The main clinical manifestations of urethral stricture are: difficulty in urination, gradual thinning of the urine line, and in severe cases, urinary retention. The male urethra is usually divided into 4 parts according to the anatomical structure: the prostatic urethra, the membranous urethra, the bulbous urethra and the penile urethra, and the etiology of strictures in different parts varies slightly.
The clinical causes of urethral stricture are
- Traumatic urethral stricture
The most common cause of bulbar urethral stricture is traumatic pelvic fracture. When the bony structures of the pelvis are fractured or displaced, the fragile bulbous and membranous urethra is usually squeezed, resulting in a narrowing of the urethral canal and, in the distant future, the formation of urethral scarring. These patients often find difficulty with urethral tube placement when catheterization is attempted in the emergency resuscitation room, along with combined urethral bleeding, and usually require a cystostomy by a urology specialist to address immediate post-injury urinary drainage problems. Since the etiology is relatively clear, the surgical approach to urethral repair can be determined in the long term depending on the condition of the urethral stricture.
Another common cause of bulbar urethral stricture is a straddling injury. For example, a fall from a height or crossing an obstacle can cause the pubic tissues to hit each other with hard objects and suffer instantaneous squeezing pressure, leading to soft tissue damage to the bulb of the urethra and narrowing, which can cause urethral bleeding and difficulty in urination in mild cases or urethral rupture and perineal hematoma in severe cases.
2、Inflammatory urethral stricture
The clinical manifestation of this type of urethral stricture is repeated urinary tract infection, and the inflammation itself will cause symptoms such as urinary urgency, frequency, painful urination and difficulty in urination. In addition, physical and chemical factors also aggravate the formation of infection leading to urethral stricture, for example, long foreskin, prepuce can lead to glans surface skin mucosa congestion, edema ulceration, long-term stimulation can induce specific skin lesions – mossy sclerosis or even squamous carcinoma, these external inflammatory changes will gradually invade the urethral orifice, making the urethral orifice The clinical symptoms are further aggravated by narrowing, and in severe cases, the entire urethra of the penis is accumulated and a long segment of urethral stricture appears, and late treatment relies on grafts such as oral mucosa for urethral enlargement and shaping.
3、Congenital urethral stricture
Congenital urethral strictures often occur in young children or adolescents, commonly in patients with hypospadias and urethral anomalies, and the stricture segment often occurs in the urethra of the penis, usually due to early detection and urethral repair surgery. However, in recent years, it has been reported in the literature that some patients with congenital urethral strictures continue to have urethral stricture changes in adulthood and may need to see a doctor again to assess the need for a second urethral enlargement procedure.
- Medically induced urethral strictures
With the development of urological lumpectomy techniques, the increasing number of procedures such as transurethral resection of the prostate and transurethral resection of bladder tumors has also led to a gradual increase in the incidence of medically induced urethral strictures.
On the one hand, surgical cutting of the prostate tissue itself brings about damage to the urethra of the prostate, and most patients heal well after surgery, but a very small number of patients still develop scar contracture in the surgical area, which leads to stricture of the urethra of the prostate.
On the other hand, various endoscopic procedures can also cause mucosal damage to the urethra of the penis and the urethra of the bulb to varying degrees if the operation is not performed with proper intensity or method, and in a small number of patients, the urethra can also be narrowed due to scar formation. In addition, due to various medical conditions or surgical procedures, some patients need indwelling catheters, which may cause urethral injury and infection when inserting or removing the catheter due to special factors such as prostate enlargement in patients, which may in turn cause urethral stricture.
