Bladder Diverticulum
Causes, Symptoms, Diagnosis, Treatment and Support
What is Bladder Diverticulum?
A urinary bladder diverticulum is a sac-like pouch that forms in the wall of the bladder, protruding outward from the normal bladder structure. These pouches, or diverticula, may be congenital (present at birth) or acquired later in life due to conditions that increase bladder pressure, such as urinary tract obstructions, bladder outlet obstruction, or prostate enlargement. While small bladder diverticula often go unnoticed and may not cause symptoms, larger or multiple diverticula can lead to complications, including urinary tract infections, bladder stones, or difficulties with bladder emptying. Diagnosis usually involves imaging tests like ultrasound or cystoscopy, and treatment varies based on size and symptoms, ranging from regular monitoring to surgical intervention.
Causes and Risk Factors of Bladder Diverticulum
Bladder diverticula can develop due to various causes and risk factors, which primarily include structural or pressure-related issues affecting the bladder wall. These pouches in the bladder wall can be congenital or acquired:
1. Congenital Causes
- Congenital Diverticulum: These are present from birth and result from a weakness in the bladder wall that fails to close properly during fetal development. They are less common and often singular. Congenital bladder diverticula are usually asymptomatic but can lead to complications if they enlarge or become infected.
2. Acquired Causes and Risk Factors
- Bladder Outlet Obstruction (BOO): One of the most common causes of acquired bladder diverticula, BOO often results from conditions like benign prostatic hyperplasia (BPH) in men, which causes an obstruction at the bladder neck. This obstruction forces the bladder to exert more pressure to expel urine, gradually weakening the wall and leading to the formation of diverticula.
- Neurogenic Bladder Disorders: Conditions such as spinal cord injuries, multiple sclerosis, or Parkinson’s disease can cause neurogenic bladder dysfunction. When the bladder’s nerve supply is compromised, it may not empty properly, leading to increased pressure within the bladder and increasing the risk of diverticula.
- Urethral Strictures: Narrowing or scarring of the urethra can obstruct urinary flow, resulting in increased bladder pressure and predisposing the bladder wall to diverticulum formation.
- Chronic Urinary Tract Infections (UTIs): Recurrent infections can cause inflammation of the bladder wall, leading to weakening over time. This increases the likelihood of diverticulum formation, particularly if infections are left untreated.
3. Other Contributing Factors
- Age: Diverticula are more common in older adults due to natural weakening of the bladder wall with age.
- Gender: Men are at higher risk, largely due to conditions like BPH, which increases bladder outlet resistance.
- Repetitive Catheterization: Frequent catheter use or repeated urinary procedures can irritate and weaken the bladder wall, increasing susceptibility to diverticula.
Bladder diverticula may not initially present symptoms but can lead to significant complications if they cause urine retention or become infected.
Signs and Symptoms of Bladder Diverticulum
The signs and symptoms of bladder diverticulum vary depending on the size and potential complications associated with the diverticulum. Many small bladder diverticula are asymptomatic and discovered incidentally during imaging for other conditions. However, larger or infected diverticula can cause a range of urinary symptoms:
1. Difficulty in Urination
- Incomplete Bladder Emptying: Diverticula may trap urine, leading to a sensation of incomplete bladder emptying. This is one of the most common symptoms, as diverticula prevent the bladder from fully expelling urine.
- Straining or Hesitancy: Patients may need to strain to initiate or complete urination, as the bladder has to overcome the pressure from the diverticulum.
2. Increased Frequency and Urgency of Urination
- Frequent Urination: Due to incomplete emptying, patients may need to urinate more frequently to manage retained urine, especially during the night (nocturia).
- Urinary Urgency: The sensation of needing to urinate immediately, often caused by irritation or inflammation in the bladder.
3. Recurrent Urinary Tract Infections (UTIs)
- Diverticula can trap urine, creating a breeding ground for bacteria, which can lead to repeated UTIs. Symptoms of UTIs include burning during urination, cloudy or strong-smelling urine, and pelvic discomfort.
4. Hematuria (Blood in Urine)
- Diverticula may become inflamed or infected, leading to blood in the urine (hematuria). This can be visible (macroscopic) or detectable only through a urine test (microscopic).
5. Pain and Discomfort in the Lower Abdomen
- Some patients may experience pain or pressure in the lower abdomen, especially if the diverticulum is large or infected.
6. Bladder Stones or Urethral Obstruction
- Diverticula can harbor stones, which may cause pain and discomfort or even obstruct urine flow, leading to further complications like acute urinary retention.
Bladder diverticulum symptoms often overlap with those of other bladder or urinary tract conditions, making diagnostic imaging essential for accurate diagnosis and appropriate treatment planning.
Diagnosis and Medical Evaluation of Bladder Diverticulum
The diagnosis and evaluation of bladder diverticulum typically involve a combination of imaging studies and sometimes direct visualization techniques. This diagnostic approach helps determine the size, location, and impact of the diverticulum on urinary function. Here are the primary methods used:
1. Medical History and Physical Examination
- Symptoms Review: The doctor will review any urinary symptoms such as difficulty urinating, frequent infections, or hematuria. A physical examination may also be performed to assess any tenderness or discomfort in the lower abdomen.
2. Imaging Studies
- Ultrasound (Sonography): This non-invasive test uses sound waves to visualize the bladder and is often the initial step in identifying bladder diverticula. Ultrasound can detect fluid-filled sacs (diverticula) and assess their size.
- Voiding Cystourethrogram (VCUG): A specialized X-ray technique where a contrast dye is introduced into the bladder. As the patient urinates, X-rays are taken to reveal the structure of the bladder, diverticulum location, and any urine flow abnormalities or reflux.
- Computed Tomography (CT) Scan: CT imaging provides detailed cross-sectional images and can be useful for identifying large or complex diverticula. It’s especially helpful when assessing potential complications, like bladder stones or other obstructive issues.
- Magnetic Resonance Imaging (MRI): MRI can offer detailed soft tissue visualization and is sometimes used when other imaging results are inconclusive or if the diverticulum’s structure and surroundings require further investigation.
3. Cystoscopy
- Procedure: Cystoscopy involves inserting a small scope through the urethra to examine the bladder interior. This method allows for direct visualization of the diverticulum and is useful for assessing size, position, and associated complications like stones or infection within the diverticulum.
- Biopsy Option: If there’s a suspicion of malignancy or abnormal tissue, a biopsy may be taken during cystoscopy to check for any cancerous or pre-cancerous cells.
4. Urine Tests
- Urinalysis and Urine Culture: These tests detect infections or blood in the urine, which can be symptoms associated with bladder diverticulum. A urine culture can also help identify specific bacteria if infections are recurrent.
5. Renal Function Tests
- In some cases, tests like blood urea nitrogen (BUN) and creatinine levels may be evaluated to check if kidney function has been affected by long-standing urinary obstruction or infections associated with a bladder diverticulum.
Summary
The diagnostic process for bladder diverticulum usually starts with imaging studies like ultrasound and VCUG for visualization, followed by cystoscopy for a detailed view and potential biopsy if necessary. Urine tests aid in evaluating infections or hematuria, while renal function tests check for any effect on kidney health. These steps help determine the best treatment approach based on the diverticulum’s impact on bladder function and the patient’s overall health.
Treatment of Bladder Diverticulum
The treatment of bladder diverticulum depends on factors such as size, symptoms, and any complications like recurrent infections or bladder stones. For small, asymptomatic diverticula, monitoring may be sufficient, but larger or symptomatic cases often require intervention. Here are the main treatment options:
1. Conservative Management
- Observation and Monitoring: For small, asymptomatic bladder diverticula, periodic monitoring through imaging tests may be advised to ensure there is no growth or development of symptoms.
- Antibiotic Therapy: If the diverticulum causes recurrent urinary tract infections (UTIs), antibiotics may be prescribed to manage infections.
2. Surgical Treatment
- Surgical intervention is considered for larger or symptomatic diverticula, especially those causing complications like urinary retention, infections, or bladder stones.
a. Diverticulectomy
- Procedure: This is the surgical removal of the diverticulum. It can be done through different techniques, depending on the diverticulum's size and complexity:
- Open Surgery: A traditional approach involving an incision in the abdomen to access and remove the diverticulum.
- Minimally Invasive (Laparoscopic or Robotic) Surgery: A less invasive approach that uses small incisions and robotic or laparoscopic tools. This method is associated with a quicker recovery, less pain, and reduced hospital stay.
- Indications: Diverticulectomy is typically performed for large diverticula or those causing severe symptoms or recurrent infections.
b. Transurethral Surgery
- Endoscopic Transurethral Incision: For smaller diverticula, endoscopic surgery can be used to create an opening between the diverticulum and the bladder to improve urine drainage and reduce infection risk. This procedure is performed through the urethra and does not require external incisions.
- Urethral Stenting: A stent may be placed temporarily to keep the passage between the bladder and the diverticulum open, improving drainage and reducing pressure.
3. Management of Underlying Causes
- Addressing Bladder Outlet Obstruction (BOO): If the diverticulum results from bladder outlet obstruction, such as benign prostatic hyperplasia (BPH), treating the underlying cause can help reduce the symptoms and prevent further complications. Treatment options for BOO may include medications or surgery (e.g., transurethral resection of the prostate).
- Neurogenic Bladder Treatment: If neurogenic bladder dysfunction is a contributing factor, therapies to manage bladder function, such as medications, clean intermittent catheterization, or nerve stimulation, may be incorporated into the treatment plan.
4. Postoperative Care and Monitoring
- Regular Follow-up: Post-surgical monitoring with imaging and urinary assessments helps ensure proper healing and detect any recurrence or development of new diverticula.
- Infection Prevention: Prophylactic antibiotics may be used postoperatively to prevent infection, and patients are advised to maintain good hydration and follow any urologist-recommended practices to promote bladder health.
Summary
Treatment for bladder diverticula ranges from conservative management with monitoring and antibiotics to surgical options such as diverticulectomy and endoscopic procedures. Addressing underlying conditions that contribute to diverticulum formation is also essential for comprehensive management and long-term symptom relief. The choice of treatment depends on the diverticulum's size, the severity of symptoms, and the presence of any complications.