An A to Z on kidney stones

Helen Cowan

Here's everything you need to know about Kidney stones

When life gives you kidney stones, it might help to make lemonade. Kidney stones cause symptoms in nine per cent of the population and they can be serious, but what are the most important things you should know about the condition?

 

Agony

When kidney stones block urine flow, the kidney may stretch, causing pain akin to, or worse than, childbirth.

 

Blood

If the stone scratches the kidney or ureters (the tubes that connect the kidneys to the bladder), blood may appear in the urine.

 

Calcium 

Kidney stones are crystals made from chemicals in the urine. The “Oxford Stone Group” describe how the urine must be saturated with these chemicals for the stones to form—a bit like growing a crystal in a jar in school chemistry lessons.

They’re commonly made of something called calcium oxalate… but cutting down on calcium consumption is not advised, since it can actually increase the likelihood of kidney stones through some complex chemistry.

 

Drinking enough

Dehydration is a common cause of kidney stones.

 

Egyptians

One of the earliest recorded kidney stones was that found in an Egyptian mummy.

 

Fever

A high temperature does not usually accompany a kidney stone—if it does, it may herald an associated infection.

 

Gout

Gout can double the risk of kidney stones in men. The conditions are similar in that gout also involves the build-up of crystals, in the joints and tissues.

 

History

Kidney stone formers include Napolean I, Oliver Cromwell, William Harvey and Isaac Newton.

 

Infection

Bacteria can build up behind a kidney stone, leading to a kidney infection.

 

Jewellery

“When we break up kidney stones surgically, some of them are indeed quite beautiful—like a geode, like the rings on a tree, or something you’d hang on your wall,” says Dr Brian Matlaga. Anyone for kidney stone jewellery? 

 

Kidney damage

Kidney stone formers have a higher risk of developing chronic kidney disease, perhaps because the kidney is stretched and damaged by the build-up of urine in the ureters.

 

Lithotripsy

Is the name given to the procedure in which kidney stones are shattered by soundwaves so that the smaller pieces can then be passed more easily in the urine.

 

Medication

Is usually directed towards pain relief. For those at high risk of kidney stones, some types of water tablets can also help.

 

Nausea

Feeling sick is a common symptom of kidney stones.

 

Oxalates

These are natural substances found in foods such as nuts, spinach, chocolate, rhubarb, beetroot and strawberries. Excessive consumption can lead to kidney stones made up of calcium oxalate.

 

Parathyroid

The parathyroid glands in your neck control the amount of calcium in your blood. High levels of parathyroid hormone can cause kidney stones to form.

 

Questions

Information and support can be found at groups such as “Beat Kidney Stones” and Kidney Research UK.

 

Restlessness 

The pain of kidney stones can cause restlessness and writhing while you're trying to sleep.

 

Size

Most stones are small, being only a few millimetres in diameter, and can be passed easily in the urine. Stones larger than one centimetre are more troublesome; the largest kidney stone is reported to have weighed 1.36kg!

 

Tea strainer

Your doctor may ask you to collect the stone by urinating through a tea strainer, a stocking or a coffee filter paper. Study of the stone will help inform treatment decisions.

 

Undetected

Many stones cause no symptoms at all, and are instead a “chance” finding on a CT scan. They may stay in the kidney or pass out painlessly in the urine.

 

Vitamin C

Large doses of Vitamin C may increase the amount of oxalate in your urine, increasing the risk of kidney stone formation. “A lot isn’t necessarily better” when it comes to vitamin C and the kidney, writes Harvard Health

 

Weight

Being overweight can increase the risk of kidney stones developing.

 

X-ray

Can be useful in tracking the passage of a kidney stone. CT scans and ultrasound are also useful.

 

Young people

The peak age of onset for kidney stone formation is 20-30 years.

 

Zoo

Animals such as Squeegee the seal and Cloe the snow leopard were diagnosed with kidney stones; Cloe underwent lithotripsy to shatter her stones, in a world-first experiment.