Bladder Stones

Overview

Bladder stones (vesical calculi) are hard mineral masses that form when urine remains in the bladder too long and becomes concentrated. Unlike kidney stones, which develop in the kidneys and may travel into the bladder, bladder stones typically form directly within the bladder itself due to incomplete emptying.

The condition occurs most commonly in men over age 50, primarily because benign prostatic hyperplasia (BPH) obstructs urine flow and prevents complete bladder emptying. The residual urine becomes concentrated, allowing minerals to crystallize and eventually form stones. While less common than kidney stones, bladder stones cause significant discomfort and can lead to recurrent infections, bladder damage, and urinary obstruction if left untreated.

Bladder stones vary in composition. Uric acid stones are most common in adults and form in acidic urine. Calcium oxalate and calcium phosphate stones develop frequently, particularly when infection is present. Struvite stones, composed of magnesium ammonium phosphate, are strongly associated with urinary tract infections. Cystine stones are rare and result from an inherited metabolic disorder.

Symptoms

The hallmark symptom of bladder stones is an interrupted urine stream that starts and stops abruptly as the stone moves in and out of the bladder outlet. Many patients report difficulty initiating urination, particularly when the stone blocks the internal urethral opening. Pain during urination often intensifies toward the end of voiding as the bladder contracts and pushes the stone against sensitive tissue.

Lower abdominal and pelvic pain typically worsens with movement, exercise, or activities involving bouncing motions. Men commonly experience referred pain at the tip of the penis or in the scrotum. Frequent urination, especially at night, along with persistent urinary urgency are common complaints.

Blood in the urine (hematuria) occurs when stones irritate the bladder lining. Urine may appear cloudy or unusually dark. Recurrent urinary tract infections develop because stones harbor bacteria and prevent complete bladder emptying. Some patients experience urinary incontinence. Symptoms characteristically worsen with physical activity and at the end of urination when the stone settles against the bladder outlet.

Causes

Bladder outlet obstruction represents the most common cause. Benign prostatic hyperplasia in men compresses the urethra and prevents complete bladder emptying. Urethral stricture narrows the urinary passage. Bladder neck contracture, often following prostate surgery, creates similar obstruction.

Neurogenic bladder conditions impair nerve signals that coordinate bladder function. Spinal cord injuries, multiple sclerosis, Parkinson’s disease, stroke, and diabetic neuropathy all affect bladder emptying. Patients with neurogenic bladder frequently retain significant urine volumes, creating ideal conditions for stone formation.

Anatomic abnormalities contribute to stone development. Bladder diverticula are outpouchings where urine stagnates and stones collect. Cystocele in women causes the bladder to prolapse, trapping residual urine. Prior bladder surgery may alter anatomy in ways that impair emptying.

Foreign bodies serve as nucleation sites for mineral deposition. Long-term urinary catheters, surgical sutures, and mesh materials can all become encrusted with minerals. Kidney stones that pass into the bladder but fail to exit through the urethra may remain and enlarge. Chronic dehydration concentrates urine minerals, while recurrent infections alter urine chemistry to favor stone formation.

Diagnosis

Evaluation begins with a thorough medical history focusing on urinary symptoms and a physical examination including prostate assessment in men and pelvic examination in women. The goal is both to confirm stones and to identify the underlying cause of incomplete bladder emptying.

Ultrasound serves as the first-line imaging study. This non-invasive test detects most bladder stones without radiation exposure and also evaluates how completely the bladder empties. CT scan provides greater sensitivity and can identify stone composition, assess the entire urinary tract, and reveal underlying causes. Plain X-rays may detect calcium-containing stones but miss radiolucent uric acid stones.

Cystoscopy allows direct visualization of the bladder interior through a small camera passed through the urethra. This confirms stone presence, determines size and number, and evaluates the bladder and prostate. Cystoscopy can often be combined with treatment in a single procedure.

Laboratory studies include urinalysis to detect blood, infection, and crystals, along with urine culture if infection is suspected. Blood tests assess kidney function and measure calcium and uric acid levels. Post-void residual measurement quantifies how much urine remains after urination, directly assessing bladder emptying.

Treatment

Effective treatment requires removing the stones and addressing the underlying cause to prevent recurrence. Small stones under 5mm may pass spontaneously with increased fluid intake and medications that relax the bladder outlet, though this approach requires careful monitoring.

Cystolitholapaxy is the most common procedure. A urologist passes a cystoscope through the urethra into the bladder and fragments the stone using laser, ultrasonic, or mechanical energy. The fragments are then removed or irrigated out. This outpatient procedure requires no external incisions and offers rapid recovery. When BPH caused the obstruction, prostate treatment can occur simultaneously.

Percutaneous suprapubic cystolithotomy suits stones larger than 2-3 centimeters. The surgeon makes a small incision above the pubic bone for direct bladder access, enabling removal of very large or hard stones. Open cystolithotomy is rarely needed today but remains appropriate for massive stones, when concurrent open prostate surgery is required, or when minimally invasive approaches fail.

Treating the underlying condition is essential. BPH may require medication, transurethral resection of the prostate (TURP), or laser prostatectomy. Urethral strictures need dilation or surgical repair. Neurogenic bladder management includes clean intermittent catheterization and medications. Symptomatic bladder diverticula may require surgical removal.

Prevention

Addressing conditions that cause incomplete bladder emptying provides the foundation for prevention. Treating prostate enlargement, managing neurogenic bladder, and correcting anatomic abnormalities all reduce recurrence risk.

Adequate fluid intake keeps urine dilute and reduces mineral concentration. Aim for urine that appears clear to light yellow. Urinate regularly without holding urine for extended periods, and take time to empty the bladder completely. Treat urinary tract infections promptly, as infection alters urine chemistry and promotes stone formation.

Dietary modifications depend on stone composition but generally include limiting sodium and moderating animal protein intake. Maintaining a healthy weight reduces risk. For patients at high risk, regular follow-up with a urologist, periodic imaging, and ongoing management of underlying conditions help prevent recurrence.

When to See a Doctor

Seek medical evaluation for difficulty urinating, an interrupted urine stream, or the sensation of incomplete bladder emptying. Blood in the urine, recurrent urinary tract infections, or persistent lower abdominal pain with urinary symptoms all warrant assessment.

Sudden inability to urinate (acute urinary retention) requires emergency care. Fever with urinary symptoms suggests infection and needs prompt treatment. Following successful stone removal, regular follow-up monitors for recurrence and ensures underlying conditions remain well controlled.