Bladder stones Dr Rob Hicks Most people have heard of kidney stones but far fewer know that stones can also develop in the bladder. The good news is that treatment is available.

In this article

What causes them? Who's affected?

What are the symptoms? How are they diagnosed?

What's the treatment?

Stones form in the bladder when waste products crystallise. In most cases, these stones are made up of calcium. Stones are usually between 0.2cm and 2cm, but may be smaller or much larger.

Anything that causes urine to stagnate in the bladder creates the potential for stones to form because waste products won't be removed as they normally would. This may occur because the bladder isn't emptying completely, for example, or because of prostate gland enlargement.

A change in urine acidity, due to dehydration, can also cause a stone to form.

People who develop recurrent urine infections are also more likely to develop bladder stones. In any medical condition where the levels of waste products are higher - for example, when someone has gout - the likelihood of stones forming is also increased.

Men are more likely to develop bladder stones than women. The chances of stones forming increases with age. Most people are over 45 when the stones are discovered.

Risk factors for bladder stones include:

• Being male
• Increasing age
• Poor fluid intake
• Incomplete emptying of the bladder
• Recurrent urine infections
• Medical conditions, for example, gout

Bladder stones can act like a bath plug and stop urine flowing freely from the bladder, or they may behave like coarse gravel in a porcelain basin and scratch away at the lining, causing irritation and making someone more susceptible to infection.

When the stones are small they may pass out of the body in the urine and cause no symptoms at all.

If the stone is too large and has difficulty being passed it may cause a variety of symptoms:

• Blood in the urine
• Pain when passing urine
• Difficulty passing urine
• An urgent or frequent need to pass urine

A stone that causes irritation may also cause urge incontinence, also known as irritable bladder. One that blocks the exit of urine from the bladder causes the painful condition of urine retention.

Many tests can be used to identify what's causing someone's symptoms and whether a stone is present within the bladder. These include urine tests, blood tests, x-rays and ultrasound scans.

A special type of test called intravenous urography is often used and provides a picture of the kidneys, ureters and bladder. This allows any stones and their location to be identified.

Sometimes cystoscopy is performed to examine the inside of the bladder. During this process a fibre-optic camera, called a cystoscope, is inserted into the bladder via the urethra. Any bladder stones can usually be broken up during this procedure, and then washed out.

Stones can also be broken up into pieces small enough to allow them to pass out in the urine using a special type of ultrasound called lithotripsy. If the stones are too large to be removed by these methods, surgical removal becomes necessary.

Since bladder stones can often recur, it's important to reduce the chances of this happening. This means drinking plenty of fluid every day, and ensuring that any underlying medical conditions, such as gout, are treated appropriately.

This article was last medically reviewed by Dr Rob Hicks in November 2007