What Are the Causes of Urethral Strictures?

A urethral stricture occurs when the urethra, the tube that carries urine out of the body, narrows due to scarring. According to the National Institute of Diabetes and Digestive and Kidney Diseases, scarring usually occurs following an injury or damage to the penis. While the disease can occur in women, it is more common in men, due to the longer length of the urethra in males.

Symptoms

• Symptoms of a urethral stricture include reduced urine flow and output, spraying when urinating, painful urination and incomplete emptying of the bladder. If you aren't able to completely empty your bladder, the pool of urine remaining inside may cause infections of the kidney, bladder or prostate. You may also be prone to developing urinary tract infections if you have a stricture.

Trauma

• Injury to the urethra can occur when the part of the urethra located below the pubic bone strikes a hard object. Known as a straddle injury, this type of damage commonly occurs when a male bicycle rider falls on the bicycle's crossbar. As the injury heals, scarring can occur, resulting in a stricture. Pelvic fractures, or any type of injury in the pelvic area, can damage the urethra. It is also possible to develop a stricture from damage caused by the insertion of a urinary catheter (a small tube inserted into the urethra to drain urine from the bladder) or a cystoscope (a flexible probe with a camera attached that is used to help diagnose urinary diseases and conditions).

Infections

• Sexually transmitted diseases can cause urethritis, an inflammation of the urethra. If urethritis is not treated promptly, scarring can occur. Infections and scarring can also occur with long-term urinary catheter use. While scarring is a possibility following an infection, the majority of infections heal without causing strictures.

Lichen sclerosus

• Lichen sclerosus is a skin disease that primarily affects the anal and genital areas. The disease is characterized by small white spots that form on the skin and grow larger with time. Eventually, the skin on the spots becomes crinkled and thin, causing bruising and scarring. When scarring occurs on the penis, strictures can occur. According to the National Institute of Arthritis and Musculoskeletal and Skin Diseases, an exact cause for lichen sclerosus is not known, but the disease may occur due to hormone and immune system problems.

Other Causes

• Strictures can result from scarring after pelvic surgery, including kidney, prostate or bladder procedures. Some children are born with urinary strictures or other congenital defects of the urethra or penis, and while surgery is often successful in correcting these problems, the surgery itself can result in strictures due to scarring. New scarring can also occur following surgery to correct a stricture. If you have had gender reassignment surgery, you may develop a stricture following surgery. In some cases, there is no known cause for the stricture.