What Are Bladder Stones? What Causes Bladder Stones?

Editor's Choice
Main Category: Urology / Nephrology
Article Date: 09 Apr 2010 - 0:00 PDT


Bladder stones are small mineral masses that develop in the bladder, usually when the urine becomes concentrated. Urolithiasis refers to stones in any part of the urinary tract, including the kidneys, bladder or urethra. The stones can be called calculi. Spinal cord injuries that result in urinary incontinence, an enlarged prostate, or recurring urinary tract infections are common causes of concentrated and stagnant urine. If urine remains too long in the bladder, urine chemicals start clumping together, forming crystals which grow and eventually develop into bladder stones.

Bladder stones used to be much more common in the UK, USA and other developed countries, when people's diets lacked a good balance of carbohydrates and proteins. Today, however, most patients in industrialized nations with bladder stones have an underlying bladder problem.

Sometimes, patients with bladder stones first know about it after tests for other problems reveal them - they may exist without any symptoms. Signs and symptoms of bladder stones may include abdominal pain, pain when urinating, or blood in urine.

A tiny bladder stone may pass out of the body on its own. However, larger ones require medical intervention to get them out. Untreated bladder stones can eventually result in infections and complications.

In medical English:

• A calculus is a stone within the body.
• The plural of calculus (stone) is calculi (stones)
• The Latin word calculus means "pebble"
• A urinary calculus is a stone in the urinary tract, such as the kidney, bladder or urethra (urine leaves the bladder to outside the body through a tube called the urethra)
• A bladder calculus is a bladder stone
• Bladder calculi are bladder stones
• A renal calculus is a kidney stone
• A urethral calculus is a stone in the urethra

According to Medilexicon's medical dictionary:

A bladder stone is a "urinary tract calculi in the bladder. Throughout most of the history of humans, this was the predominant form of urinary tract stone disease, mentioned in the Hippocratic oath, and giving rise to the common ancient surgical procedure, lithotomy. In much of the world, bladder stone disease has become uncommon and renal and ureteral stones (usually of different origins) have become more common. Bladder stones are now typically seen in patients with neurogenic bladders, urinary tract reconstruction, or infravesical obstruction"

What are the signs and symptoms of bladder stones?

A symptom is something the patient senses and describes, while a sign is something other people, such as the doctor notice. For example, drowsiness may be a symptom while dilated pupils may be a sign.

Some patients never know they had a bladder stone, which was small and eventually passed out during urination. Others with no symptoms find out after undergoing tests for some other condition. The majority of people with bladder stones do have symptoms though, which may include:

• Lower abdominal pain
• Back, buttocks or hip pain, which worsens with physical activity
• Blood in urine, or the urine may be abnormally dark
• Getting up during the night from sleep to urinate
• Intermittent urination (urination stops and starts)
• Males may experience penile and scrotal pain or discomfort
• More frequent urination
• Pain when urinating
• Some patients may find it hard to start urinating (have to wait for the flow to come)
• Urinary incontinence (unintentional leaking)

Bladder stones may be:

• So small that they come out during urination
• So large that they fill the entire bladder
• Soft
• Hard
• Smooth
• Jagged
• Spiked
• A single stone or many of them

What are the risk factors for bladder stones?

A risk factor is something which increases the likelihood of developing a condition or disease. For example, obesity significantly raises the risk of developing diabetes type 2. Therefore, obesity is a risk factor for diabetes type 2.

• Being a child in a developing nation - bladder stones are common in children in developing nations. Mainly because of dehydration and a diet that lacks protein.
  
  
• Being an elderly male in developed nations - bladder stones occur much more frequently in elderly males, compared to other humans.
  
  
• Age - people in developed nations aged over 50 years have a higher risk than younger people..
  
  
• Bladder outlet obstruction - this term refers to any condition that undermines the flow of urine from the bladder to the urethra, such as an enlarged prostate, cystocele, bladder diverticula, certain medications and narrowing of the urethra.
  
  
• Nerves that control bladder function - any condition that damages the nerves that control bladder function make the likelihood of bladder stones greater, such as a spinal cord injury, Parkinson's disease, diabetes, herniated disk, and stroke. Patients who have a neurological problem as well as some kind of bladder outlet obstruction, such as an enlarged prostate have an even greater chance of developing bladder stones.
  
  
• Recurrent bladder infections - chronic (recurrent, long-term) bladder infections cause inflammation, which may result in the development of bladder stones.
  
  
• Urinary catheters - these are slender tubes which are inserted through the urethra to the bladder to help drain urine. Urinary catheter use, especially long-term use, can increase the risk of developing bladder stones.
  
  
• Kidney stones - very small kidney stones can travel down the tubes that connect the kidneys to the bladder (ureters) and enter the bladder, where they may eventually grow into bladder stones.
  
  
• Other factors - bladder stones are more likely if a person's diet is high in fat, sugar or salt. A vitamin A and/or vitamin B deficiency may also increase the risk. These other factors are more likely to affect people in developing nations.

What are the causes of bladder stones?

By far the most common cause of bladder stones is the bladder's inability to empty itself completely.

Urine, which is produced in the kidneys, consists of water and waste products which have been removed from blood.

Urea, one of the waste products, is made of carbon and nitrogen - (NH₂)₂CO. Stagnant urine - urine that remains in the bladder because it could not empty itself fully - leads to the clumping together of the chemicals inside urea, eventually resulting in the formation of crystals.

Diagnosing bladder stones

A GP (general practitioner, primary care physician), often the first health care professional the sufferer will go to, will interview the patient and carry out a physical exam. The doctor will feel the lower abdomen to determine whether there is any bladder distention (swelling). If the individual is male a rectal exam may be done, to check the size of the prostate.

If the GP suspects there may be bladder stones, the patient will be referred to a hospital for tests, which may include:

• Urine test (urinalysis) - a urine sample is examined for blood, bacteria and crystallization of minerals.
  
  
• Cystoscopy - a cystoscope, a slender tube with a tiny camera at the end is inserted through the urethra and into the bladder. Water flows through the cystoscope into the bladder, filling it up. This stretches the bladder wall so that the doctor can see the inside of it more clearly. With a cystoscope the doctor can determine whether there are any bladder stones, how many there are, what they are like, and where exactly they all are.
  
  
• Spiral CT (computerized tomography) scan - the CT scanner uses digital geometry processing to generate a 3-dimensional (3-D) image of the inside of an object. The 3-D image is made after many 2-dimensional (2-D) X-ray images are taken around a single axis of rotation - in other words, many pictures of the same area are taken from many angles and then placed together to produce a 3-D image. It is a painless procedure. A spiral CT scans more rapidly and with greater definition - even tiny stones can be detected. This is considered the most sensitive test for detecting all types of bladder stones.
  
  
• Ultrasound scan - this device uses ultrasound waves which bounce off tissues; the echoes are converted into a sonogram (an image) which the doctor can see on a monitor. The doctor can get an inside view of soft tissues and body cavities; which in this case would be the bladder and inside the bladder.
  
  
• X-ray - may be used to determine whether there are stones anywhere in the urinary system, including the kidneys, ureters and bladder. X-rays may not detect all types of stones.
  
  
• Intravenous pyelogram (intravenous urogram) - a dye is injected into a vein in the arm. The dye flows into the kidneys, ureters and bladder, which are revealed in X-ray images. Several X-rays are taken, at specific points in time.

What are the treatment options for bladder stones?

Bladder stones should not remain in the bladder. Small ones may usually be flushed out by drinking more water - at least 6 to 8 glasses (1.2 liters) of water a day. Patients should be guided by what their doctor tells them.

If the bladder stone is too large to be flushed out on its own, the doctor may need to remove it.

• Cystolitholapaxy - crushing the stones followed by irrigation to remove fragments. A cystoscope is inserted through the urethra and into the bladder. Ultrasound waves or lasers are transmitted from the cystoscope and aimed at the stones, breaking them up. They are then flushed out.
  
  The patient will have either a local or general anesthetic for the procedure. Complications are rare, but if they do occur may include urinary tract infections, a bladder tear, and bleeding. Patients are usually administered antibiotics to reduce infection risk.
  
  Approximately one month after the cystolitholapaxy there is a follow-up meeting with the doctor to check that no fragments remained behind in the bladder.
  
  
• Surgery - if the bladder stones are too hard to crush, or too large, open surgery may be needed. The surgeon makes an incision just above the pubic hair, and another incision in the bladder and directly removes the stones. If there is an underlying condition linked to bladder stones, such as an enlarged prostate, this may be corrected too. The patient may need to use a urinary catheter until the bladder heals.

What are the possible complications of bladder stones?

Untreated bladder stones can eventually lead to:

• Chronic bladder dysfunction - the bladder does not work properly and the individual may have to urinate frequently, there may be some varying degrees of urinary incontinence as well. A stone may become stuck in the opening where the urethra joins the bladder, causing blockage and consequent urination difficulties.
  
  
• Urinary tract infections - bladder stones significantly increase the risk of recurrent urinary tract infections.
  
  
• Bladder cancer - untreated bladder stones can increase the risk of bladder cancer.

Written by Christian Nordqvist
Copyright: Medical News Today
Not to be reproduced without permission of Medical News Today

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