What Are Bladder Stones (Calculi)?
How These Hardened Clumps of Minerals Are Diagnosed and Treated
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Medically reviewed by Matthew Wosnitzer, MD
Bladder stones—also known as bladder calculi, vesical calculi, or cystoliths—are hardened mineral deposits that form when your urine becomes concentrated, often because the bladder doesn't fully empty.
Bladder stones do not always cause symptoms when they are passed, but larger ones can cause often extreme lower abdominal and back pain, painful urination, and blood in the urine.
Treatment isn't always needed, but some cases require a laser or ultrasonic device that can break up the stone so that it is easily passed in the urine. Very large stones may require open surgery. Without treatment, severe cases can lead to infection or bladder damage.
This article covers what you need to know about bladder stones, including their causes and symptoms and how they are diagnosed, treated, and prevented.
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What Causes Bladder Stones?
Bladder stones usually develop when you cannot completely empty your bladder of urine. When this happens, minerals and other compounds in urine can start to stick together and form crystals. Over time, the crystals can enlarge and harden into stones (calculi).
Common causes of bladder stones include:
Enlarged prostate: Also known as benign prostatic hyperplasia (BPH), this is a condition in which the enlargement of the prostate gland compresses the tube through which urine exits the body, called the urethra, making it harder to empty the bladder.
Bladder prolapse: Also known as cystocele, this is a condition that occurs when the bladder wall weakens and drops into the vagina. This also blocks the urethra and the flow of urine.
Neurogenic bladder: This is a condition in which you are unable to fully empty the bladder due to nerve damage, such as caused by a spinal cord injury, stroke, spina bifida, multiple sclerosis (MS), or Parkinson's disease.
Bladder diverticulum: These are pouches that develop in the wall of the bladder that can collect urine and make it harder to fully empty the bladder.
Bladder outlet obstruction (BOO): This is the blockage of urine from the bladder to the urethra. In addition to BPH, BOO can be caused by a urinary tract infection (UTI), sexually transmitted infection (STI), urethral stricture, pelvic tumor, or a pelvic or lower abdominal injury.
Chronic dehydration: This is when your intake of fluid is persistently low, causing your urine to concentrate and become supersaturated with minerals that are more likely to crystallize.
High purine diet: Purine is a substance found in food that is broken down into uric acid, one of the possible compounds that make up bladder stones. Eating high-purine foods like organ meats, beer, and shellfish can contribute to the formation of stones in some people.
Urinary catheters: The long-term use of urinary catheters can increase the risk of bladder stones if they are not properly maintained and end up causing an infection.
Bladder augmentation surgery: A section of the bowel is removed to make the bladder larger. Bladder stones are a common complication, affecting up to 50% of people who undergo the procedure.
Related: Bladder Pain
Types of Bladder Stones
Bladder stones, like kidney stones, vary by the minerals and compounds they are composed of. Some stones are harder to pass because of their mineral composition, while others are more common in certain individuals. You can have one or many stones of different sizes and shapes.
Examples include:
Uric acid stones: These are the most common bladder stones that often run in families and develop when uric acid levels are consistently high (known as hyperuricemia).
Calcium oxalate stones: These are a common type of urinary stone that forms when there are high levels of calcium, oxalate, cystine, or phosphate and too little liquid.
Struvite stones: These stones, composed of magnesium ammonium phosphate, are also called infection stones because they form when the urinary pH (a measure of acidity and alkalinity) changes in people with a UTI.
Jackstones: These are rare stones composed of calcium oxalate dihydrate that can be difficult to pass because they have radiating arms like toy jacks.
Bladder Stone Symptoms
Bladder stones don't always cause symptoms. Sometimes a person won't even know they've passed one until they see the stone in the toilet after they urinate.
When symptoms occur, they may include:
Lower abdominal and back pain, often extreme
Pain during urination (dysuria)
Frequent urination (urinary frequency}
Difficulty urinating (urinary retention)
A broken or interrupted urine stream
Ability to urinate only in certain positions
Frequent urination at night (nocturia)
Feeling like you need to urinate despite having an empty bladder (tenesmus)
Blood in the urine (hematuria)
Bladder leakage (urinary incontinence)
Certain bladder stones, such as struvite stones, are associated with UTIs. In such cases, there may also be fever with chills, nausea or vomiting, flank pain, and cloudy, foul-smelling urine,
When to Seek Emergency Care
Call 911 or have someone rush you to the nearest emergency room if you have:
Excruciating pain in the abdomen, groin, genitals, or side
High fever with shaking chills
Severe nausea or vomiting
The inability to pee
Related: Do I Have a Bladder Infection?
How Are Bladder Stones Diagnosed?
The diagnosis of bladder stones starts with a review of your symptoms, medical history, and diet. A physical exam would check for signs of bladder distention (enlargement) by gently palpating (pressing) the lower abdomen.
A digital rectal exam (DRE) may be used in a person with a penis to check for an enlarged prostate, while a pelvic exam may be used in a person with a vagina to check for bladder prolapse.
Based on the initial findings, other tests or procedures may be ordered, including:
Urinalysis: A urine test used to check for signs of infection or abnormalities in the chemical makeup of urine
Serum calcium: A blood test used to measure calcium levels in the body
Estimated glomerular filtration rate (eGFR): Used to determine how functional your kidneys are based on the amount of creatinine that is excreted in urine
24-hour urine collection: Used to determine how functional your kidneys are based on the volume and chemical composition of urine collected over 24 hours
Abdominal ultrasound: A noninvasive imaging tool that can detect bladder stones using high-frequency sound waves
Computed tomography (CT): An imaging tool that composites multiple X-rays to create three-dimensional (3D) "slices" of the bladder and urinary tract
Magnetic resonance imaging (MRI): An imaging tool that uses powerful magnetic and radio waves to create highly detailed images of the bladder and adjacent structures
Cystoscopy: A minimally invasive procedure that involves the insertion of a narrow scope (called a cystoscope) into the urethra to view inside your bladder
How Do You Get Rid of Bladder Stones?
Many smaller bladder stones will pass on their own without medical intervention. If your healthcare provider advises you that this is the case, you can make the passing of a stone easier by:
Drinking as much as 2 to 3 quarts (1.8 to 3.6 liters) of plain water per day to promote urination
Applying a warm compress to the lower abdomen to help relax the bladder and urethra
Taking an over-the-counter nonsteroidal anti-inflammatory drug (NSAID) like Advil (ibuprofen) or Aleve (naproxen) to help ease pain
Taking a prescription alpha-blocker—such as Flomax (tamsulosin) or Uroxatral (alfuzosin)—to help relax the bladder, urethra, prostate, and other structures of the urinary tract
How Long Does It Take to Pass a Bladder Stone?
Bladder stones usually pass faster than kidney stones because they are farther down in the urinary system. Expect smaller stones to pass on their own within two to three days and possibly longer if you are older and have an enlarged prostate or other conditions that obstruct the normal flow of urine.
Related: 4 Stages of Passing a Stone
What Happens If the Stone Won’t Pass?
If a bladder stone does pass and gets "stuck," the buildup of urine behind the blockage can exert extreme pressure on the bladder and adjacent structures. In some cases, the bladder can become permanently damaged.
Possible complications of an untreated, severe bladder stone include:
Urinary tract infection (including recurrent UTIs)
Acute kidney failure (the sudden loss of kidney function)
Chronic urination problems such as urinary frequency and overflow incontinence
Vaginal prolapse (the weakening and collapse of the vagina into the vaginal cavity)
Sepsis (a potentially life-threatening reaction to an infection that has spread to the bloodstream)
Other Treatment Options
If a bladder stone is large or does not pass on its own after several days, your urologist (specialist in conditions of the urinary tract) may recommend treatments to either break up the stone or physically remove it. Other indications for treatment include extreme pain, bleeding, the onset of a UTI, and the risk of development of kidney failure.
Treatment options include:
Electrocorporeal shock wave lithotripsy (ESWL): This noninvasive procedure delivers bursts of ultrasonic energy through the abdomen to break stones into smaller fragments. ESWL may involve light sedation or no sedation.
Transurethral lithotripsy: This involves the insertion of a cystoscope into the urethra that is specially equipped with various instruments that can either crush the stone or break it into bits with lasers or ultrasonic energy. Local or regional anesthesia may be used.
Intracorporeal lithotripsy: Also known as cystolitholapaxy, this involves the insertion of a needle-like probe through the abdominal wall. When the stone is located (by X-ray or ultrasound), it is crushed or broken up with lasers or ultrasonic energy. This outpatient procedure is usually done under regional or general anesthesia.
Open cystostomy: This surgery involves a large incision in the abdomen and bladder to remove very large stones. General anesthesia is used in this inpatient procedure. An overnight hospital stay is usually needed.
Related: How Stones Are Surgically Removed
Who’s Likely to Get Bladder Stones?
Certain people are at greater risk of bladder stones than others. Common factors contributing to bladder stones include:
Being a man over 50 (the term for sex or gender from the source is used)
A family history of bladder stones
Having an enlarged prostate
The long-term use of urinary catheters
Having abnormalities of the nervous system such as stroke, Parkinson's disease, and MS
Having uncontrolled diabetes (which can affect bladder function)
Having gout (another condition characterized by high uric acid levels)
Can I Prevent Bladder Stones?
There is no surefire way to prevent bladder stones, and some people get them despite taking the best preventive measure. Even so, if you are at risk, you can reduce the odds of getting a bladder stone by making a few lifestyle changes:
Drink plenty of water: A reasonable goal is eight 8-ounce glasses of water per day. Some people need more, so speak with a healthcare provider to determine the amount that's right for you.
Take regular bathroom breaks: If you have difficulty urinating, make a point of going to the toilet every three to four hours, even if you don't feel like going. Don't wait until your bladder is full.
Practice double voiding: Take your time when urinating. Once finished, rest a little and try again. This can better ensure your bladder is completely empty.
Cut back on purines: If you are prone to recurrent bladder stones, limit your intake of high-purine food, including beer, red meat, organ meats, anchovies, sardines, and shellfish.
Practice catheter safety: If you use a urinary catheter, clean it every day. Wash your drainage bags daily and replace them weekly.
Related: Tips for Keeping Your Urinary Tract Healthy
Summary
Bladder stones are hardened clumps of minerals that usually form when the bladder doesn't empty as it should. Causes of this include an enlarged prostate, bladder obstruction, bladder prolapse, and neurogenic bladder. Chronic dehydration, a high-purine diet, and long-term catheter use can also contribute.
Bladder stones don't always cause symptoms. Larger ones can lead to extreme lower abdominal and back pain, frequent urination, painful urination, and blood in the urine.
Bladder stones can be diagnosed with urine tests and imaging studies and may or may not require treatment. If a stone cannot be passed on its own, specialist procedures or surgeries may be used to break up the stone or remove it physically.
