Trabeculated Bladder: Causes, Symptoms, and Treatment

A trabeculated bladder is a bladder with a stiff, thickened wall. It mainly occurs when the repeated or prolonged blockage of urine flow (called a bladder outlet obstruction) forces the bladder to work harder to push urine past the blockage.

Over time, the increased pressure causes the formation of scar tissues and other changes that reduce the bladder’s elasticity. This loss of elasticity can increase the amount of urine left in the bladder, causing it to backflow into the kidney and causing a kidney infection.

Treatment is focused on removing the blockage and improving urine flow with medications, urinary catheters, or surgery.

Signs and Symptoms

The symptoms of bladder trabeculation are mainly due to bladder outlet obstruction (BOO). BOO is the blockage of the muscular passageway (called the bladder neck) that connects the bladder to the urethra (the tube through which urine exits the body).

Signs and symptoms of a trabeculated bladder include:

• Difficulty urinating despite a strong urge to urinate
• Needing to go to the bathroom frequently to pee (urinary frequency)
• A slow urine stream
• Low urine output
• Stop-and-go urination
• Dribbling after urination
• A feeling of bladder fullness after urination (incomplete evacuation)
• Frequent urination at night (nocturia)
• Pelvic pain and discomfort

What Causes Bladder Trabeculation?

Bladder trabeculation occurs when urine does not flow from the bladder as it is meant to and is instead retained in the bladder. The retention causes the bladder to swell, placing excessive stress on the bladder wall and, most specifically, the muscle that contracts the bladder (called the detrusor muscle).

Over time, the stress not only causes the buildup of scar tissue, called fibrosis, but also an increase in muscle mass, called hypertrophy. (This is not unlike what happens when skeletal muscles grow when placed under stress from exercise.)

However, with trabeculation, the sustained pressure can cause tiny pockets (known as diverticula) to spontaneously bulge out of weakened spots in the bladder wall.

The tissues of the bladder itself will start to change, becoming not only thicker but less pliable. Blood vessels will also start to shrink, reducing blood flow and causing the progressive loss of muscle mass even as the bladder wall becomes thicker.

Without the means to push urine out of the bladder, urine can start to reflux (backflow) to the kidneys, causing kidney damage.

Bladder Outlet Obstruction

The main cause of trabeculated bladder is BOO, which may be the result of:

• Benign prostatic hyperplasia (BPH): Also known as an enlarged prostate, this mainly affects males over 60.
• Pelvic organ prolapse (POP): This is due to the collapse of pelvic floor muscles, causing the bladder, uterus, and other pelvic organs to drop out of their normal position.
• Urethral stricture: This is the narrowing of the urethra caused by repeated urinary tract infections (UTIs), kidney stones, prostatitis, urinary catheters, or urinary surgery.
• Urethral venous thrombus: This is the formation of a blood clot (thrombus) in the veins servicing the urethra, most common in females.
• Hydronephrosis in pregnancy: This is the backup of urine during pregnancy caused when the growing fetus compresses the bladder outlet.
• Posterior urethral valve: This rare condition present at birth is seen in males. It causes extra flaps of tissue inside the urethra that can obstruct urine flow.
• Inverted urothelial papilloma: This rare but benign (noncancerous) tumor can form in the bladder neck or urethra, causing urinary blockage.
• Urothelial carcinoma: This rare type of urinary cancer, more common in males, can obstruct urine flow directly or by creating multiple kidney or bladder stones.

Neurogenic Bladder

BOO is not the only cause of a trabeculated bladder. Less commonly, it can occur with a condition called neurogenic bladder, in which the nerves that control urination are damaged. It can either lead to an overactive bladder or an underactive bladder.

With an underactive bladder, the loss of detrusor muscle function can cause the bladder to overfill, resulting in urinary retention (the inability to fully empty the bladder). This can place the same level of stress on the bladder as BOO, leading to the thickening and scarring of the bladder wall.

Causes of neurogenic bladder include:

How Is It Diagnosed? 

Bladder trabeculation is commonly investigated in people with BOO and neurogenic bladder. As a consequence of these conditions—rather than its own free-standing condition—bladder trabeculation is diagnosed based on the thickness of the bladder wall and the proportion of the bladder affected.

Two tests are commonly used for this:

• Voiding cystourethrogram (VCUG): This imaging technique involves the delivery of a fluorescent dye into your bladder using a urinary catheter. As you pee it out, an X-ray measures the thickness of the bladder wall in millimeters (mm).
• Cystoscopy: This involves the insertion of a flexible scope into the urethra to look inside your bladder. A cystoscope can help determine the extent of hypertrophy and detect smaller diverticula.

Together, these tests help grade the severity of bladder trabeculation and direct the appropriate course of treatment. Trabeculation is graded on a scale of 0 to 3, as follows:

• Grade 0: No signs of trabeculation
• Grade 1: Bladder wall thickness of more than 3 millimeters (mm) but less than 5 mm, with less than 50% of the bladder affected
• Grade 2: Bladder wall thickness of between 5 mm and 10 mm, with more than 50% of the bladder affected
• Grade 3: Bladder wall thickness of over 10 mm, with more than 50% of the bladder affected

A urodynamic study can help determine the diagnosis. This series of tests measures bladder function, using uroflowmetry to measure how fast and forcefully you pee and post-void residual (PVR) to measure how much urine is left in the bladder after you pee.

How Is It Treated?

The treatment of a trabeculated bladder is focused on treating or managing the underlying condition. This may involve clearing an obstruction and using medications or surgery to normalize urine flow and prevent kidney damage.

Treating Bladder Outlet Obstruction

BOO treatment can vary and will depend on the cause. Some are treated with drugs, while others require specialist procedures or surgery.

Examples include:

• An enlarged prostate may be treated with alpha-blockers like Flomax (tamsulosin) or a prostate surgery called transurethral resection of the prostate (TURP).
• Pelvic organ prolapse may be treated with a removable device called a vaginal pessary or a reconstructive surgery called anterior vaginal repair.
• Urethral strictures can be treated with procedures like urethrotomy (stretching the urethra during cystoscopy) and urethroplasty (urethral reconstruction surgery).
• Posterior urethral valves can be treated by removing the excess tissue with electricity (electroresection) or heat (fulguration) during cystoscopy.
• Tumors can be removed with electroresection, fulguration, or laser surgery. Radiation with or without chemotherapy is commonly used when there is cancer.

Not all cases of bladder trabeculation need treatment. For instance, trabeculation caused by pregnancy will typically resolve once the baby is delivered.

Treating Neurogenic Bladder

Treating trabeculation with a neurogenic bladder can be challenging because the underlying cause is often incurable. Therefore, treatment is mainly aimed at normalizing urine flow and preventing complications.

Among the possible tools and techniques are:

• Urinary catheters can help empty the bladder and avoid overfilling. They may involve either an intermittent catheter or a Foley catheter used for continuous urine drainage.
• Urethral stents are tiny plastic tubes inserted during cystoscopy, which improve urine flow by keeping the urethra open.
• Bladder sphincterotomy is a surgery used to relieve urinary retention by cutting the urinary sphincter muscle that controls the flow of urine out of the bladder.
• Ureterostomy is a surgery in which the tubes from your kidneys (ureters) are cut and rerouted through a hole in your belly to drain urine into an external bag.

Long-Term Outlook

The outlook of bladder trabeculation varies depending on the amount of tissue remodeling that has occurred. Under normal circumstances, remodeling is the process in which injured tissues are repaired using a structural protein called collagen.

However, if the injury is persistent, the normal cellular framework—called the collagen matrix—can start to fall apart as more and more collagen piles up. The disorganized remodeling is what causes fibrosis.

With bladder trabeculation, the outlook is based largely on the duration and severity of urinary retention. With some conditions, such as hydronephrosis in pregnancy, the damage may be low-grade and fully reversible. With others, such as a spinal cord injury, the damage may be high-grade and permanent.

Complications of Bladder Trabeculation

The appropriate treatment of a trabeculated bladder can help protect the kidneys and prevent disease complications. This includes a condition called vesicoureteral reflux (VUR), in which urine backflows from the bladder to the kidneys. ‘

Left untreated, VUR can increase the risk of potentially severe conditions like:

How to Avoid Complications

If you are diagnosed with bladder trabeculation, there are things you can do to avoid disease progression. Chief among these is fully emptying the bladder; doing so reduces stress on the bladder wall and prevents further scarring.

There are a couple of techniques that can help:

• Timed voiding: This involves going to the bathroom to pee on a set schedule, roughly every two to three hours, even if you don’t feel like going.
• Double voiding: This involves sitting on the toilet a minute or so after urination and leaning forward. This compresses the bladder and helps squeeze out a little more urine.

Can You Prevent a Trabeculated Bladder?

It is not always possible to avoid a trabeculated bladder, particularly with conditions like neurogenic bladder or congenital malformations. However, there are five simple lifestyle changes that may help reduce your risk:

• Lose weight: Excess weight can weaken pelvic floor muscles, contributing to pelvic organ prolapse. With BPH, excess body fat can increase levels of hormones that stimulate the growth of prostate cells. Obesity also increases the risk of kidney stones.
• Eat more fiber: Straining due to chronic constipation can also weaken the pelvic floor muscles and lead to prolapse. Eating more fruits, vegetables, whole grains, beans, and lentils can help you meet your daily fiber goals.
• Quit smoking: Smoking can cause chronic coughing that weakens pelvic floor muscles. Cigarette smoke is also known to increase the levels of a hormone called dihydrotestosterone (DHT) associated with BPH.
• Control your blood sugar: If you have diabetes, exercising, losing weight, eating a healthy diet, and taking prescribed medications can greatly reduce your risk of diabetic nephropathy.
• Use catheters safely: You can reduce your risk of UTIs by cleaning your catheter every day, washing your hands before and after touching a catheter, keeping the catheter bag lower than the bladder, and emptying the urine bag every eight hours or when it is full.

Summary

A trabeculated bladder occurs when the bladder wall thickens due to a bladder outlet obstruction or a neurogenic bladder. This makes the bladder less elastic, leading to urinary problems, pelvic pain, and an increased risk of urinary tract infections (UTIs). Left untreated, bladder trabeculation can lead to high blood pressure, urinary incontinence, and kidney damage.

Bladder trabeculation is mainly diagnosed with a voiding cystourethrogram (VCUG) which can measure the thickness of the bladder wall. Treatment differs based on the underlying cause but may include medications like Flomax, urinary catheters or stents, and different surgeries to unblock obstructions or help widen the urethra.