Your kidneys play a key role in eliminating waste products from the human body. These waste products are then excreted as urine via the ureter into the bladder and eliminated from the bladder.

Unusually high levels of waste such as calcium oxalate or uric acid can occur for a number of reasons, which can overload the urine and over a period of time these will lead to kidney stones, which can prove to be extremely painful.

Men are more susceptible to getting kidney stones than women, plus there is a higher risk of individuals succumbing to kidney stones in hot, dry climates. Kidney stones occur more frequently during the summer months and there is higher a risk in obese patients.

What exactly is a kidney stone?

A kidney stone is a solid bit of material that forms in the kidney. It is an abnormal formation of crystals and salts which, over time, can grow in the collecting system of the organ. These substances, usually found in the urine, do not cause any issues when at lower concentrations. Kidney stones can either stay in the kidney or can travel down the urinary tract and are varied in size. A very small kidney stone might travel from the kidney down the urinary tract and pass on its own causing little pain, but larger kidney stones might get stuck along the urinary tract and block the flow of urine, causing extreme levels of pain and bleeding.

Why and how does this happen?

The urinary tract is the body’s drainage system to remove waste and extra water. Kidneys are bean-shaped organs about the size of a first located near the centre of the back just below the rib cage – one on each side of the spine.

Every day your kidneys process in the region of 180 liters of blood and plasma to produce about 1.5 to 2 litres of urine, which is made up of waste and extra water. Urine flows from the kidneys to the bladder through the ureter. Your urine naturally consists of high concentrations of waste products and salts and in certain individuals, these salts crystallise, forming kidney stones.

High levels of calcium oxalate and phosphorus in the urine are often the cause of painful kidney stones and certain foods can be the source of kidney stones in certain individuals. The exact time it takes for a kidney stone to form is not known but is estimated to develop over a couple of months and in certain instances, even years.

Although kidney stones are seldom a sign of kidney disease, the list below will indicate why you might be susceptible:

  • If you have a family history of kidney stones: children with kidney stones, however, are believed to be more at risk if kidney stones are hereditary.
  • If you suffer from recurring urinary tract infections.
  • If you have digestive problems.
  • Blockage of the urinary tract.
  • For those individuals that do not drink sufficient fluids, especially during the hot summer months or individuals that live in hot climates and do not hydrate sufficiently have a leaning towards getting kidney stones.
  • Certain medicines can cause kidney stones.

Between 10 and 15% of the general population develop kidney stones at some stage of their lives and while anyone can get kidney stones, the risk factors listed here can increase your chances.

There are several different kinds of kidney stones. Kidney stones are differentiated by various factors including diet, the ability to metabolise certain elements from food, or even changes in the function of the kidneys or the bowel.

The most common type of kidney stones are calcium-based. Calcium is a normal part of a healthy diet, but the excess not used by the bones and muscles will automatically be sent to the kidneys, and while in most individuals the kidneys flush out the excess in urine, people who have calcium stones store the calcium in the kidneys.

Calcium-based stones are the most common type – these consist of either calcium oxalate or calcium phosphate.

  • A uric acid stone will form when there is too much uric acid in the urine – about 7% of kidney stones are uric acid-based, which is a by-product of the breaking down of purine rich foods such as alcohol, meat, fish and shellfish. Individuals suffering from gout have a tendency towards getting this type of stones.
  • A further 7% of individuals suffer from struvite stones which can occur after a kidney infection or certain bacterial infections in the urine.
  • Cystine stones is a condition genetically passed down from parent to child which is caused by cystine leaking through the kidneys into the urine.

How do you know that you have kidney stones?

Individuals who suffer from kidney stones or those with a family history can be screened for risk factors where salt levels in urine and blood will be established. It is quite possible to detect stones prior to the patient experiencing painful symptoms – a simple urine test can be done to detect any tiny crystals that form in the urine. Stones are also detected on CT or sonar scans. Small stones are easily dissolved by alkalising the urine before they make their appearance.

How to prevent kidney stones:

You simply have to drink more liquids, especially during hot weather. For those that are not diligent water drinkers, it does not have to be plain water every time – new research has indicated that sparkling water protects against stone formation – more so when compared to still water. Citrus juices including lemonade are also a great way to hydrate and are good balancing options to water and will assist in increasing urinary citrate levels.

Cut the coffee – caffeine is bad for you and studies point to caffeine as being a culprit in increasing the risk of stones coming back and increasing the excretion of calcium. There is no time quite like the present to hold back on your salt intake. Not only is it bad for your heart, but studies have shown that excessive intake of salty foods and elevated salt intake causes kidney stones to recur.

Treating kidney stones:

Small kidney stones that are close to the bladder are easily passed through with a combination of medication and plenty of fluids. Larger stones, on the other hand, are extremely painful and patients normally have to be admitted to hospital where urine tests and CT scans are performed to diagnose the patient’s condition. Once the size of the stone has been determined, treatment will be carried out accordingly.

Endoscopic surgery will be performed if the stones are close to the kidneys or are unusually large in size. Kidney stones that are lodged in the kidney can be treated by ESWL (Extra Corporeal Shock Wave Lithotripsy) which are shock waves that are used to break up the stones.

Because almost half of all kidney stones sufferers will develop kidney stones within ten years after the first ones occurred and as many as 75% within 20 years, effective prevention cannot be stressed enough.

High levels of protein intake increases urinary calcium oxalate and uric acid excretion, so it might be a good idea to cut back on these foods. Consult your doctor before cutting back on calcium as a lack of calcium could lead to osteoporosis in later years.
Annual monitoring might also be a good way forward in the prevention of kidney stones.