stream or more frequent urinary tract infections. There are a variety of surgical treatment options for a urethral stricture. Read more about the therapy, the symptoms and the diagnosis of urethral stricture here!
ICD codes for this disease: N35
- Treatment: expansion or surgery (urethral slit, reconstruction, less common stent)
- Symptoms: Altered, weakened urinary stream, frequent urge to urinate, urinary retention, interruption in urination, incontinence, possibly blood in the urine
- Causes: mostly unclear, injuries during operations, accidents, inflammation of the urethra ; rarely congenital or due to an inflammatory skin disease or mechanical influences
- Examinations and diagnosis: Physical examination, urine examination, measurement of urine flow, ultrasound and/or X-ray examination, urethral endoscopy, urodynamic examinations (determination of the pressure conditions in the bladder and intestines)
- Prognosis: Relatively good with treatment; high recurrence rate.
What is urethral stricture?
The narrowing of the urethra (urethral stricture) is a common clinical picture in urological practice. It is a remodeling of the urethra with scarring, causing the urethra to narrow. Men are particularly affected by this: Around one percent of them suffer from a narrowing of the urethra. Women suffer from it much less often due to the shorter urethra. A narrowing of the urethra sometimes significantly reduces the quality of life and therefore requires early treatment.
How can a urethral stricture be treated?
The treatment of urethral stricture depends on many factors, especially the length and location of the urethral stricture. The amount of residual urine, possible kidney involvement and existing urinary tract infections also play a role.
As a rule, the therapy for narrowing of the urethra consists of an invasive and sometimes difficult operation, which doctors usually carry out in a specialized clinic. Various surgical techniques are available. None of them are fully suitable for all forms of urethral stricture. To this day, experts disagree about the advantages, disadvantages and long-term results of the various techniques. It is therefore advisable to obtain a second opinion before starting therapy.
Bougienage means stretching and is the oldest of all forms of therapy for a urethral stricture. In this treatment procedure, the doctor inserts a special catheter into the urethra that dilates the urethra (e.g. a balloon catheter). It is even possible for the patient to carry out the bougienage himself after a detailed explanation. A stay in hospital is usually not necessary for this treatment, it can be carried out on an outpatient basis.
Disadvantages of this method are, on the one hand, that the stretching effect only lasts for a certain period of time. As soon as the narrowing occurs again, it is necessary to repeat the stretch. The first relapses can already be expected four to six weeks after the bougienage. In most cases, the intervals between the necessary applications also become shorter over time.
On the other hand, there is a risk that the frequent insertion of the catheter will lead to small injuries, which may aggravate the narrowing of the urethra.
Bougienage cannot be used in patients with acute urinary retention or excessive residual urine production. It is suitable for people who refuse an operation or for whom the anesthetic risk is too high for an operation.
The urethral slit (urethrotomia interna) is usually only an option if the narrowing of the urethra is short (less than one centimeter) and the scarring of the cavernous body (spongiofibrosis) is only slightly pronounced. In this case, it is possible to split the constriction.
For this purpose, the affected person first receives general anesthesia or just spinal cord anesthesia. Then the doctor inserts an endoscope into the urethra to split the scarred constriction with a laser or a knife (“cold knife”) in a controlled manner. After the operation, a catheter usually remains in the urethra for several days as a splint.
The cut in the scar creates a new wound, which in turn leads to scarring. These scars are often larger than the scar originally treated, making the situation worse. Slitting a urethral stricture is therefore only successful in 50 percent of cases. It is possible to repeat them, but this further increases the risk of recurrence. Doctor and patient therefore carefully weigh up the treatment with a slit together.
Reconstruction as an alternative treatment
In the case of a recurring narrowing of the urethra, the doctor performs an open urethral operation – a so-called urethral reconstruction – as an alternative to the urethrotomy. In doing so, he cuts out the constriction of the urethra; If possible, he sews up the two ends of the urethra directly (end-to-end anastomosis). However, this is only possible with a short stretch of the urethra. The success rate is high.
In the case of a long stretch of narrowing of the urethra (narrowing more than about four centimeters long), an operation with a urethral replacement (urethral plastic) is another treatment alternative. This procedure is also used for urethral tears. Doctors use parts of the foreskin or oral mucosa as well as other (mucous) skin areas of the patient to reconstruct the missing section.
The choice of urethral replacement depends on many factors. For example, according to studies, the oral mucosa is in many cases quite suitable for the reconstruction of the urethra. However, after removal of the oral mucosa, complications such as pain and sensory disturbances in the oral cavity occur in some of those affected.
A urethral reconstruction is a very difficult procedure that only an experienced surgeon can usually perform. The operation itself sometimes lasts up to four hours, with a five-day hospital stay to be expected. A complicated narrowing of the urethra often requires several sessions for the operation. There is usually a gap of several months between sessions.
After the operation, a catheter remains in the urethra as a splint for up to three weeks.
Overall, complications of urethral reconstruction are rare. Especially in young men, however, a shortened urethra caused by the operation sometimes leads to erectile problems. The result is that the penis curves downwards. During the operation, care must also be taken to ensure that the erectile tissue is not impaired in its function either directly or indirectly by cutting off the blood supply or by nerve damage.
A stent can be inserted at the site of the narrowing of the urethra using an endoscope. A stent is a small tube made of a metal or plastic mesh that keeps the urethra open. There are permanent stents that remain in the body and temporary stents that the doctor changes after a few months.
Like bougienage, stenting is associated with many potential complications. For example, the stent leads to recurring inflammation in some patients. In addition, it sometimes provokes new scarring. Overall, the long-term results of stenting in urethral strictures are not good. This therapy method is therefore only used in exceptional cases.
What are the symptoms of a urethral stricture?
One of the main symptoms of a urethral stricture is an altered urinary stream. The beam is usually weakened. Often it is also changed in its direction and its form (rotation, diversification). It is usually more difficult for those affected to urinate, which is why they push harder to urinate. This is not necessary if the urine flow is normal.
In addition, with a narrowing of the urethra, urinating when going to the toilet only begins with a delay because the constriction first has to be overcome. After urination, urine often remains in the urinary bladder with a urethral stricture. There is constant pressure on the bladder, or at least the feeling that it is still full. This residual urine formation and the reduced urine stream increase the risk of urinary tract infections.
Affected people are also concerned about sudden interruptions in urination, ” night dripping” and uncontrolled loss of urine (incontinence). Another symptom of urethral constriction is the frequent urge to urinate, whereby usually only small amounts of urine are excreted (pollakiuria). Blood in the urine (hematuria) and urinary stones also often occur with a urethral stricture.
While urinary stones (or kidney or ureter stones) are not noticeable to the person affected, blood in the urine can be recognized by a pink to orange coloration of the urine.
Complication of urinary retention
In severe cases of urethral narrowing, for example, so-called urinary retention occurs, i.e. a complete blockage of the urethra. If this urinary retention persists, severe pain sets in and the urine backs up into the kidneys.
Untreated kidney congestion leads to kidney failure – a life-threatening situation.
In men with urethral narrowing, part of the erectile tissue of the penis (corpus spongiosum) is sometimes affected by the scarring. In the worst case, whole parts of the erectile tissue will scar. In this case one speaks of spongiofibrosis. The consequence is a disturbed erectile function of the penis.
What leads to a urethral stricture?
In around 30 percent of cases, no explanation can be found for the narrowing of the urethra. The disease is idiopathic. Especially in patients under 45 years of age, the cause of the narrowing of the urethra often remains unclear or the stricture is the result of trauma such as a pelvic fracture.
In patients over 45 years of age, it is often medical interventions that have led to injuries and subsequent narrowing of the urethra. Doctors describe such a narrowing of the urethra as iatrogenic – for example after a hypospadias operation. Hypospadias is what doctors call a congenital malformation of the urethra: it is shortened and starts too early – in men, for example, on the underside of the penis, in women in the anterior vaginal vault.
In women, a narrowing of the urethra is usually due to cramping (spasm) of the pelvic floor.
In men, narrowing of the urethra often occurs in the front urethra, i.e. in the section between the pelvic floor and the penis. The posterior urethra, located between the bladder and the pelvic floor, is rarely affected by narrowing. If a narrowing of the urethra occurs here, the cause is usually a traumatic urethral tear or radiation therapy for cancer.
The overall most common cause of urethral stricture is injury. These are not necessarily major damages. Even microscopically small injuries are sufficient for a scarring constriction, such as those that occur when a urinary catheter is placed or during a cystoscopy. However, the majority of these interventions remain without negative consequences.
Nevertheless, caution is required with such invasive diagnostic and therapeutic procedures that affect the urethra. In a common prostate operation, the transurethral prostate resection (TUR-P), up to five percent of those operated on later suffer from a narrowing of the urethra. In women, incontinence operations in particular lead to a urethral stricture. In addition, there are sometimes injuries to the urethra during childbirth with subsequent narrowing of the urethra.
In about 20 percent of cases, a (bacterial) inflammation of the urethra (urethritis) is the cause of the narrowing of the urethra. An important infection in this context is gonorrhea, a sexually transmitted disease caused by bacteria of the Neisseria gonorrhoeae (gonococci) type.
Accidents sometimes lead to a narrowing of the urethra. This applies, for example, to pelvic fractures and blunt injuries in the crotch (“straddle trauma”), such as those caused by a bicycle fall. The urethra is injured either directly or as a result of the pelvic fracture and in extreme cases even tears off.
A narrowing of the urethra is rarely congenital. For example, some people are born with so-called urethral valves (sail-like membranes that narrow the urethra), a narrowing of the urethral opening (meatal stenosis) or abnormal openings of the urethra (hypospadias), which may result in a narrowing of the urethra.
Lichen sclerosus causes five percent of urethral strictures. This is an inflammatory skin disease that leads to hardening of connective tissue, especially on the glans of the penis and the foreskin.
In addition, there are mechanical causes of urethral narrowing such as cancerous growths, polyps, bulges (diverticula), external pressure or a sinking of the pelvic organs (descensus).
How is a urethral stricture diagnosed?
The specialist for diseases of the urinary tract is the urologist. If there is a suspicion of a narrowing of the urethra, the doctor first takes the medical history (aanamnesi) to clarify the cause and asks the following questions, for example:
- What ailments are you suffering from?
- Have you noticed changes in urination?
- Are you aware of diseases of the urinary tract?
- Have you ever had invasive urinary tract examinations or treatments?
He then performs a urine test to rule out a urinary tract infection. This is important, as otherwise both diagnostic and therapeutic measures will result in germs being washed into the bloodstream. Doctors call this urosepsis (“blood poisoning”).
Ideally, the physical examination will identify changes that are already visible on the outside, collect the first indications of a urethral stricture and carry out an initial examination of the kidneys.
The urologist measures the urine flow with the so-called uroflowmeter . The patient urinates with a full bladder in a special toilet that records the flow of urine. With a narrowing of the urethra, urination takes longer and the stream of urine is significantly weakened.
After this examination, ultrasound (sonography) can be used to determine whether there is still urine in the bladder. The narrowing of the urethra itself cannot usually be visualized with this procedure, but an assessment of the bladder is possible. The muscular layer in the wall of the urinary bladder is sometimes thickened in a urethral stricture in an attempt to compensate for the increased resistance caused by the narrowing.
The condition of the kidneys can also be assessed using ultrasound. The doctor pays particular attention to possible urine reflux into the kidneys.
If these tests confirm a narrowing of the urethra, the next step is for the doctor to determine its type, length and location more precisely. For example, he performs a so-called retrograde urethrography : The doctor injects a contrast medium at the exit of the urethra backwards into the urinary tract. Then he takes an x-ray. It allows conclusions to be drawn about the type of urethral narrowing.
Alternatively, a similar X-ray examination with a contrast medium is possible – anterograde urethrography. However, the contrast medium is injected either through a urethral catheter into the bladder or through a direct puncture of the bladder through the abdominal wall. The contrast agent can also be injected into the vein; however, it takes some time before it reaches the bladder. The doctor then uses an X-ray to analyze urination (micturition cystourethrography).
Doctors carry out a urethral endoscopy (urethroscopy) primarily when the urethrography has not given any information about the narrowing of the urethra. The disadvantage of this examination, however, is that it does not allow any statement to be made about the length of the narrowing of the urethra if the narrowing cannot be overcome with the cystoscope.
Doctors carry out so -called urodynamic examinations in special cases: With the help of measuring catheters in the rectum and urinary bladder, they analyze the pressure conditions.
When diagnosing narrowing of the urethra, doctors rule out benign and malignant tumors (e.g. of the prostate) as the cause of the symptoms. It’s also possible that foreign bodies (such as urinary stones) have entered the urethra and are causing a urethral stricture. In unclear situations, they clarify other causes such as megalorether, bladder neck sclerosis or detrusor-bladder neck dyssynergia.
It is also important for therapy planning whether and to what extent the erectile tissue is affected by the scarring change.
What is the prognosis for urethral strictures?
A urethral stricture usually progresses slowly, with scar tissue lengthening and symptoms gradually worsening. Even with treatment, the prognosis is only average. Relapse often occurs within the first two years of initial therapy, necessitating repeat treatment.
The treatment results of a urethral stricture are better the closer the narrowing is to the bladder, the shorter it is and the less frequently the stricture has been treated. Therapy in the event of a relapse is usually more difficult than the initial therapy.
However, an untreated urethral stricture often leads to a loss of kidney function and reduced quality of life due to urinary retention. For this reason, it is important that a narrowing is recognized and treated early.