Urethral strictures in men: causes and pathogenesis

Causes of urethral stricture in men

The urethra strictures in men can be caused by a sexual trauma that occurs when the cavernous bodies break (fracture) of the penis, also when masturbating with various foreign bodies.

Inflammatory strictures associated with gonorrhea are now less common than before, due to the appointment of an effective antibiotic treatment. These strictures more often affect the bulbous and less frequent penile sections of the urethra, the constrictions most often occur long, sometimes with the spread to the entire spongy department.

The significance of chlamydia and ureaplasma (nonspecific urethritis) in the development of inflammatory narrowing of the urethra remains unclear.

Xerotic oblteriruyuschy balance (lichen sclerosus) refers to non-venereal infections, but its etiological factor remains unclear.

The scleroatrophic process first affects either the skin of the glans penis, or the inner sheet of the prepuce and only then passes to the external opening of the urethra (meatus) and the scaphoid fossa, causing the development of meatostenosis. The lesion can spread to a significant part of the urethra spinal section, causing the development of extensive and severe stricture. Although the use of antibiotics in these patients is appropriate for limiting obstructive urination symptoms, the literature data do not confirm the limiting role of antibiotic therapy in the progression of the urethral stricture.
The cause of inflammatory stricture can serve as a urethral catheter, which contributes to the development of acute and chronic urethral infections, and therefore the stricture of the urethra. An invasive nosocomial infection plays a special role here.

Congenital strictures of the urethra occur in the form of meatostenosis with hypospadias, as well as at the border of the bulbous and membranous urethra where two fetal embryos merge. Identified in early childhood, the diagnosis is established when excluding traumatic and infectious factors.

Idiopathic strictures, i.e. Strictures of unclear etiology, are met more often in the bulbous department. According to statistics, their frequency reaches 11-15%, when in an anamnesis in an adult male there are no injuries, no urethritis, no catheterization, etc.

[1], [2], [3]

Pathogenesis of urethral stricture in men

Injuries of the membranous urethra in fractures of pelvic bones

Fractures of the pelvic bones, ruptures of the muscles of the urogenital and pelvic diaphragms cause, as a rule, a complete break of the urethra, ie a rupture through all the layers along the entire length of the circumference, with a divergence of the ends of the urethra to a smaller (0.5 cm) or larger cm) distance. The hematoma in the area of the urethra trauma dissolves and is replaced by fibrosis. The scar zone has always clear boundaries with normal tissues. The heavier the injury, the longer the hematomas will be resorbed and the collagen scar fields will form. Therefore, the recovery time after a light and moderate severity of pelvic pelvic injuries with their favorable rehabilitation and uncomplicated urinary tract trauma, in time and complete urinary diversion of urine can be 2.5-3 months. Severe bone trauma and / or complications from the urinary tract (urinary pelvic infection, pelvic or paraurethral abscess with an opening) shift the recovery period of the urethra to 4-6 months after injury.

Injuries of bulbous urethra with blunt trauma of perineum

Damage can affect only the spongy body without damage to the mucosa or be penetrating, i. E. With rupture of the mucosa. Trauma can be with a full break of the urethra (a divergence of the ends, as a rule, insignificant: 0.5-1 cm) or partial, when part of the urinary tract is preserved. In any case, a periurethral hematoma is formed either in the form of tissue impregnation with blood, or in the form of a blood cavity. The resorption of hematomas will occur mainly within 2, a maximum of 3 weeks. By 6-8 weeks, a dense scar of the urethra and periurethral tissues will form. Restoration of the urethra is possible and appropriate after 6-8 weeks after trauma. If there is an infection in the area of trauma and drainage of the inflammatory focus, the recovery period of the urethra moves to the end of the 3rd month after the injury.

A distinctive feature of the inflammatory strictures of the spongy part of the urethra is:

1. as a rule, the latent beginning of development;
2. slow gradual progression over months and years
3. lack of clear boundaries for damage to spongy tissue;
4. progression of inflammation and spongiofibrosis after surgical treatment of inflammatory strictures of the urethra;
5. periurethral fibrosis with muscle and perineal cell damage;
6. inflammatory lesions of the skin of the perineum, scrotum, penis in a number of cases.

The role of urinary infiltration in the development of inflammatory strictures is exaggerated. Of course, after desquamation of the epithelium, the subepithelial connective tissue contacts the urine during the exercise, but not so much the urine itself is harmed as much as the bacterial factor that, without the urine, is capable of causing destruction of the tissues with subsequent fibrosis. It is the peculiarity of the structure of the spongy body (the "bundle" of venous trunks) that promotes the progression of inflammation through the body and the absence of clear boundaries of the lesion.