urethral stricture

Urethral narrowing: description

Urethral stricture (urethral stricture) is a common disease in urological practice. This affects men in particular: around one percent of them suffer from a narrowing of the urethra. Women are much less likely to be due to the shorter urethra. A narrowing of the urethra can significantly limit the quality of life and should therefore be treated early.

Urethral narrowing: symptoms

One of the main symptoms of a urethral constriction is an altered urinary stream. Mostly the beam is weakened. But it can also be changed in its direction and its shape (rotation, fan). Due to the complicated urination, sufferers often have to consciously press in order to release water. In normal urine flow this is not necessary.

In addition, it may happen in a urethral narrowing that the urination at the toilet starts only delayed, since the bottleneck must first be overcome. After urination urine may remain in the urinary bladder during urethral stricture. This residual urine formation and the reduced urinary stream increase the risk of urinary tract infections.

Those affected may also be disturbed by sudden interruptions in urination, “dribbling”, and uncontrolled loss of urine (incontinence). Another symptom of urethral constriction is the frequent urinary urgency, but usually only small amounts of urine are excreted (pollakisuria). Also, blood in the urine (hematuria) and urinary stones are often found in a urethral stricture.

Complication of urinary retention

In severe cases of urethral constriction, a so-called urinary retention can occur, ie a complete blockage of the urethra. When this urinary retention persists, severe pain sets in and the urine can back up to the kidney. An untreated renal congestion leads to kidney failure – a life-threatening situation!

In men with narrowing of the urethra, part of the corpus cavernosum (corpus spongiosum) may be affected by scarring. In the worst case, entire parts of the erectile tissue can scar. In this case one speaks of a Spongiofibrose. The consequence is a disturbed erectile function of the penis.

Urethral narrowing: causes and risk factors

In about 30 percent of cases, no explanation for the urethral narrowing can be found. Also, in patients under 45 years, the cause of urethral stenosis is often unclear, or the stricture is the result of a pelvic fracture or hypospadias surgery. Hypospadias is a congenital malformation of the urethra: it is shortened and begins too early – in men, for example, on the underside of the penis, in women in the anterior vaginal vault.

In patients over the age of 45, it is often medical procedures that have resulted in injury and subsequent narrowing of the urethra.

In women, a narrowing of the urethra is usually due to a spasm (spasm) of the pelvic floor.

The narrowing of the urethra in men often occurs in the anterior urethra, ie in the section between the pelvic floor and the penis. The posterior urethra, located between the bladder and pelvic floor, is rarely affected by a narrowing. If a urethral constriction occurs here, the cause is usually a traumatic urethra rupture or radiotherapy for cancer.

Causes in detail

The most common cause of a urethral narrowing are injury, This does not have to be big damage. Already microscopic injuries are sufficient for a scarred constriction, as they can arise, for example, when laying a bladder catheter or a bladder mirror. The majority of these interventions, however, remain without negative consequences. However, care should be taken with such invasive diagnostic and therapeutic procedures involving the urethra. In a common prostatectomy, the transurethral prostate resection (TUR-P), up to five percent of the patients later suffer from a urethral narrowing. In women, especially incontinence surgery can lead to urethral stricture. In addition, there may be injuries to the urethra during a birth with subsequent urethral narrowing.

In about 20 percent of cases, one (bacterial) Inflammation of the urethra (urethritis) Cause of urethral narrowing. An important infection in this context is gonorrhea (gonorrhea), a sexually transmitted disease caused by Neisseria gonorrhoeae bacteria.

accidents can also lead to a urethral narrowing. This applies, for example, to pelvic fractures and blunt injuries in the stride (“straddle trauma”), such as occur in a bicycle fall. The urethra can be injured directly or due to the pelvic fracture and in extreme cases even tear.

Innate causes are responsible for five to ten percent of all cases of urethral stenosis. For example, some people come with so-called urethral valves (sail-like membranes that narrow the urethra), a narrowing of the urethra opening (meatal stenosis) or miscarriages of the urethra (hypospadias) to the world.

Five percent of urethral strictures are due Lichen sclerosus caused. This is an inflammatory skin disease that leads to connective tissue hardening especially on the glans penis and foreskin.

In addition, there are also mechanical causes for a narrowing of the urethra such as cancerous ulcers, polyps, sloughing (diverticulum), pressure from the outside or sinking of the pelvic organs (descent).

Urethral narrowing: examinations and diagnosis

The specialist in urinary disorders is the urologist. The suspicion of a urethral constriction arises when patients report frequent urinary tract infections and changes in the urinary stream. Sometimes a urethral stricture becomes noticeable only through an acute urinary retention.

To clarify the cause, the doctor will first raise the medical history (anamnese) while asking the patient the following questions, for example:

• Which symptoms do you suffer from?
• Have you noticed any changes in urination?
• Are you familiar with diseases of the urinary tract?
• Have you ever undergone invasive or urinary tract treatment?

Subsequently, a Urinalysis performed to exclude a urinary tract infection. This is important, since otherwise it can come in both diagnostic and therapeutic measures to infiltrate germs in the bloodstream. The doctor calls this a urosepsis (“blood poisoning”).

By the physical examination Already externally visible changes can be identified, first indications of a urethral stricture can be collected and an initial examination of the kidney can be carried out.

The urologist can use the urine flow with the so-called uroflowmeter measure up. The patient must urinate with a full bladder into a special toilet that measures the urine flow. With a narrowing of the urethra urination lasts longer and the urinary stream is significantly reduced.

After this investigation can by means of Ultrasound (sonography) to determine whether urine has remained in the urinary bladder. The urethral narrowing itself is usually not represented by this method, but an evaluation of the bladder is possible. The muscle layer in the wall of the bladder may be thickened at a urethral constriction, in an attempt to compensate for the increased resistance through the constriction. The condition of the kidneys can also be estimated by ultrasound. Pay particular attention to evidence of a return of urine into the kidney.

If these examinations confirm a narrowing of the urethra, its type, length and localization must be precisely determined in the next step. This can be a so-called retrograde urethrography The doctor injects a contrast agent at the exit of the urethra backwards into the urinary tract. Then an x-ray is taken. It allows conclusions about the type of urethral narrowing.

Alternatively, a similar X-ray examination can be performed with contrast agent – the anterograde urethrography, However, the contrast agent is injected either through a urethral catheter into the urinary bladder or through a direct puncture of the bladder through the abdominal wall. Likewise, the contrast agent can be given into the vein, but then it has to wait until it reaches the bladder. Then the urination can be analyzed by an X-ray examination (micturition cystourethrography).

A urethral reflection (urethroscopy) is mainly performed when the urethrography has given no information about the urethral narrowing. The disadvantage of this examination, however, is that it does not allow any statement about the length of the urethral narrowing, if the constriction can not be overcome with the cystoscope.

So-called urodynamic investigations are performed in special cases: With the aid of measuring catheters in the rectum and urinary bladder, the pressure conditions can be analyzed.

As part of the diagnosis of urethral narrowing, benign and malignant tumors (such as the prostate) should be excluded as the cause of the complaints. It is also possible that foreign bodies (such as urinary stones) have entered the urethra and cause urethral stricture. Other causes such as megalourether, bladder neck sclerosis or detrusor bladder neck dyssynergia should be considered in unclear situations.

When clarifying a narrowing of the urethra, it is also determined whether and to what extent the cavernous bodies are affected by the scarring change. This is important for therapy planning.

Urethral narrowing: treatment

The treatment of urethral stenosis must be planned individually. It depends on many factors, especially the length and location of the urethral constriction. But also the amount of residual urine, a possible kidney involvement and existing urinary tract infections play a role.

As a rule, urethral stenosis therapy consists of an invasive and sometimes not easy operation, which is best performed in a specialized clinic. There are several surgical techniques available. None of them are fully suitable for all forms of urethral narrowing. To date, the experts on disagreements and disadvantages and long-term results of the different techniques disagree. It is therefore advisable to seek a second opinion before starting therapy.

Expansion (bougienage)

Bougierung means stretching and is the oldest of all forms of therapy of a urethral stricture. In this procedure, a special catheter is inserted into the urethra, which can dilate the urethra (for example, a balloon catheter). It is even possible that the patient performs the bougienage after a detailed explanation himself.

The main problems of this method are, on the one hand, that the effect of stretching only lasts for a certain time. Once the constriction occurs again, the stretch must be repeated. Four to six weeks after bougienage, first relapses are expected. Over time, the distances between the necessary applications are usually shorter.

On the other hand, the frequent insertion of the catheter can lead to small injuries, which can aggravate the urethral narrowing.

Bougienage should not be used in patients with acute urinary retention or severe residual urine. However, it is suitable for patients who refuse surgery or who are at an increased risk of anesthetized surgery.

Harnröhrenschlitzung

The urethral slit (Urethrotomia interna) is usually only in question, if the urethral narrowing is short (less than one centimeter) and the spongiofibrosis is only slightly pronounced. In this case, the narrowing can be split. For this purpose, the patient first receives a general anesthetic or only spinal cord anesthesia. Then, an endoscope is inserted into the urethra to control the scarred constriction with a laser or a knife controlled (“cold knife”). After surgery, a catheter should remain in the urethra for several days for splinting.

The incision into the scar creates a new wound, which in turn leads to scarring. These scars are often larger than the originally treated scar and exacerbate the situation. The slit of a urethral narrowing is therefore only successful in 50 percent of cases. It can be repeated, but this further increases the risk of relapse. The application of slotting should therefore be carefully considered.

stent

With the help of an endoscope, a stent can be inserted at the site of the urethral narrowing. A stent is a small tube made of a metal or plastic braid that is supposed to keep the urethra open. A distinction is made between permanent stents that can be left and temporary stents that need to be changed or removed after a few months.

Like the bougienage, the stent insert is accompanied by many possible complications. The stent may lead to recurrent inflammation. In addition, he can provoke a new scarring. The long-term results of a stent in urethral narrowing are not good overall. This therapy method is therefore only used in exceptional cases.

reconstruction

In recurrent urethral narrowing usually an open urethral surgery – the urethra reconstruction – performed. The constriction of the urethra is cut out; The two ends of the urethra are tried to suture directly (end-to-end anastomosis). But this is only possible with one short-stretched urethral narrowing, If correctly indicated, the success rate is high.

At a long-stretched urethral narrowing (Narrowed more than about four inches long) is usually an operation performed with urethral replacement (urethral plastic). This procedure is also used for urethral tears. For the reconstruction of the missing part of the foreskin and oral mucosa, but also other (mucous) skin areas of the patient are used. The choice of urethral replacement depends on many factors. For example, according to studies, in many cases the oral mucosa is quite suitable for the reconstruction of the urethra. However, after removal of the oral mucosa various complications such as pain and mood disorders in the mouth can occur.

Urethral reconstruction is a very difficult procedure and should only be done by an experienced surgeon. In a complicated urethral narrowing, the surgery can also be performed in several sessions. There should be several months between each session.

After surgery, a catheter remains in the urethra for up to three weeks as a splint.

Overall, complications in a urethral reconstruction are rare. Especially in young men but shortened by the operation urethra can lead to erection problems. The result is that the penis curves downwards. During surgery, care must also be taken to ensure that the cavernous bodies are not disturbed in their function either directly or indirectly by blocking the blood supply or nerve damage.

Urethral narrowing: disease course and prognosis

An untreated urethral narrowing can lead to renal dysfunction and impaired quality of life through urinary retention. For this reason, it is important that a narrowing be recognized early and treated.

However, after successful treatment, a urethral constriction may recur. The therapy of such a relapse is usually more difficult than the first therapy.

Altogether: The treatment results of a urethral stricture The closer the narrowing is to the bladder, the shorter it is and the less the stricture has been treated, the better.