Violent stabbing pains in the stomach – these can be kidney stones. Once you have been affected, you must expect new ones to emerge. Simple measures can prevent the common ailment. Kidneys filter metabolic products and toxins from the blood and divert them via the produced urine. They control the salt and water balance and blood pressure, and they make vital hormones.
Kidney stones consist of substances that are actually dissolved in the urine, which crystallize. They can vary in size – the size ranges from a few millimeters – about the size of a rice grain – up to several centimeters. Mostly only one kidney is affected. A kidney stone that enters the ureter is called a ureteral stone.
It used to be thought that kidney stones always occur when dissolved salts are present in the urine in excess and crystallize. From the small crystals that form in the kidney, pebbles develop in the course of time. However, this is greatly simplified. Some people have too much of certain substances in their urine – and yet they do not form stones. Others have lower concentrations and suffer from stones. It is not known why this is so.
The so-called stone-forming substances include calcium, uric acid or oxalate. It is also problematic if there are too few stone-dissolving substances such as magnesium or citrate in the urine. This also contributes to the formation of kidney stones.
Small stones usually go unnoticed on the urine and cause no discomfort. They are often discovered only by accident – such as in an ultrasound examination. If the stones are larger, they cause pain when they enter the ureter and get stuck in it. They then block the urine drainage.
If there is a fever and chills in kidney stones, this is an emergency that needs immediate attention. It can come to a life-threatening blood poisoning.
Most kidney or urinary stones can be detected by an ultrasound scan. Sometimes a computed tomography (CT) is necessary. An X-ray examination is usually omitted today because of the radiation exposure. In addition, the doctor examines the urine and the blood. It can be diagnosed whether uric acid and calcium levels are elevated or whether an infection exists.
Treatments depend on the location and size of the stones. Smaller stones of no more than five millimeters usually come out with urine within a month. Therefore, it is often sufficient to take painkillers, to drink plenty of water and to wait. This is worth a try even with slightly larger stones (not more than ten millimeters). If necessary, medications can be given to relax the muscles. Also heat (hot water bottle, bath) has this effect. To move about, carefully hop around or climb stairs also help.
Larger stones (over ten millimeters) usually have to be smashed by sound waves or removed endoscopically. An open surgery is rarely necessary. Special medications can dissolve uric acid stones sometimes.
The risk of kidney stone can be reduced by a few simple measures:
Drink a lot and regularly: At least 2.5 liters of unsweetened liquids such as water per day. Coke and other soft drinks, on the other hand, should be avoided. They contain phosphoric acid, which probably promotes the formation of kidney stones. Coffee inhibits even the formation of stones. Citrus juices – such as a home-made, barely sweetened lemonade are good. They increase the citrate concentration in the urine. Important above all: Drink regularly.
If a lot of drinking and a change in diet are not enough, medication can also be prescribed. They specifically reduce the concentration of certain salts in the urine. They are useful if the risk for other kidney stones is great – for example, if the stones occurred for the first time in childhood or adolescence, there is a family burden or there is a previous illness.
